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15 June 2010, Volume 31 Issue 12
Technology Application
Optimal Hydrolysis and Quantification of Anthocyanins in Black Soybeans
LI Gui-lan1,2,LING Wen-hua1,GAO Yong-qing2
2010, 31(12):  1-5.  doi:10.7506/spkx1002-6630-201012001
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This paper reports the use of single-factor and orthogonal array design methods to optimize the integrated ultrasonicassisted extraction and hydrolysis of anthocyanins in black soybeans prior to their HPLC quantification. The optimal conditions for extracting and hydrolyzing anthocyanins in black soybeans were determined to be: ultrasonic-assisted extraction for 20 minutes using 2 mol/L hydrochloric acid in a mixture of half methonol and half water (V/V), followed by hydrolysis for 40 minut esat 90 ℃. The mobile phase for HPLC quantification of anthocyanins in black soybeans was a mixture of 10% formic acid aqueous solution and acetonitrile and the detection wavelength was set at 520 nm. The HPLC method exhibited a good linearity over the range from 1 to 250 μg/mL for the determination of delphinidin (Dp), cyaniding (Cy) and peonidin (Pn), with a correlation coefficient of lager than 0.9999. The contents of Dp, Cy and Pn were (31.7340 ± 1.9538), (895.3267 ± 12.9120), (26.8699 ± 0.8815) mg/100 g in black soybean seed coat, and (1.0338 ± 0.0160), (76.6534 ± 0.2322), (2.1283 ± 0.3244) mg/100 g in whole black soybean, respectively.

Optimization of Subcritical Water Extraction of Proanthocyanidins from Grape Seed by Response Surface Methodology
LI Chao1,ZHENG Yi1,WANG Wei-dong1,WANG Nai-xin1,YANG Ri-fu2
2010, 31(12):  6-10.  doi:10.7506/spkx1002-6630-201012002
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In order to develop a new technology to extract proanthocyanidins, a 2 L equipment of subcritical water extraction (SWE) suitable for industrial production was designed and used to extract proanthocyanidins from grape seeds. SWE conditions for the extraction of proanthocyanidins were optimized by response surface methodology based on Box-Behnken experimental design, followed by a comparison between this technique and other extraction techniques. The results indicated that the optimal SWE conditions were determined as follows: extraction temperature 151 ℃ and extraction pressure 12 MPa for an extraction duration of 21 min; under such condtions, the extraction yield of proanthocyanidins was 3.88%. SWE required shorter length of extraction time and yielded a higher efficiency when compared with conventional Soxhlet extraction and ethanol reflux extraction. The designed 2 L equipment of SWE was highly automatic and convenient to operate.

Extraction Optimization of Antibacterial Substances from White Pepper Powder
CHEN Wen-xue1,2,HU Yue-ying1,ZHANG Wei-min1,GE Chang1,LI Cong-fa1,*
2010, 31(12):  11-15.  doi:10.7506/spkx1002-6630-201012003
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In the present study, ethanol was used for the solvent extraction of antibacterial substances from white pepper powder against Escherichia coli and their activity was evaluated in terms of the diameter of inhibition zone. The ethanol reflux extraction and the ultrasonic-assisted ethanol extraction of white pepper powder were carried out and compared, and the latter was the selected method due to smaller diameter of inhibition zone of the extract obtained. Single factor and quadratic rotation general combination design methods were employed to optimize the product of diameter of inhibition zone and weight percentage yield of dried ethanol extract from white pepper powder varying with ultrasonic-assisted ethanol extraction conditions. The results showed that the optimal conditions for the extraction of antibacterial substances from white pepper powder were determined to be: ethanol concentration 81% for 720 min soaking followed by 80 min ultrasonic-assisted extraction.

Preparation and Identification of Monoclonal Antibody against Ciprofloxacin
YANG Xian-le1,HUANG Xuan-yun1,HU Kun1,FANG Wei1,WANG Lian2,JIANG You-sheng1,*
2010, 31(12):  16-20.  doi:10.7506/spkx1002-6630-201012004
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The ciprofloxacin-bovine serum albumin conjugate (CIP-BSA) was prepared by a modified carbodiimide method, and identified by ultraviolet spectrometry and polyacrylamide gel electrophoresis (SDS-PAGE). Then CIP-BSA was used as immunogen to immunize BALB/c mice, inducing the secretion of antibodies against hapten CIP. The monoclonal antibodies (Mabs) against CIP were obtained by hybridoma technology and their titer, affinity and specificity were identified. The results showed that CIP-BSA coupling ratio was 30:1, and two Mabs secreted by cell lines JY-1 or JY-2 belonging to IgG1a were screened by the indirect ELISA method. The titers of purified JY-1 and JY-2 Mabs were 5.12 × 106 and 2.56 × 106, respectively; both the Mabs showed high affinity to CIP with affinity coefficients of 2.88 × 109 and 2.46 × 109 L/mol respectively. A competitive inhibition curve of the JY-1 Mab was developed, and the IC50 was 9.83 ng/mL. The JY-1 Mab exhibited high cross-reactivity (95%) with enrofloxacin. These results suggested that the JY-1 Mab was useful for determination of CIP residues in aqua-products.

Supercritical Carbon Dioxide Impregnation of Vitamin D3 into Chitosan Particles
HONG Liu,SHEN Pei-qiong,SUN Li-jun,ZHAO Ya-ping*
2010, 31(12):  21-24.  doi:10.7506/spkx1002-6630-201012005
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The impregnation of vitamin D3 into chitosan particles using supercritical CO2 fluid was investigated with respect to the effects of pressure, temperature and length of impregnation time evaluated by UV-vis spectroscopy. The results showed that with increasing pressure, VD3 impregnation amount initially increased and then decreased; as temperature increased, an identical change pattern in VD3 impregnation amount was observed. VD3 impregnation amount reached its maximum value under the conditions of 20 MPa and 35 ℃. Increasing length of impregnation time from 1 to 3 h resulted in a higher VD3 impregnation amount when pressure and temperature kept unchangeable.

Bioassay-guided Extraction of Antimicrobial Substances from Clove
ZHANG Yan-nan1,CHEN Yan1,PENG Xin-li1,WANG Da-wei2,*
2010, 31(12 ):  25-27.  doi:10.7506/spkx1002-6630-201012006
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Solvent extraction was used to extract antimicrobial substances from clove against a Penicillium strain preserved in our laboratory, and their activity was evaluated by paper disc method. The clove extracts obtained using water, 60% ethanol, nhexane or acetone were tested for their diameters of inhibition zone and ethanol was the selected solvent due to the smallest diameter of inhibition zone. This was followed by the optimization of diameter of inhibition zone of ethanol extract from clove using single factor and orthogonal array design methods. The results showed that the optimal conditions for improved extraction of antimicrobial substances from clove were as follows: ethanol concentration 60%, solid-to-liquid ratio 1 g:12 mL and extraction temperature 60 ℃ for a reflux extraction duration of 2 h.

Production Optimization of β-Sitosterol Microcapsules and Their Protective Effect against Lipid Oxidation
GAO Li,FU Hong-fei,CUI Fang,LU Qi,PAN Si-yi*
2010, 31(12):  28-32.  doi:10.7506/spkx1002-6630-201012007
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β-Sitosterol has numerous biological functions such as antioxidation and so on. β-Cyclodextrin (β-CD) was taken as wall materia1 to prepare β-sitosterol microcapsules with better antioxidant effect. The preparation of β -sitosterol microcapsules was optimized using single factor and orthogonal array design methods, followed by a comparison of protective effect against lard oxidation with unmicroencapsulated β -sitosterol and vitamin E. The results showed that the optimal conditions for β-sitosterol microencapsulation were determined to be: water amount 60 mL, temperature 50 ℃, length of stirring time 50 min and ratio of 0.05 g/mL ethyl acetate solution of β -sitosterol to β -CD 1:10 (mL/g). Under these conditions, the embedding ratio of β-sitosterol was 87.98%. β-Sitosterol microcapsules could significantly protect lard from oxidation in a dosedependent way and was superior to unmicroencapsulated β-sitosterol and vitamin E.

Technology Application
Oxidation Stability of Alpha-Linolenic Acid-rich Milk from Dairy Cows Subjected to Duodenal Infusion of Perilla Oil
LIU Qing-sheng1,2,WANG Jia-qi1,*,BU Deng-pan1,Khas-Erdene1,YANG-Guang1,SUN-Peng1,LIU Kai-lang1,ZHAO Guo-qi2
2010, 31(12):  33-38.  doi:10.7506/spkx1002-6630-201012008
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Milk samples from dairy cows subjected to duodenal infusion of perilla oil rich in free alpha-linolenic acid were stored in darkness at either 4 or 20 ℃ for different periods of time (0, 72 or 120 h) in order to investigate the effect of storage conditions on the oxidation stability of the milk. It was observed that as the amount of perilla oil infused increased, the oxidation stability of freshly harvested milk samples showed a downward tendency; for milk samples stored for 72 h at 4 ℃, the oxidation stability remarkably decreased; and there was no obvious difference in the oxidation stability of milk samples stored for up to 120 h at the same temperature. Under the storage conditions of 20 ℃ and 72 h, the oxidation stability of milk samples tended to be lower with increasing amount of perilla oil infused. When the length of storage was prolonged up to 120 h at the same temperature, a significant decrease in the oxidation stability of milk samples was observed. Our findings suggested that different amounts of perilla oil infused caused different fatty acid composition in milk, resulting in significant differences in its oxidation stability under the same storage conditions.

Optimization of Ultrasonic-assisted Extraction of Carotenoids from Sweet Orange Peel
MA Shao-jun,FU Hong-fei,XIE Bi-jun,XU Xiao-yun,LI Xiu-juan,PAN Si-yi*
2010, 31(12):  39-44.  doi:10.7506/spkx1002-6630-201012009
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In order to improve the utilization and value of sweet orange (Citrus sinensis cv. Tarocco) peel, a byproduct of the juice industry, the ultrasonic technique was used to extract carotenoids from the material. A series of experiments based on single factor and orthogonal array designs was carried out to study the effects of extraction times and temperature and length of extraction time on carotenoid yield. Lyophilization was the optimal method for drying the material and the optimal technological conditions for carotenoid extraction from sweet orange peel were determined as follows: material particle size 100-120 mesh, ratio of material to liquid 1:50 (g/mL) and ultrasonic power 270 W for 4- or 5-time extraction at 30-50 ℃ for 7-10 min each time. Under such conditions, carotenoid yield was estimated to range from 0.130 - 0.150 mg/g, and the maximum value was estimated to be 0.156 mg/g and was observed to be 0.152 mg/g. The HPLC analysis revealed that carotenoids extracts obtained by ultrasonic-assisted extraction and by stirring-assisted extraction had basically identical chemical composition.

A Strategy for the Preparation of Monoclonal Antibody against Vardenafil
GUO Jie-biao,XU Yang*
2010, 31(12):  45-48.  doi:10.7506/spkx1002-6630-201012010
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To generate a monoclonal antiboby specific to both vardenafil and its analogues, glutaraldehyde was used as conjugating reagent to link vardenafil to immunogen, leaving the common structure of vardenafil and its analogues exposed on the surface of conjugates as major epitode. Through optimization, immunogen with a molar ratio of 6.8:1 could induce a high titer specific antibody in sera of mice. By using hybridomas technique, 4 monoclonal antibodies with the ability to recognize vardenafil and its analogue piperidenafil were obtained.

Using Response Surface Analysis for Optimizing Ultrasonic-assisted Extraction of Saponins from the Roots of Platycodon grandiflorum
XU Li-ping,LI Xiao-mei,WANG Xin
2010, 31(12):  49-52.  doi:10.7506/spkx1002-6630-201012011
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Saponins in the roots of Platycodon grandiflorum were extracted with distilled water under the assistance of ultrasonic, and the extraction process was optimized by using response surface analysis based on Box-Behnken design to examine the effects of extraction conditions including material-to-liquid ratio, length of ultrasonic treatment time and extraction temperature on saponin yield, which were reflected by a quadratic regression model. The results showed that the optimal values of the above extraction conditions were as follows: material-to-liquid ratio 1: 9.75 (g/mL), length of ultrasonic treatment time 31 min and extraction temperature 35 ℃. Under these conditions, the saponin yield was 4.64%, higher than before the optimization.

Ultrasonic-assisted Extraction and Antioxidant Evaluation of Polyphenols from Peanut Seed Testa
ZHAO Ping1,2,LIN Ying-ji2,JIN Zheng-yu1,WANG Ya2,WANG Li2,QI Wen-jing2
2010, 31(12):  53-57.  doi:10.7506/spkx1002-6630-201012012
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In this paper, it reports the use of one-factor-at-a-time and orthogonal array design methods to optimize the ultrasonicassisted extraction of polyphenols from peanut seed testa (PTP), followed by the evaluation of their antioxidant effects by reducing power assay and Rancimat assay. The results indicated that the optimum conditions for the extraction of polyphenols were determined to be: material-to-liquid ratio 1:16 (g/mL), ethanol concentration 80%, ultrasonic power 240 W and length of extraction time 10 min. The above conditions exhibited different effects on polyphenol extraction in the following order: material-to-liquid ratio > ethanol concentration > length of extraction time > ultrasonic power. Under the same concentrations, the reducing power of the purified PTP was superior to that of VC. The concentration of the purified PTP providing the best protective effect against lipid oxidation in lard was found to be 150 mg/L. Addition of the purified PTP at 150 mg/L resulted in longer induction time of oxidation of lard than that of VC or gallic acid, but was inferior to that of BHT. In conclusion, PTP appears to provide a promising natural antioxidant.

Use of Response Surface Methodology to Optimize Hemoglobin Microencapsulation
YU Chang-qing,WANG Chang-rui,YAO Mei-na
2010, 31(12):  58-61.  doi:10.7506/spkx1002-6630-201012013
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Central composite design followed by multiple regression analysis and response surface analysis was employed to optimize hemoglobin microencapsulation. The results showed that the optimum conditions for hemoglobin microencapsulation were as follows: wall material-to-core material ratio 19.5:1 (g/mL), wall material concentration 9.8 g/100 mL and length of prefreezing time 13.0 h. Under such conditions, the embedding ratio of hemoglobin was 92.2%.

Microwave-aided Extraction and Free Radical Scavenging Activity of Total Flavonoids from Mistletoe
LI Ying-lei1,CHEN Jian-hua2,CHEN Ya-zhou1
2010, 31(12):  62-66.  doi:10.7506/spkx1002-6630-201012014
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In this paper, we develop an optimized procedure for the microwave-aided extraction of total flavonoids from mistletoe and test their in vitro scavenging activity against DPPH and hydroxyl (generated in Fenton system) free radicals. The optimization of the procedure for total flavonoids extraction was carried out using single factor and orthogonal array methods, in which the effects of extraction conditions on total flavonoids yield from mistletoe were evaluated. The results showed that the optimum conditions for total flavonoids extraction were as follows: ethanol concentration 70%, microwave power 500 W, solidto- liquid ratio 1:40 (g/mL) and extraction temperature 70 ℃. Under these conditions, the extraction yield of total flavonoids from mistletoe was up to 1.88%. The IC50 values of the extracted total flavonoids for DPPH and hydroxyl free radicals were 0.036 mg/mL and 0.572 mg/mL, respectively. Based on these results, it can be concluded that mistletoe total flavonoids is a promising free radical scavenger and that the developed extraction procedure is simple and convenient and consequently, is most suitable for large-quantity industrial production of mistletoe total flavonoids.

Extraction of Total Flavonoids from the Peel of Ponkan Mandarin (Citrus reticulata Blanco) by Optimized Cellulase Hydrolysis
OUYANG Hui,YU Ji,ZHANG Yong-kang
2010, 31(12):  67-70.  doi:10.7506/spkx1002-6630-201012015
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The purpose of the present study was to investigate the use of response surface methodology based on Box-Benhnken experimental design to optimize the cellulase hydrolysis of Ponkan mandarin peel for the extraction of total flavonoids. The optimum hydrolysis conditions for the extraction of total flavonoids were determined to be: enzyme concentration 120 U/mL, hydrolysis temperature 52 ℃, length of hydrolysis time 140 min and pH 4.35. Under such conditions, the extraction yield of total flavonoids reached up to 1.85%.

Optimization of Some Process Conditions for the Alkline Extraction of Phenolic Acids from Bamboo Residues by Response Surface Methodology
HU Zheng-rong1,2,LIU Yu-huan1,2,3, RUAN Roger1,2,*,PENG Hong1,2,ZHANG Jin-sheng1,2
2010, 31(12):  71-75.  doi:10.7506/spkx1002-6630-201012016
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This study aimed at developing an optimal process for the alkine extraction of phenolic acids from bamboo residues. To investigate the effects of hydrolysis temperature, length of hydrolysis time and NaOH concentration as well as their pairwise interactions on the yield of phenolic acids from bamboo residues, the use of Box-Behnken design combined with response surface methodology was evaluated. The results showed that the optimum values of the above process conditions were determined to be: NaOH concentration 1.65% for a hydrolysis duration of 190 min at 75.5 ℃. Under such conditions, the yield of ferulic acid belonging to the group of phenolic acids was determined by means of UV spectroscopy (at 320 nm) to be 29.2503mg/g, very consistent with the theoretical prediction of 29.9566 mg/g. Added antioxidants to the alkine hydrolysis system was able to reduce loss of ferulic acid caused by oxidation. In conclusion, the developed process is applicable.

Using AB-8 Macroporous Resin for the Separation and Purification of Total Flavonoids from Folium Ilicis Cornutae
LIU Zhi-xiang,ZENG Chao-zhen,ZHANG Yue
2010, 31(12):  76-79.  doi:10.7506/spkx1002-6630-201012017
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The application of AB-8 macroporous resin for the separation and purification of crude total flavonoids extract from Folium Ilicis Cornutae was evaluated in the present study. The static adsorption-desorption process of Folium Ilicis Cornutae total flavonoids on this resin was optimized using single factor and orthogonal array design methods. The results showed that a good separation and purification of crude total flavonoids extract from Folium Ilicis Cornutae was achieved using AB-8 macroporous resin. The optimum conditions for the separation and purification of crude total flavonoids extract from Folium Ilicis Cornutae were found to be: 4 h adsorption at pH 4.5 of the sample solution, followed by 2.25 h desorption using 90% ethanol as desorption solvent added at 25-fold volume of resin weight. Under these optimum conditions, the recovery of Folium Ilicis Cornutae total flavonoids reached up to 90.8% and the purity of the final product obtained was 33.4%.

Extraction Optimization of Total Flavonoids from the Flowers of Dendranthema morifolium (Ramat) Tzvel. cv. Chuju
WANG Song,BAO Fang-yin,ZHENG Yu-hua
2010, 31(12 ):  80-82.  doi:10.7506/spkx1002-6630-201012018
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Pure water and aqueous solutions of ethanol at different concentrations were used to extract total flavonoids from the flowers of Dendranthema morifolium (Ramat) Tzvel. cv. Chuju at 60 ℃, respectively, and ethanol aqueous solution was the selected solvent for total flavonoids extraction based on experimental results. This was followed by the optimization of the process for total flavonoids extraction using orthogonal array design. The results indicated that the optimum extraction conditions were determined as follows: ethanol concentration 80%, extraction temperature 70 ℃ and solid-to-liquid ratio 1:100. Among these conditions, solid-to-liquid ratio exhibited the most significant effect on total flavonoids extraction.

Extraction Optimization of Total Flavonoids from the Flowers of Dendranthema morifolium (Ramat) Tzvel. cv. Chuju
ZHANG Zhi-qing,SHUAI Jin,ZHOU Li-ming,LU Xiao-fei,YAO Yan-yan
2010, 31(12):  83-88.  doi:10.7506/spkx1002-6630-201012019
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Pure water and aqueous solutions of ethanol at different concentrations were used to extract total flavonoids from the flowers of Dendranthema morifolium (Ramat) Tzvel. cv. Chuju at 60 ℃, respectively, and ethanol aqueous solution was the selected solvent for total flavonoids extraction based on experimental results. This was followed by the optimization of the process for total flavonoids extraction using orthogonal array design. The results indicated that the optimum extraction conditions were determined as follows: ethanol concentration 80%, extraction temperature 70 ℃ and solid-to-liquid ratio 1:100. Among these conditions, solid-to-liquid ratio exhibited the most significant effect on total flavonoids extraction.

Optimization of Supercritical CO2 Extraction of Kiwi Fruit Seed Oil
LI Jia-xing1,2,LI Min-li2,CHEN Jian-fu2,LIU Fei2,CHEN Shuang-ping3,WANG Xiao-yong3
2010, 31(12):  89-92.  doi:10.7506/spkx1002-6630-201012020
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The supercritical CO2 extraction of kiwi fruit seed oil was carried out in two modes, namely constant pressure and two-stage pressure reducing separation, and the latter mode was selected for the studies carried out subsequently due to better physico-chemical properties and sensory attributes of kiwi fruit seed oil. Some conditions for the supercritical CO2 extraction of kiwi fruit seed oil in the latter mode were optimized using single factor and orthogonal array design methods. The results showed that the optimum values of pressure and temperature were found to be 9 MPa and 42 ℃ in separation pot Ⅰand 6 MPa and 20-30 ℃ in separation pot Ⅱ, respectively. The water content and acid value of the product extracted under these conditions were both very low and could meet the requirements of relevant industrial standards without refining.

Separation of Formononetin from Millettia nitita var. hirsutissima Using High-Speed Counter-current Chromatography
RUAN Zheng1,2,WU Chang-qiang1,2,YIN Yu-long1,2,3,DENG Ze-yuan1,2,*
2010, 31(12):  93-96.  doi:10.7506/spkx1002-6630-201012021
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Purpose: To develop the experimental system for the separation of formononetin from Millettia nitita var. hirsutissima by high-speed counter-cunent chromatography (HSCCC). Methods: The optimum solvent composition for HSCCC separation was determined based on partition coefficients and phase separation times for various fractions of the Millettia nitita var. hirsutissima. The purity of the formononetin fraction from HSCCC separation was measured by HPLC. Results: A mixture of n-hexane, ethylacetate, methanol and water (4:5:4:5, V/V) was the selected solvent system, the upper phase and the lower phase separated from which provided mobile phase and stationary phase, respectively. The HSCCC separation of formononetin was carried out under the following conditions: flow rate 2.0 mL/min, rotation speed 800 r/min and 26 ℃. The yield of formononetin purified from the ether extract from Millettia nitita var. hirsutissima was 16.1%, with 96.3% purity. Conclusion: The developed solvent system can provide a reliable separation of formononetin. The HSCCC method is applicable for the rapid and efficient separation of formononetin.

Ceramic Membrane Ultrafiltration for the Concentration of Pectin Solution
WU Chao-liang,JIN Jiang*
2010, 31(12):  97-100.  doi:10.7506/spkx1002-6630-201012022
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The use of a ceramic membrane of 0.1 μm in pore size to concentrate pectin solution was evaluated. The effects of operation temperature, trans-membrane pressure and pectin concentration on permeation flux were investigated. The results showed that permeation flux tended to remain stable after 1 h of running. A stable permeation flux of 145 L/(h·m2) was obtained under the conditions of trans-membrane pressure 0.08 MPa, pectin concentration 0.5% and operation temperature 55 ℃.

Purification of Valtrate from Valeriana officinalis L.var. latifolia Miq by Optimized Macroporous Resin Adsorption
LI Ji-lie1,HUANG Ling1,CUI Pei-wu2,HAO Ju-xi1,WANG Wei1
2010, 31(12):  101-105.  doi:10.7506/spkx1002-6630-201012023
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The purpose of the present study was to evaluate the use of macroporous resin adsorption for purifying crude valtrate extract from Valeriana officinalis L.var. latifolia Miq. Five macroporous resins were tested for their static adsorption/desorption performance towards Valeriana officinalis L.var. latifolia Miq valtrate, and D101 resin was the selected adsorbent. The optimal values of sample concentration and sample loading amount were determined to be 10.0 mg/mL and 20 mL/13 g resin, respectively, and an amount of desorption solvent (aqueous methanol solution) of 4 BV was found enough to recover adsorbed valtrate. A quadratic general rotary unitized design involving 20 experiments of 3 variables at 5 levels combined with multiple regression analysis leading to a quadratic regression model was employed to deal with the effects of sample flow rate, desorption flow rate and methanol concentration in aqueous solution on valtrate recovery. The optimal values of the process conditions were found to be: sample flow rate 2.5 BV/h, desorption flow rate 1.7 BV/h and methanol concentration in aqueous solution 75%. Under the optimized conditions, the theoretical and experimental values of valtrate recovery from crude extract from Valeriana officinalis L.var. latifolia Miq were 72.40% and (72.12± 0.1)%, respectively.

Formulation Optimization of a Liquid Nutritional Supplement for the Production of Nutrition-fortified Rice and Its Adsorption Characteristics onto Rice
ZHANG Yan-rong1,ZHANG Yan-ling2,WANG Da-wei1,*
2010, 31(12 ):  106-109.  doi:10.7506/spkx1002-6630-201012024
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A liquid nutritional supplement was developed and used to spray rice, and nutritional-fortified rice was obtained after tempering and drying. The orthogonal array optimization demonstrated that the optimum formula for the nutritional supplement was composed of a mixture of sodium alginate 0.3 g, arabic gum 0.1 g, gelatin 0.15 g and sucrose ester 0.1 g dissolved in 30 g of water for spraying 100 g of rice. The nutritional-fortified rice produced using such a nutritional supplement exhibited a rich lustrous surface, with 59.63% nutrient adsorption ratio.

Microwave Extraction and Free Radical Scavenging Activity of Ablmoschus manihot (L.) Medic Seed Oil
QIU Yan
2010, 31(12):  110-113.  doi:10.7506/spkx1002-6630-201012025
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Ablmoschus manihot (L.) Medic seed oil was extracted by microwave extraction. Through the optimization by single factor and orthogonal array design methods, the optimum conditions for Ablmoschus manihot (L.) Medic seed oil extraction were determined to be: extraction solvent, ethyl acetate; microwave power, 540 W; and liquid/solid ratio, 10:1 for an extraction duration of 3 min. Under these conditions, the maximum oil extraction yield was 25.2%. The abilities of Ablmoschus manihot (L.) Medic seed oil to scavenge hydroxyl and superoxide anion free radicals were both determined, and it presented strong hydroxyl free radical scavenging activity, with a median effective concentration (EC50) of 0.129 mg/mL. So, Ablmoschus manihot (L.) Medic seed oil appears to be a promising free radical scavenger.

Development of Yogurt with Eucommia Tea and Effect of Respective Additions of Eucommia Tea and Chlorogenic Acid on Yogurt Fermentation and in vitro Digestion Rate of the Product
LIU Liang1,LU Qi2,DUAN Jia-cai2,GAO Li2,ZHOU Ying2,LU Si-yi2,PAN Si-yi2,*
2010, 31(12):  114-118.  doi:10.7506/spkx1002-6630-201012026
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With the addition of eucommia tea powder, fresh milk was fermented with Lactobacillus to produce a novel functional yogurt. The effects of eucommia tea powder amount, white sugar amount, inoculum size and compound stabilizer (a mixture of CMC and carrageen, 1:1, m/m) amount on the sensory attributes of yogurt were studied using orthogonal array design method. The results showed that the optimum values of these conditions were as follows: eucommia tea powder amount 0.15%, white sugar amount 6%, inoculum size 8% and compound stabilizer 0.1%, the product obtained was good in color, aroma, taste and texture. Respective additions of eucommia tea and chlorogenic acid were both able to affect yogurt fermentation. Although containing complex components, eucommia tea promoted acid production, whereas chlorogenic acid presented an inhibitory effect on acid production. Eucommia tea had no adverse effect on yogurt quality and in vitro digestion rate.

Ultrasonic-assisted Liquid Carbon Dioxide Extraction of Celery Seed Oil
XU Hua-min
2010, 31(12):  119-122.  doi:10.7506/spkx1002-6630-201012027
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Objective: To optimize the extraction of celery seed oil with liquid carbon dioxide under the assistance of ultrasonic for achieving maximum oil yield. Methods: The effects of four process conditions, i.e., extraction pressure, length of extraction time, ultrasonic power and material-to-liquid ratio on the yield of celery seed oil were investigated using single factor and orthogonal array design methods. Results: The significance sequence of the conditions influencing the yield of celery seed oil was as follows: length of extraction time > ultrasonic power > extraction pressure > material-to-liquid ratio, and their optimum values were as follows: temperature 30 min, ultrasonic power 100 W, extraction pressure 4 MPa and material-to-liquid ratio 1:7 (m/V). Under these conditions, the yield of celery seed oil reached up to 2.8%. Conclusion: Ultrasonic-assisted liquid carbon dioxide extraction provides a new and efficient separation technique for celery seed oil extraction.

Extraction and Purification of Total Polyphenols from Elaeagnus angustifolia Seeds
HU Jun-ping1,YANG Jian-hua1,2,WANG Xiao-mei1,WANG Xiao-qing1,RENA Kasimu1
2010, 31(12):  123-126.  doi:10.7506/spkx1002-6630-201012028
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Objective: To study the respective processes for the extraction and purification of total polyphenols from Elaeagnus angustifolia seeds. Methods: Mixtures of methanol and water at different volume ratios were used to extract total polyphenols from Elaeagnus angustifolia seeds, and 40% aqueous methanol solution was selected. Reflux extraction presented higher both yield and purity of total polyphenol extract when compared to ultrasonic extraction and shaking extraction. Subsequently, orthogonal array design method was used to optimize the process for the reflux extraction of total polyphenols using 40% aqueous methanol solution. In the final section of this study, the purification of the crude total polyphenol extract from Elaeagnus angustifolia seeds was investigated by macroporous resin adsorption or ionic precipitation. Results: The optimal extraction process of total polyphenols from Elaeagnus angustifolia seeds was based on the use of 30-fold volume of 40% aqueous methanol solution to extract the material three times for 1 h each time, followed by vacuum condensation. Macroporous resin adsorption was found more suitable for the purification of the crude total polyphenol extract from Elaeagnus angustifolia seeds than ionic precipitation. An optimal purification was achieved through the steps of adsorption of the target products onto AB-8 resin, washing with distilled water until no saccharides could be detected in the eluate, elution with 2-fold bed volume of 40% aqueous methanol solution, harvesting of eluate fractions, condensation and drying. The preparation of total polyphenols from Elaeagnus angustifolia seeds was performed in triplicate, and an average value of product purity of 52.17% was obtained. Conclusion: The preparation method integrating the above optimized extraction and purification processes has the benefits of good repeatability and stability..

Macroporous Resin Adsorption for the Separation of Total Flavonoids from Chrysanthemum indicum L.
YE Chun,ZHANG Jing
2010, 31(12):  127-131.  doi:10.7506/spkx1002-6630-201012029
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Totally, 12 macroporous resins were tested for their adsorption and desorption performance to total flavonoids from Chrysanthemum indicum L., and 3 of them, namely XDA-1, LSA-21 and AB-8 resins were selected for subsequent studies, which were carried out to investigate the static adsorption and desorption behaviors of the selected resins. Finally, XDA-1 resin was selected to purify crude total flavonoid extract from Chrysanthemum indicum L. due to its higher adsorption capacity (84.1mg/g) and desorption ratio (96.2%) and better static adsorption kinetics than those of LSA-21 and AB-8 resins. The optimum pH for XDA-1 resin adsorption ranged from 4 to 5 and the optimum desorption solvent 70% ethanol.

Optimization of Some Conditions for Yacon Juice Processing and Its Effect of the Growth of Bifidobacterium and Escherichia coli
LU Ming-sheng1,WANG Shu-jun1,XU Xing-quan2,FANG Yao-wei1,LIU Shu1
2010, 31(12):  132-136.  doi:10.7506/spkx1002-6630-201012030
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A process comprising the steps of selection, cleaning, cutting, blanching, breaking, cellulase hydrolysis, squeezing, pectinase hydrolysis and sterilization was designed for yacon juice processing. The optimum blanching temperature and length of blanching time were 100 ℃ and 2.5 min, respectively. According to the orthogonal array optimization, an optimum juice percentage of yacon was achieved by the hydrolysis at 50 ℃ and pH 5 for 45 min with added cellulase at 0.08%. The optimum pectinase amount for improved clarity of yacon juice was 0.14%. Yacon juice obviously promoted the growth of Bifidobacterium, resulted in 53% increase of Bifidobacterium biomass at 10% addition level, but had an inhibitory effect on the growth of Escherichia coli.

Preparation of Mogroside Ⅴ from the Fruits of Siraitia grosvenorii by Semi-Preparative HPLC
NING De-sheng1,LIANG Xiao-yan1,FANG Hong1,YAO Chong-hui2
2010, 31(12):  137-140.  doi:10.7506/spkx1002-6630-201012031
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Objective: Semi-preparative HPLC was employed to establish a fast, stable and efficient method for preparation of high purity mogroside V. Methods: The crude mogroside V extract from the fruits of Siraitia grosvenorii was decolorized by D101 macroporous resin column chromatography before semi-preparative HPLC separation. Based on the use of Eclipse XDBC18 (9.4mm× 250 mm, 5μm) held at 38 ℃, the chromatographic conditions employed were as follows: mobile phase, a mixture of acetonitrile and water at a flow rate of 4 mL/min in the gradient elution mode, detection wavelength, 210 nm; abd sample load 36 mg. Results: The purity of the product obtained was as high as 99.1%. Conclusion: The developed method, thanks to the benefits of simplicity, rapidity, good stability and obtaining of high purity products, will have a good application prospect .

Optimization of Extraction Process of Polysaccharides from Sophora alopecuraides L. seeds by Response Surface Analysis
AI Lian-zhong
2010, 31(12 ):  141-143.  doi:10.7506/spkx1002-6630-201012032
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This paper describes the optimization of extraction process of polysaccharides from Sophora alopecuraides L. seeds by response surface analysis (RSA), where the effects of extraction temperature, length of extraction time and material-to-water ratio and their interactions on polysaccharide yield were dealt with. The optimal conditions for the extraction of polysaccharides from Sophora alopecuraides L. seeds were obtained to be: e the optimization of extraction process temperature 75 ℃, length of extraction time 3 h and material-to-water ratio 1: 25, and the maximum polysaccharide yield was 70.25% under these conditions.

Solid Acid-catalyzed Hydrolysis of Burdock Roots for Fructose Preparation
WANG Lei,MA Li-hua*,QIN Wei-dong,CHEN Xue-hong,ZHANG Xu
2010, 31(12):  144-147.  doi:10.7506/spkx1002-6630-201012033
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Burdock roots containing inulin provided a raw material for the preparation of fructose derived from hydrolyzed inulin. D061 strong cation resin, a solid acid was used as catalyzer to prepare fructose. The effects of the main hydrolysis conditions, i.e., solid-to-liquid ratio, hydrolysis temperature, length of hydrolysis time and hydrolysis times on hydrolysis rate and reducing sugar content were investigated by single factor and orthogonal array design methods. The results showed that the use of D061 strong cation resin to repeatedly extract the material 3 times at 75 ℃ and 1:2 solid-to-liquid ratio for 120 min each time provided an optimal hydrolysis, and the resulting hydrolysis rate and reducing sugar content were 76.7% and 145.8 g/L, respectively.

Using Response Surface Methodology for Optimizing Pigments Extraction from the Leaves of Purple Sweet Potato
YANG Ping,NIU Chun-yan
2010, 31(12):  148-152.  doi:10.7506/spkx1002-6630-201012034
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In this paper, we develop an optimal ethanol extraction process of pigments from the leaves of purple sweet potato based on an investigation of the effects of 95% ethanol amount, length of extraction time, extraction temperature and pH on pigments extraction using single factor method and response surface methodology. The results showed that the optimal extraction process was based on the use of 12-fold volume of 95% ethanol acidified to pH 5 as extraction solvent for 24 h extraction at 50 ℃.

Analysis & Detection
Changes in Aromatic Components in Raw Pu-erh Tea during Storage
ZHANG Wen-yan1,ZHU Chun-hua1, ZHOU Hong-jie2,GONG Jia-shun1,*
2010, 31(12):  153-155.  doi:10.7506/spkx1002-6630-201012035
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Significant changes were observed in the aromatic components in raw Pu-erh tea stored for between 3 and 8 months at (25 ±1) ℃. However, Pu-erh tea samples stored for 3 and 8 months at (35 ±1) ℃ exhibited similar kind and contents of aromatic components, with significant changes when compared to pre-storage samples. Totally 15 new aromatic compounds were found in both raw Pu-erh tea samples stored for 8 months at (25 ±1) or (35 ±1) ℃, in which β-ionone epoxide, jasmine ketone, dioctyl phthalate, phenol derivatives were the predominant compounds. In conclusion, both storage temperature and period contributed greatly to changes in the aromatic components in raw Pu-erh tea and 8-month storage significantly improved the aroma of raw Pu-erh tea.

Liquid Chromatographic Determination of Flavonoids in Rosa multiflora Thunb. from Xinjiang
DILINUR Malike,MAOJUDAI Yaermaimaiti,AZIGULI Muasailimu
2010, 31(12):  156-158.  doi:10.7506/spkx1002-6630-201012036
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A simple and rapid liquid chromatographic (LC) method was developed for determining total flavonoids in Rosa multiflora Thunb from Xinjiang. A mixture of methanol, isopropanol and deionized water was used for the chromatographic separation at a flow rate of 1 mL/min. The detection wavelength was set at 360 nm. Baseline separation was achieved for rutin and quercetin within 4 min. The contents of rutin and quercetin in Rosa multiflora Thunb from Xinjiang were 17.7 μg/g and 94.7μg/g (calculated on the basis of dry weight). Mean recoveries for rutin and quercetin at the spike level of 100μg/mL were 95.6% and 97.3%, respectively, and the RSDs were both below 5%. The repeatability of the developed method was good. As a conclusion, it is applicable for rapid determination of flavonoid compounds in Rosa multiflora Thunb, like rutin and quercetin.

Purge and Trap GC-MS for the Identification of Volatile Composition of the Leaves of Different Variants of Perilla L.
HU Yan1,2,DING You-fang1,WEN Chun-xiu3,XIE Xiao-liang3,ZHOU Qiao-mei3,LIU Yu-jun1,*
2010, 31(12):  159-164.  doi:10.7506/spkx1002-6630-201012037
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Purge and trap technique was used for enriching the volatile components of the leaves of different variants of Perilla L. prior to GC-MS analysis. Area normalization method was employed for the subsequent quantification. The results showed that there were significant differences in type and relative contents of volatile components among 4 samples belonging to 3 variants of Perilla L.. Totally 31 volatile components were identified in the samples, 3 of which, namely [Z]-3-hexenal, caryophyllene and santolina triene were contained in all of the samples. The main components of the leaves of wild growing P. frutescens (Linn.) Britt. var. acuta (Thunb.) Kudo included limonene (77.90%), caryophyllene (14.33%), [Z]-3-hexenal (4.9%), and 3-methyl-6-[1-methethyl]-2-cyclohexen-1-one (1.71%), those of the leaves of P. frutescens (Linn.) Britt. var. crispa (Benth.)H. W. Li caryophyllene (30.65%), limonene (24.60%), [Z]-3-hexenal (21.82%) and perilla aldehyde (17.70%), and those of the sample No.1 of P. frutescens (Linn.)Britt. var. frutescen from Anguo, Hebei province 5-ethylidene-1-methyl-cycloheptene (52.79%), [Z]-3-hexenal (19.98%), caryophyllene (13.60%) and perilla aldehyde (9.46%), and those of the sample No.2 of P. frutescens (Linn.)Britt. var. frutescen from Linshan, Guangxi autonomous region perilla aldehyde (31.86%), 5-ethylidene-1-methyl-cycloheptene (31.68%), [Z]-3-hexenal (21.50%) and caryophyllene (10.47%).

GC with Flame Photometric Detection for the Simultaneous Determination of Organophosphorus Pesticide Multiple Residues in Pu-erh Tea
KOU Ting-ting1,XU Kun-long2,ZHANG Ling-zhi1,YANG Jun3,WANG Deng-liang1,*,CHEN Yu-fen3
2010, 31(12):  165-168.  doi:10.7506/spkx1002-6630-201012038
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A method using gas chromatography (GC) with flame photometric detection was developed for the simultaneous determination of 9 organophosphorus pesticide multiple residues in tea matrices. A total of 30 Pu-erh tea samples from 5 producing areas in Yunnan province (half raw tea and half ripe tea, with 3 replicates for each area) were determined by the developed method in order to provide experimental data for safety assessment. Samples were extracted with ethyl acetate under the assistance of ultrasonic, followed by clean-up on an activated carbon cartridge. Quantification was achieved using external standard method. Mean recoveries for 9 analytes at 3 spike levels ranged from 71.1% to 113.8%, with a RSD between 0.9% and 13.3%. The developed method exhibited limits of detection ranging from 1.0 to 2.5μg/kg. Dichlorovos, acephate, dimethoate, fenitrothion, malathion, quintozene and triazophos were all detected in selected Pu-erh tea samples. Among them, the detection rates of fenitrothion and dimethoate were higher, but the contents were both lower than the EU limit standard. In terms of organophosphorus pesticide multiple residues in Pu-erh tea, it is safe for drinking.

Development of an Indirect Competitive ELISA for Determination of Terbutaline Residue in Pork
SUN Hai-xin1,LING Hong-li1,*,ZHANG Yu-lan2,XI Ri-mo2,LI Zhi-zhong1,GAO Ya-dong1,DONG Rui-e1,ZHAO Yu-hui1
2010, 31(12):  169-173.  doi:10.7506/spkx1002-6630-201012039
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The specific antibodies against terbutaline prepared in our previous studies were used to develop an indirect competitive ELISA for the determination of terbutaline residue in pork. The sensitivity, accuracy, precision and specificity of the method were measured, followed by a comparison with HPLC method. The developed ELISA exhibited good linearity over the concentration range from 1 to 100 ng/mL, a sensitivity of 0.47 ng/mL, a limit of detection of 1 ng/mL and a spike recovery range from 80% to 99%. Cross-reactivities between the antibodies against terbutaline prepared and clenbutarol or salbutamol were 94.9% and 93.9%, respectively, and those between the antibodies against terbutaline prepared and ractopamine or adrenaline were both less than 0.01%. The developed HPLC method exhibited a linear range from 10 to 200μg/mL, a limit of detection of 1μg/mL and a spike recovery range from 79.2% to 94.8%. The developed ELISA exhibited higher sensitivity and specificity than the developed HPLC, whereas the stability of the former was inferior to that of the latter. Their accuracies were similar.

Determination of Alkylphenols and Alkylphenol Ethoxylates in Tropical Fruits by LC with Ultrasonic-assisted Extraction
LU Dai-zhu
2010, 31(12):  174-177.  doi:10.7506/spkx1002-6630-201012040
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A liquid chromatographic (LC) method based on ultrasonic-assisted extraction was presented for the determination of alkylphenols and alkylphenol ethoxylates residues in tropical fruits. The determination of samples by the method developed was achieved through the steps of extraction, condensation, chromatographic separation on a C18 column and fluorescence detection. Optimum conditions for the ultrasonic-assisted extraction of samples were investigated. Calibration curves for alkylphenol ethoxylates and nonyl phenol both exhibited good linearity over the concentration range from 0.5 to 50 μg/mL. Detection limits were 0.04 mg/kg for alkylphenol ethoxylates and 0.008 mg/kg for nonyl phenol. Mean recoveries for alkylphenol ethoxylates and nonyl phenol at 3 spike levels ranged from 92% to 102% and from 75% to 92%, respectively. In conclusion, this method is rapid, sensitive and accurate and meets the requirements of pesticide residue determination.

GC Determination of 2,3,5-Triiodobenzoic Acid Residue in Vegetables
ZHOU Yan-ming,FU Ting,HU Rui
2010, 31(12):  178-181.  doi:10.7506/spkx1002-6630-201012041
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A gas chromatographic (GC) method was developed for the determination of 2,3,5-triiodobenzoic acid (TIBA) in vegetables. The main steps in sample preparation prior to the injection of processed samples into a GC system equipped with an electron capture detector consisted of acidification with 0.1 mol/L hydrochloric acid, extraction with methylene dichloride under ultrasonic assistance, methylation with trimethylsilyl diazomethane and clean-up on a florisil solid phase extraction (SPE). Retention time was used for qualification and external standard method for quantification. Some figures of merit the method developed including sensitivity, accuracy and precision were evaluated. This method exhibited a limit of detection of 0.001mg/kg for TIBA. Mean recoveries for the analyte in 6 vegetable matrices ranged from 70% to 95.7%. These results suggest that this method is reliable, sensitive, simple and convenient and can provide useful references for the establishment of a national standard method for the determination of TIBA.

GC-MS Analysis of Fatty Acid Composition of Silkworm Male Moths and Pupa
Chen Zhi-yi
2010, 31(12):  182-184.  doi:10.7506/spkx1002-6630-201012042
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In this study, we used GC-MS to analyze the fatty acid composition of essential oils extracted from silkworm male moths and pupa with supercritical CO2 after methylation. Fifteen fatty acids were separated and identified in silkworm male moths oil, containing 54.52% of saturated fatty acids (SFA) and 6.89% of mono-unsaturated fatty acids (MUFA) and 38.63% of polyunsaturated fatty acids (PUFA), among whichs alpha linlenic acid presented the highest relative content (up to 36.71%). Fourteen fatty acids were identified in silkworm pupa oil, among which, the relative content of linoleic acid was the highest (up to 39.03%), followed by alpha linlenic acid (33.22%); SFA, MUFA and PUFA accounted for 25.73%, 2.12% and 72.25%.

Simultaneous Analysis of Melamine and Cyanuric Acid in Chicken Tissues by High Performance Liquid Chromatography-Tandem Mass Spectrometry
WU Cai-mei,BAI Jie,JIA Gang,ZHANG Ke-ying*,DING Xue-mei,BAI Shi-ping,
2010, 31(12):  185-192.  doi:10.7506/spkx1002-6630-201012043
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A high performance liquid chromatography-tandem mass spectrometric (HPLC-MS/MS) method was developed for the quantification of melamine (MEL) and cyanuric acid (CYA) in chicken tissues. A sample preparation procedure comprising extraction with acetonitrile mixed with water at a ratio of 70:30 (V/V), the removal of lipids with n-hexane, centrifugation at 7000 r/min, thorough mixing of the supernatant and acetonitrile (1:1, V/V), centrifugation at 10000 r/min for the precipitation of protein and filtration through a 0.22μm membrane but excluding clean-up was used prior to HPLC-MS/MS analysis, resulting in a great reduction of the time required for sample preparation. Multiple reaction monitoring (MRM) mode was selected and internal standard isotope dilution method was used for quantification in order to improve the accuracy and quantitative linearity of the method. Calibration curves for MEL and CYA exhibited good linearity over the concentration range from 1 to 500 ng/mL, with R2 values of both larger than 0.999. Average recoveries ranged from 87.76% to107.89% for MEL and from 87.31% to 106.05% for CYA, with relative standard deviations (RSDs) ranging from 0.58% to 2.78% for MEL and from 1.26% to 4.33% for CYA at the spike levels of 0.1, 1 mg/kg and 5 mg/kg. The limits of detection (LOD) of MEL and CYA were 4 ng/kg and 2 ng/g, respectively. Therefore, this method is simple, rapid and accurate and is most suitable for the quantification of MEL and CYA in chicken tissues.

PCR Detection of Escherichia coli O157 in Food and Sequencing of wzy Gene
LI Rui,ZHANG Zhong-mei,DAI Shi-jiao,SUN Yan-feng,HUANG Wan-qi*
2010, 31(12):  193-196.  doi:10.7506/spkx1002-6630-201012044
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A strain of Escherichia coli O157:H7 was isolated from fresh beef and named EC5. EC5 was subjected to PCR amplification and sequencing of full-length wzy gene. There was a 100% similarity between the wzy gene sequence of EC5 and that of Escherichia coli O157:H7 EDL933. Specific primers were designed based on the conserved locus of wzy gene sequences known from NCBI GenBank database for differentiating O157 strains from non-O157 ones by PCR assay. Our findings demonstrate that the wzy gene amplified by PCR is highly specific and provides a promising marker gene for the detection of Escherichia coli O157:H7.

GC-MS Analysis of Fatty Acid Composition of Different Organic Solvent Extracts from Cornus wilsoniana Seeds
PENG Hong,HAN Dong-ping,LIU Yu-huan,ZHANG Jin-sheng,RUAN Rong-sheng
2010, 31(12):  197-199.  doi:10.7506/spkx1002-6630-201012045
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Cornus wilsoniana seeds were extracted with absolute ethanol, acetone, hexane, petroleum ether and ethyl acetate respectively, and the extracts obtained were decolorized with active carbon prior to GC-MS analysis. Palmitinic acid, oleic acid and linoleic acid were the predominant compounds in ethanol and acetone extracts. Among them, the relative content of linoleic acid was the highest, as high as more than 52% and that of oleic acid was the lowest, less than 8.2%. The main compounds in respective methyl esterification products of hexane, petroleum ether and ethyl acetate extracts were palmitinic acid, steric acid, oleic acid and linoleic acid. Among them, the relative content of oleic acid was the highest, as high as more than 42%, followed by linoleic acid. The relative contents of total unsaturated fatty acids in hexane, petroleum ether and ethyl acetate extracts were all more than 70%. No triunsaturated fatty acids were detected in any of the 5 extracts.

HPLC with Matrix Solid-phase Dispersion Followed by Solid-phase Extraction for the Determination of Melamine in Complicated Matrices
WANG Hong-tao,DONG Jing,GONG Xiao-ming,DING Kui-ying,YU Jin-ling
2010, 31(12):  200-202.  doi:10.7506/spkx1002-6630-201012046
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This paper reports a high-performance liquid chromatographic (HPLC) method based on matrix solid-phase dispersion followed by solid-phase extraction for the determination of melamine in complicated matrices such as animal feeds, chocolate products, meat products, and so on. The method developed had good immunity to the interferences of lipids and proteins and exhibited a lower false positive rate. Two calibration curves (detected at 215 or 240 nm) for melamine exhibited good linearity over the concentration range from 0.5 to 8.0μg/mL, with a correlation coefficient of more than 0.9995. The limit of detection of this method was 0.5 mg/kg.

Analysis & Detection
Use of Molecular Imprinted Monolithic Column for the HPLC Determination of Melamine in Dairy Products
LI Zhi-wei,LIU Jia,HUO Yun-xia,CUI Zhe,LIU Fang-fang
2010, 31(12):  203-205.  doi:10.7506/spkx1002-6630-201012047
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A molecular imprinted monolithic column was prepared for providing stationary phase for the HPLC analysis of melamine in dairy products, in which the mobile phase was a mixture of 10% aqueous methanol solution and 0.1% aqueous acetic acid solution (5:95, V/V) at a flow rate of 0.5 mL/min and the detection wavelength was set at 240 nm. There was a good linear relationship between HPLC peak area and melamine concentration over the range from 1.0 to 100.0 μg/mL (r = 0.9987). Average recoveries for melamine in a blank sample spiked at 3 levels were between 87.0% and 100.5%, with a RSD of less than 5% (n = 6). In conclusion, this method is easily operated, highly selective and has no requirement of complicated sample pretreatment and is applicable for the determination of melamine residue in dairy products.

Determination of Nitrofuran Metabolites in Fish and Fry Products by High Performance Liquid Chromatography-Tandem Mass Spectrometry
YANG Lin1,FU Hong2,LIU Qiang2
2010, 31(12):  206-211.  doi:10.7506/spkx1002-6630-201012048
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In this study, we presented a high performance liquid chromatography-tandem mass spectrometric (HPLC-MS/MS) method for determining 4 nitrofuran metabolites in 115 fish or fry products, namely 1-aminohydantoin hydrochloride (AHD), 3-amino-5-morpholinomethyl-2-oxazolidineone (AMOZ), 3-amino-2- oxazolidinone (AOZ) and semicarbazide (SEM). Samples were subjected to hydrolysis, derivation and clean-up prior to HPLC-MS/MS analysis. The analysis was carried out in the multi reaction monitoring (MRM) mode and internal standard isotope dilution method was used for quantification. Calibration curves for the analytes exhibited good linearity over the concentration range from 0.5 to 20 ng/mL and their limits of detection were all 0.25μg/kg. Average recoveries for them spiked at 3 levels ranged from 89.0% to 117.2%, with a RSD of less than 10%. Nitrofuran metabolites residues in fry were found much higher than those in adult fish. The detection rate of AOZ in large yellow croaker fry was 62%, with a maximum residue of 3890μg/kg; however, for large yellow croaker, the detection rate and the maximum residue were both comparatively lower, 17% and 2.81μg/kg, respectively. Less nitrofuran metabolites residues were detected in fresh water fish than in their sea counterpart.

Determination of Glucocorticoid Residues in Pork by HPLC-MS/MS
NIU Jin-yang, SHI Hong-xia
2010, 31(12 ):  212-214.  doi:10.7506/spkx1002-6630-201012049
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A sensitive and rapid method using HPLC-MS/MS was proposed for the determination of 8 glucocorticoid residues in pork. Samples were extracted with methanol and cleaned up on a solid-phase extraction column before HPLC-MS/MS analysis. Optimum sample pretreatment conditions and mass spectral parameters were investigated. Calibration curves for 8 glucocorticoids showed good linearity over the concentration range from 0.5 to100μg/kg. Average recoveries for them spiked at 3 levels were between 78% and 101%. The method developed exhibited a limit of detection for all the analytes ranging from 0.2 to 2μg/kg. The determination of real samples was carried out using this method and satisfying results were obtained. This method is simple, rapid, sensitive and highly selective and is worth popularizing among food inspection organizations.

A HPLC Method for the Determination of Sialic Acid in Antler Velvets
LU Xiu-xiu1,LI Gang2,3,XUE Dong-hua1,ZHANG Long2,4,*
2010, 31(12):  215-218.  doi:10.7506/spkx1002-6630-201012050
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A cationic exchange-HPLC method was presented for determination of sialic acid in antler velvets. Hydrochloric acid was used to hydrolyze samples. The optimum determination conditions based on the use of ZORBAX 300-SCX cationic exchange column were determined as follows: mobile phase, a mixture of acetonitrile and 0.1% phosphoric acid (90:10, V/V) at a flow rate of 1.0 mL/min; sample loading amount, 10.0 μL; and detection wavelength, 205 nm. There was good linearity between peak area and sialic acid concentration within the range from 5 to 100μg/mL. The detection limit (RSN = 3) of the method developed was 0.03 g/kg for sialic acid. The average recovery for sialic acid was 83.4%, with a RSD of 4.9% (n = 6). This method is applicable for the determination of sialic acid in antler velvets and antler velvet products.

HPLC-MS/MS Determination of Florfenicol and Florfenicol Amine Residues in Fish
LI Ying-ying,SONG Yong-qing,ZHAO Rong,NIU Jin-yang,GUO Wen-ping
2010, 31(12 ):  219-222.  doi:10.7506/spkx1002-6630-201012051
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A HPLC-MS/MS method was established for the simultaneous determination of florfenicol (FF) and florfenicol amine (FA) residues in fish. Samples were extracted with alkalinified ethyl acetate and cleaned up by liquid-liquid extraction with n-hexane. Both positive and negative electrospray ionization sources were selected and multiple reaction monitor (MRM) mode was used. Internal standard method was used for quantification. The limits of detection of the method established were 1 μg/kg for FF and 5μg/kg for FA. Average recovery rates for FF and FA spiked at low, medium and high levels ranged from 87.0% to 110.4%, with a relative standard deviation of less than 6.2%. The method is simple, fast, efficient and highly selective.

Analysis of Chemical Composition of Volatile Oil from Daylily
HU Yu-sen,YANG Ji-tao,YANG Peng
2010, 31(12):  223-225.  doi:10.7506/spkx1002-6630-201012052
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This paper reports the analysis of chemical composition of volatile oil from daylily, in which steam distillation was used for the extraction of volatile oil from daylily, followed by GC-MS separation and identification and quantification of relative content of each identified compound by peak area normalization. Totally 100 compounds were separated, of which, 36 were identified and altogether accounted for 95.68% of the total volatile oil and 3-furanmethanol was the most predominant compound, with a relative content of up to 76.17%.

Determination of Existing Forms of Bromine in Beverage by IC-ICP-MS
LIN Li1, CHEN Yu-hong2,WANG Hai-bo3
2010, 31(12):  226-228.  doi:10.7506/spkx1002-6630-201012053
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In this study, we presented a method based on ion chromatographic separation and ICP-MS detection for the determination of two existing forms of bromine in beverage, i.e., BrO3- and Br-. The limits of detection of the presented method were 0.1μg/L for BrO3- and 0.2μg/L for Br-. Spike recovery tests were carried out to evaluate the accuracy and precision of this method, and average recoveries for BrO3- in 3 different matrices spiked at 3 levels ranged from 88.1% to 106.4%, with a relative standard deviation from 1.52% to 3.83% (n = 6). This method was used to analyze some commercial beverages, and no BrO3 - was detected in any of them.

Freshness Evaluation of Juicy Peach by Electronic Nose
JIANG Lin-lin1,PAN Lei-qing1,*,TU Kang1,YANG Hong-xian1,QIAN Zhao1,HAN Dong-hai2
2010, 31(12):  229-232.  doi:10.7506/spkx1002-6630-201012054
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In this study, a portable electronic nose PEN3 was used for the aroma analysis of Jiubao juicy peach, an early-ripening cultivar in order to provide experimental references for the evaluation of its freshness. Dynamic aroma sampling was achieved using PEN3 and the response values of the instrument were obtained. This was followed by data analysis using principal component analysis (PCA) and linear discrimination analysis (LDA). The results showed that the use of LDA was able to better discriminate peaches on the 1st, 2nd to 4th, and 5th to 7th days of postharvest storage in polyethylene bags under the conditions of (20 ±0.5 )℃ and 65%-70% relative humidity. According to cross-validation analysis, the discrimination accuracy among these samples stored for different storage periods was as high as 91%. Meanwhile, it was indicated by loading analysis that sensors W1S, W2S and W2W played a central role in evaluating the freshness of juicy peach, which provides useful evidences for the optimization of sensors and exploration into a simple and convenient non-destructive technique for the evaluation of juicy peach freshness.

Vortex-mixing Extraction and Ultra Performance Liquid Chromatography for the Analysis of 6 Antioxidants in Fatty Food Simulant Olive Oil
LIN Qin-bao1,LI Xiao-mei1,SONG Huan2,LI Bo1
2010, 31(12):  233-238.  doi:10.7506/spkx1002-6630-201012055
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An efficient and simple analytical method has been developed for the determination of 6 phenolic antioxidants, namely 4,4'isopropylidendiphenol (BPA), tert-butyl-4-hydroxyanisole (BHA), 2,6-di-tert-butyl-4-hydroxy-methylphenol (Ionox100), 2,6-di-tert-butyl-p-cresol (BHT), 2,4,6-tri-tert-butylphenol (TTBP) and 2,2 '-methylenebis-(6-tert-butyl-4-ethylphenol) (AO 425) in fatty food simulant olive oil. Two methods, namely extraction with methanol on a vortex mixer followed by concentration using a rotary evaporator (hereinafter referred to as Method 1) and extraction with cyclohexane/ethyl acetate mixture (1:1, V/V) on a vortex mixer followed by gel permeation chromatographic concentration (hereinafter referred to as Method 2) were separately used for sample pretreatment before ultra performance liquid chromatographic (UPLC) analysis. The merits of figure of the developed method were as follows: respective limits of detection (LODs) for BPA, BHA, Ionox100, BHT, TTBP and AO 425, 0.06, 0.04, 0.01, 0.03, 0.06 mg/L and 0.01 mg/L; correlation coefficients of calibration curve of the analytes, larger than 0.998, indicating good linearity; and respective average spike recoveries for the analytes in samples pretreated by Methods 1 and 2, larger than 83.0% and 56.8%, with RSDs of smaller than 7.5% and 8.4%. This method was used to determine some commercial edible oils from different plants, and only BHT was detected in all of them, the contents of which were all much lower than the Chinese national specific migration limit.

Packaging & Storage
Effect of Frozen Storage Temperature on the Quality of Rachycentron canadum Fillets
XIA Xing-zhou1,2,HONG Peng-zhi1,*,ZHONG Can-hua3,GAO Jia-long1,WU Wen-long1,LIU Huan-ming1,ZHANG Chao-hua1
2010, 31(12):  239-243.  doi:10.7506/spkx1002-6630-201012056
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Rachycentron canadum fillets were stored at -10, -18 or -30 ℃ for a 90-day period of time in order to investigate the effect of different frozen storage temperatures on the physicochemical properties, textural characteristics and sensory attributes of Rachycentron canadum fillets. Temperature had a significant effect (P<0.05) on thawing loss, cooking loss, saltextractable protein content, Ca2+-ATPase activity and TBA value during frozen storage. Thawing loss, cooking loss and TBA value increased, while salt-extractable protein content and Ca2+-ATPase activity decreased with increasing storage period and temperature. This suggests the decrease of water holding capacity, the increase of protein denaturation degree and the acceleration of lipid oxidation. The texture profile analysis (TPA) showed that the hardness and chewiness of frozen fish fillets increased significantly (P<0.05), while the resilience decreased significantly (P<0.05) with prolonged storage period; the hardness and chewiness decreased while the resilience value increased with decreasing temperature. The results of sensory analysis that the sensory quality of fish fillets deteriorated due to frozen storage and that higher temperatures resulted in aggravated quality deterioration. The optimal storage temperature was - 30 ℃.

Antioxidant Effect of BHT on Prepared Chicken Livers under Simulated Circulation Conditions
SUN Ling-xia,ZHAO Gai-ming*,LIU Yan-xia,ZHANG Qiu-hui,CAI Hao-shuai
2010, 31(12):  244-246.  doi:10.7506/spkx1002-6630-201012057
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Prepared chicken livers were treated with different doses of BHT, i.e., 0.05, 0.10, 0.15 g/kg and 0.20 g/kg, followed by storage under frozen and refrigerated temperature conditions as simulated circulation environments. Lipid oxidation in the treated chicken livers were evaluated by determining acid value (AV), peroxide value (POV) and thiobarbituric acid value (TBA) after different storage periods. Results showed that lipid oxidation occurred mainly in the first 30 days and after 30 days, the late period of lipid oxidation began. And 0.15 g/kg had the best antioxidant effect among four doses tested.

Clove Oil Anesthesia for the Improvement of Survival Rate of Crayfish
XIE Hui-ming,BIAN Hui-xi,YANG Yi,ZHANG Wen-cheng,LIN Chun-ming,GAO Xiang-lan
2010, 31(12):  247-250.  doi:10.7506/spkx1002-6630-201012058
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In an effort to improve the survival rate of crayfish during long-distance transport, clove oil, MS-222 (3-aminobenzoic acid ethyl ester methanesulfonate) and ethyl ether were used alone for the anesthetic treatment of crayfish, and clove oil was the selected anesthetic agent for the studies carried out subsequently, in which, the effect of varying clove oil concentrations (10, 20, 40, 80, 160, 320 mg/L) on the oxygen consumption and survival rate of crayfish was examined. Crayfish was anesthetized within 10 min post-treatment of clove oil at 20-80 mg/L and the survival rate was more than 96%. The optimal clove oil concentration for keeping crayfish alive during storage at 25-30 ℃ was 60 mg/L, resulting in an increase by 9% in survival rate when compared with post-20 h storage unanesthetized crayfish.

Frozen Storage of Chinese Bayberry at Glass Transition Temperature
CHEN Qin,SHAO Xing-feng*,WANG Wei-bo,CHAI Li-jie
2010, 31(12 ):  251-254.  doi:10.7506/spkx1002-6630-201012059
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The purpose of this study was to measure the glass transition temperature (Tg) of Chinese bayberry (Myrica rubra Sieb. & Zucc. cv. Dongkui) and to use the temperature to freeze Chinese bayberry for preservation purpose in practice. It was found that the starting point of partial glass transition temperature (Tg') of Chinese bayberry was -44 ℃, the midpoint -42 ℃ and the termination point -39.2 ℃. Compared with -18 ℃, the storage temperature of -40 ℃ (simulated glass transition preservation) reduced the post-thawing juice loss and maintained a higher soluble solids content (SSC); no significant differences in pH and titratable acid content, however, were observed between Chinese bayberries stored at both the temperature. Instrumental analysis and sensory evaluation both showed that -40 ℃ was more conducive to maintaining the texture quality of Chinese bayberry.

Fresh-Keeping Effect of Nano-Titania/Corn Starch Compound Coating on Cherry Tomato
SONG Xian-liang,YE Sheng-ying,HUANG Wei,ZHOU Yi
2010, 31(12):  255-259.  doi:10.7506/spkx1002-6630-201012060
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Polyvinyl pyrrolidone (PVP), a highly effective dispersant, and ultrasonic technique were used for the homogeneous dispersion of nano-titania in corn starch paste to yield a compound coating. The coating was used to treat cherry tomato and the weight loss, the contents of soluble solids, VC and total acid, hardness and percentage of rotten fruits of treated cherry tomato during storage were periodically measured in order to investigate its fresh-keeping effect. The results showed that with increasing amount of added nano-titania, weight loss, soluble solid content and percentage of rotten fruits first decreased and then increased, but hardness and the contents of VC and total acid displayed an opposite change pattern. The compound coating with added nano-titania at 0.025% (m/m, on the basis of the dry weight of corn starch) showed the best fresh-keeping effect on cherry tomato; the weight loss, soluble solid content and percentage of rotten fruits of cherry tomato treated with it after 11 days of storage were reduced by 28.6%, 12.7% and 78.8%, respectively, when compared with untreated cherry tomato, whereas hardness and the contents of VC and total acid exhibited 1.33-, 1.12- and 1.34-fold increases, respectively. Our findings suggest that nano-titania appear to have the potential to be applied for the fresh-keeping of fruits.

A Comparative Study of the Effects of High Energy Electron Beam and 60Co γ-ray Irradiations on the Sprout Inhibition and Fresh-keeping of Garlic
YANG Jun-li1,2,QIAO Yong-jin1,*,WANG Hai-hong1,CHEN Zhao-liang1,QIAO Xu-guang2
2010, 31(12):  260-265.  doi:10.7506/spkx1002-6630-201012061
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In China, the good irradiation practice for the sprout inhibition of garlic has had no definite division between 60Coγ-ray and electron beam irradiations, both of which have different penetrating ability and irradiation energy. To figure out their sprout inhibition and fresh-keeping effects, the inner bud growth status and several physiological indexes of garlic irradiated byγ-ray or electron beam at the dosages of 200, 500 Gy and 800 Gy respectively were assessed during storage period (5-25 ℃, RH 70%-85%). The results showed that both the irradiations effectively inhibited sprouting, and electron beam had better effect than 60Coγ-ray at the same irradiation dosages. Both the irradiations at 200 or 500 Gy inhibited respiration and decreased weight loss but had little effect on the color of the outer skin of garlic bulb and garlic flavor; garlic irradiated by γ-ray or electron beam at 800 Gy exhibited strengthened respiratory intensity, increased weight loss and severe shrinkage. Considering both nutritional and commercial qualities, electron beam irradiation at 200 Gy and 60Coγ-ray irradiation at 500 Gy appear to be both better choices for the sprout inhibition and fresh-keeping of garlic.

Changes in Aroma Components of Nanguo Pear during Post-harvest Storage at 20 ℃
FENG Fan1,2,XIN Guang1,2,*,ZHANG Bo2,LI Tie-chun2,LI Shu-qian1,2
2010, 31(12):  266-269.  doi:10.7506/spkx1002-6630-201012062
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In this study, solid-phase microextraction and GC-MS were employed to measure the aroma components of Nanguo pear stored at 20 ℃. The results showed that only 6 aroma components were detected in Nanguo pear in the first 10 days of post-harvest storage. The number of detected aroma components of Nanguo pear was 13 on the 15th day of storage, the maximum number, 18, appeared on the 20th day, and that was lowered to 12 on the 25th day. Totally 19 compounds were identified during he 25-day storage, of which, ethyl acetate (1.49%), butanoic acid, ethyl ester (7.48%), acetic acid, 2-methylpropyl ester (1.43%), hexanoic acid, methyl ester (1.46%), hexanoic acid, ethyl ester (41.76%), acetic acid, hexyl ester (11.78%), 2-octenoic acid, ethyl ester (1.07%), octanoic acid, ethyl ester (6.73%) and alpha-farnesene (21.6%) were the major compounds identified on the 20th day.

A Model-based Study of Formulation of Compound Preservatives for Prolonging the Shelf Life of Dried Persimmon
CHEN He,WANG Lei*,WANG Yong
2010, 31(12):  270-273.  doi:10.7506/spkx1002-6630-201012063
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Nipagin A, propyl 4-hydroxybenzoate and natamycin were formulated and used to prolong the shelf life of dried persimmon. Based on orthogonal array design, the following regression model describing the shelf life of dried persimmon (y) as a function of the final concentrations of nipagin A (Z1), propyl 4-hydroxybenzoate (Z2) and natamycin (Z3) in aqueous solution: lny = 5.312 + 1776.5 Z1 + 300.8 Z2 + 217.7 Z3 -2244800 Z1 Z2. The lack-of-fit tests demonstrated that the accuracy of the model was more than 99%. According to response surface and single-factor linear analyses, when Z2 was less than 0.079 g/100 mL, Z1 and Z2 had positive correlation with y; when Z2 was more than 0.079 g/100 mL, Z1 and Z2 had negative correlation with y.

Modeling of Lipid Oxidation and Storage Life Prediction of Walnut (Carya cathayensis Sarg.)
YANG Hu-qing,WU Feng-hua*
2010, 31(12):  274-278.  doi:10.7506/spkx1002-6630-201012064
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The time-course of lipid oxidation determined by peroxide value and acid value, and the sensory quality of walnut (Carya cathayensis Sarg.) stored at different temperatures (2, 12, 22, 32 ℃) were evaluated, and the separate kinetic models of peroxide value and acid value with respect to storage time at different storage temperatures were established based on Arrhenius equation, so as to predict and control the quality of walnut during storage. Results indicated that peroxide value and acid value increased with prolonged storage time and increasing storage temperature resulted in a prompt increase in both the values. The sensory quality of walnut decreased with prolonged storage time and dropped promptly with increasing storage temperature. Changes in the peroxide value and acid value of walnut perfectly followed first order reaction model and Arrhenius equation (R2 >0.9). The predicted storage life had a relative error within ±10% when compared with the experimental results. In conclusion, the storage-life of walnut stored at temperatures ranging from 2 to 32 ℃ can be predicted according to its peroxides value and acid value.

Fresh-keeping Effect of Ethanol Extracts of Four Species of Plants on Eggs
WANG Chan,MA Jing-zhong *,YUAN Chao
2010, 31(12):  279-283.  doi:10.7506/spkx1002-6630-201012065
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To develop natural herbal antistaling agents, the fresh-keeping effects of separate ethanol extracts of Ginkgo biloba L., Lonicera maackii [Rupr.] Herder (honeysuckle), Taraxacum mongolicum and Cinnamomum cassia Presl on eggs were investigated. Eggs were immersed in the above extracts for 5 min, dried, sealed in bags and stored at 25 ℃ and relative humidity 50% - 70%. The quality of the eggs was periodically evaluated by sensory evaluation and the determination of some physicochemical indexes during storage. The results showed that honeysuckle extract had the best fresh-keeping effect and the percentage of fresh egg was 100% after 35 days of storage, with weight losing rate 2.67%, yolk index 0.358, the content of dense albumen 55.65%, Haugh unit 50.247, and the height of air chamber 2.13 mm.

Effect of Compound Improvers on Anti-retrogradation of Steamed Bread after Frozen Storage
PAN Li-jun,FANG Kun,MA Dao-rong,SHOU Jia-fei
2010, 31(12):  284-287.  doi:10.7506/spkx1002-6630-201012066
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The phenomenon of aging may happen to steamed bread stored at low temperatures, which has been shown to seriously affect the quality and flavor of steamed bread. In the production process of steamed bread, different enzyme preparations, emulsions and starches were added to improve the percentage changes in the hardness and resilience of steamed bread, and α -amylase, diacetyl tartaric acid esters of mono- and diglycerides (DATEM) and modified potato starch were selected. The orthogonal array optimization showed that the optimum amounts of the selected substances for the improved sensory score and precentage changes in the hardness and resilience of steamed bread were found to be: α-amylase 0.3%, DATEM 0.7% and modified potato starch 3%.

Numerical Simulation of Pre-cooling Process of Longan in Small Packing Box
MENG Zhi-feng1,SHEN Wu-xiong1,XIANG Hong1,YANG Zhou2,ZHOU Jia-hua1,*
2010, 31(12):  288-292.  doi:10.7506/spkx1002-6630-201012067
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Finite element analysis was used to simulate the effects of cool air temperature and velocity on the pre-cooling process of longan in a small packing box in order to explore the temperature profile of longan located at different space positions. The simulated data agreed with the experimental ones well. The biggest temperature difference between the simulated and the experimental data was around 3.5 ℃. When the cool air velocity used was 1 m/s, longan cooled rapidly and less energy was consumed and the 7/8 cooling time required was at least 35 min at 5 ℃ cool air temperature.

Technology Application
Application of Fish Scales Collagen Hydrolysate for the Production of Cake and Sausage
SONG Yong1,WANG Hai-yan2,LI Xiu-liang1,LEI Hong1,*,LI Chong-wei1
2010, 31(12):  293-296.  doi:10.7506/spkx1002-6630-201012068
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Fish scales collagen hydrolysate was added in cake baking and sausage processing in order to study its effects on the quality of cake and sausage. The results showed that proper addition of fish scales collagen hydrolysate could enhance the yield and the specific volume of cake. As for sausage, proper addition of fish scales collagen hydrolysate could increase the yield and improve the water holding capacity. Moreover, cake and sausage with added fish scales collagen hydrolysate were both good in sensory characters. In this study, the optimal amounts of added fish scales collagen hydrolysate in cake and sausage were 3% and 2%, respectively.

Optimization of Processing Process of Kudzu Yoghurt
HUANG Cheng1,YIN Hong1,ZHOU Chang-chun2,3,LEI Qi-neng3
2010, 31(12):  297-300.  doi:10.7506/spkx1002-6630-201012069
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Main materials, namely kudzu roots from the west of Hunan province and skimmed milk powder, were processed into a yoghurt beverage with the additions of adjuncts including high fructose corn syrup, xanthan and sodium carboxymethyl cellulose. Some crucial process conditions for yoghurt making were studied. The results showed that the optimum compound color fixatives contributing to the maintenance of the milk-white color of kudzu root juice was composed of 0.1% citric acid and 0.1% VC. The optimum process for yoghurt making consisted of the following steps: preparation of reconstructed milk by thoroughly dispersing skimmed milk powder in water (1:8, m/V), blending of reconstructed milk and kudzu root juice (2:5, V/V), addition of 10% high fructose corn syrup, 0.05% xanthan and 0.1% sodium carboxymethyl cellulose to the blend, 95 ℃ heating for 10 min for sterilization and fermentation with Lactobacillus bulgaria/Streptococcus thermophilus mixture (1:1) at 43 ℃ for 5 h, and the product processed through these steps exhibited a nice sweet-and-sour balance and a full-bodied flavor and were rich in nutrients.