Loading...

Table of Content

25 February 2016, Volume 37 Issue 4
Processing Technology
Optimization of Adsorption Conditions for Forchlorfenuron in Kiwifruit Juice by Inactivated Yeast
YANG Lixia, YUE Tianli, YUAN Yahong, LONG Fangyu, WANG Zhouli
2016, 37(4):  1-6.  doi:10.7506/spkx1002-6630-201604001
Asbtract ( 578 )   HTML ( 7)   PDF (2375KB) ( 229 )  
Related Articles | Metrics

The adsorption of forchlorfenuron in kiwifruit juice was studied by inactivated yeast. Based on single-factor
experiments, Box-Behnken response surface methodology (RSM) was adopted to study the effects of the key factors
(inactivated yeast dosage, initial concentration of forchlorfenuron, and adsorption time) on adsorption efficiency. The
influence of the adsorption on main quality indexes of kiwifruit juice was also studied. The results indicated that the optimum
adsorption conditions were as follows: inactivated yeast dosage, 28 mg/mL; initial forchlorfenuron concentration, 0.2 μg/mL;
and adsorption time, 3 h. Experiments conducted under the optimized conditions gave an adsorption rate of 97.02%, which
was consistent with the predicted value by RSM. The quality of kiwifruit juice was not significantly affected by treatment
with inactivated yeast (P > 0.05).

Optimization of Polyphenols Extraction from Quinoa Grains by Response Surface Methodology and Differences in Polyphenol Content among Different Varieties
QUE Miaolin, JIANG Yurong, CAO Meili, CHEN Qi, WEI Shuying, LU Guoquan
2016, 37(4):  7-12.  doi:10.7506/spkx1002-6630-201604002
Asbtract ( 1068 )   HTML ( 15)   PDF (2358KB) ( 251 )  
Related Articles | Metrics

The optimum extraction conditions of polyphenols from quinoa grains were investigated in this study. On the
basis of single factor experiments, alcohol concentration, solid/liquid ratio and extraction temperature were selected for
a three-factor, three-level Box-Behnken experimental design. In addition, Design-Expect 8.0 software was employed to
analyze the experimental data and the response surface methodology was applied to optimize the extraction conditions. The
results suggested that optimal extraction conditions were determined as 56% ethanol as the extraction solvent, an extraction
temperature of 84 ℃ (water-based heating) and a solid/liquid ratio of 1:40 (g/mL). Under these optimized conditions, the
extraction yield of polyphenols from quinoa grains of the variety “PI634920” was 2.273 mg/g. The sequence of factors
affecting the extraction yield of polyphenols was as follows: alcohol concentration > extraction temperature > solid/liquid
ratio. Meanwhile, great variation in polyphenol content of quinoa grains was found among 20 different varieties, of which
the variety “PI596293” had the highest polyphenol content (2.72 mg/g).

Optimization by Response Surface Methodology of Ultrasound-Assisted Extraction and Antioxidant Activities of Polysaccharides from Glechoma longituba (Nakai) Kupr
LIU Xiaopeng, ZHANG Junxia, JIANG Ning, SONG Yizhi, XIANG Jiqian, WANG Qiushuang, WU Hao
2016, 37(4):  13-19.  doi:10.7506/spkx1002-6630-201604003
Asbtract ( 644 )   HTML ( 3)   PDF (2310KB) ( 944 )  
Related Articles | Metrics

In this study, we optimized the ultrasound-assisted extraction of polysaccharides from the dried aboveground
part of Glechoma longituba (Nakai) Kupr. by response surface methodology (RSM) based on central composite design
and measured the antioxidant activities of the extracted polysaccharides using 1,1-diphenyl-2-picrylhydrazyl (DPPH)
radical scavenging, 2,2’-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid radical (ABTS+·) scavenging, Fe2+ chelating
activity, ferric reducing antioxidant power (FRAP), and N,N-dimethyl-p-phenylenediamine radical scavenging methods.
The optimal extraction conditions were obtained as follows: pH, 7.2; liquid-to-solid ratio, 32:1 (mL/g); ultrasonic power,
270 W; and ultrasonic time, 8 min. Under these conditions, the yield of polysaccharides was 4.95%–5.12%. The extracted
polysaccharides exhibited powerful antioxidant activities. The DPPH radicals and ABTS+· scavenging activities, Fe2+
chelating activity, FRAP value and DMPD radical scavenging capacity were (0.51 ± 0.04) μmol Trolox equivalent
(TE)/mg, (0.69 ± 0.04) μmol TE/mg, (0.51 ± 0.29) μmol EDTA-2Na equivalent (EE)/mg, (3.45 ± 0.03) μmol TE/mg and
(0.17 ± 0.01) μmol TE/mg, respectively.

Optimization of Purification Process for Dihydroquercetin in Larch Roots by Response Surface Methodology
WANG Jiaqi, SONG Mingming, CHEN Kai, WANG Yueliang, DING Chuanbo, ZHENG Yinan, SHEN Lei, LIU Wencong
2016, 37(4):  20-24.  doi:10.7506/spkx1002-6630-201604004
Asbtract ( 474 )   HTML ( 5)   PDF (2432KB) ( 220 )  
Related Articles | Metrics

Objective: To optimize the purification conditions for dihydroquercetin in larch roots. Methods: Single factor
method combined with Box-behnkn response surface methodology was used to optimize four factors including solid/liquid
ratio, recrystallization temperature and time by establishing a model involving four independent variables at three levels each
based on dihydroquercetin purity. Results: The optimal purification conditions were determined as recrystallized for 20 h at
5 ℃ at a liquid-to-solid ratio of 1:12 (dihydroquercetin: water). Conclusion: The results of the study can provide scientific
basis for the determination of the purification process of dihydroquercetin in industrial production.

Effects of Different Drying Methods on Quality and Volatile Components of Pleurotus eryngii
TANG Qiushi1,2, LIU Xueming1,*, CHI Jianwei1, CHEN Zhiyi1, LI Shengfeng1, YANG Chunying1
2016, 37(4):  25-30.  doi:10.7506/spkx1002-6630-201604005
Asbtract ( 663 )   HTML ( 5)   PDF (1909KB) ( 339 )  
Related Articles | Metrics

In this study, the main components (protein, carbohydrate, crude fat, and total phenol), color, ash and volatile
components of the edible mushroom Pleurotus eryngii were monitored after hot air drying (HAD), vacuum freeze drying
(VFD), heat pump drying (HPD) and vacuum microwave drying (VMD) to unravel the effects of different drying methods
on the quality and volatile components of the mushroom. It was found that the contents of ash and protein of dried P. eryngii
by four drying methods changed only slightly, while the content of carbohydrate (13.56%) was the lowest in P. eryngii
dried by VMD, while the VFD-dried sample had the lowest contents of total phenol (39.97 μg/g) and crude fat (1.27%) but
it exhibited the least color changes. The changes in trehalose, an abundant monosaccharide in P. eryngii, caused by four
drying methods were in the order of HPD > VFD > HAD > VMD, while the changes in mannitol content caused by these
drying methods were in the order of HPD = VFD > HAD = VMD. The changes in volatile composition of P. eryngii caused
by four drying methods were also analyzed. A total of 68 volatile compounds were detected, including aldehydes, alcohols,
esters, ketones, hydrocarbons and others. The most abundant compounds of P. eryngii dried by HPD, HAD and VMD were
all aldehydes, including isovaleraldehyde, caproaldehyde and 2-methyl butanal. However, alcohols were the major volatile
compounds including 1-octen-3-ol in the VFD-dried sample, which also contained esters, ketones, alkanes and pyrazines,
together with small amounts of other compounds. Among these drying methods, more volatile compounds with lower
thresholds were generated by heat treatment methods due to the interaction of compounds in the raw material. From these
findings, it was found that among the four drying methods, VFD could optimally maintain the quality of P. eryngii while
HPD method gave better results for its economic and stable characteristics.

Optimization of Neutral Protease-Assisted Extraction of Highland Barley Starch
ZHAO Yanqiao, ZHU Zhiyong, LI Jianying, ZHANG Lijun
2016, 37(4):  31-36.  doi:10.7506/spkx1002-6630-201604006
Asbtract ( 588 )   HTML ( 4)   PDF (2285KB) ( 196 )  
Related Articles | Metrics

The neutral protease-assisted extraction of highland barley starch was optimized using response surface
methodology. The effects of several operating parameters, namely solid to liquid ratio, enzyme dosage, hydrolysis time,
temperature and pH, on the residual protein content of highland barley starch were studied. Three main factors including
enzyme dosage, hydrolysis time and temperature were chosen to design response surface experiments using residual protein
content and starch yield as the responses. The results showed that the three selected factors as well as the interaction between
enzyme dosage and either hydrolysis time or temperature all had significant effects on residual protein content, but had no
significant effects on starch yield. The optimal extraction conditions in the selected experimental ranges were determined as
follows: enzyme dosage, 140.79 U/g; temperature, 45.01 ℃; and hydrolysis time, 2.57 h, leading to a starch yield of 60.36%
and a residual protein content of 1.31%.

Optimization of Preparation Process for Fat Substitute from Rice Bran Dietary Fiber by Response Surface Methodology
LIU Ying, SONG Dandan, FU Wei, YU Xiaohong, DOU Boxin
2016, 37(4):  37-43.  doi:10.7506/spkx1002-6630-201604007
Asbtract ( 524 )   HTML ( 3)   PDF (2873KB) ( 161 )  
Related Articles | Metrics

In this study, response surface methodology was used to optimize the preparation of fat substitute by
carboxymethyl substitution of rice bran dietary fiber. A Box-Behnken design involving the independent variables chosen
based on single factor experiments was used to define an experimental design matrix of reaction conditions for rice bran
dietary fiber. For the optimization of the independent variables, quadratic regression analysis was performed using Design-
Expert 8.0.6 software. The optimal parameters for the preparation of fat substitute were achieved as alkalization of rice bran
dietary fiber at 25.9 ℃ followed by 4.54 h etherification at 69 ℃ after addition of 16.27 g of chloroacetic acid per 15 g of
dietary fiber. Under these conditions, the degree of carboxymethyl substitution of rice bran dietary fiber was 1.266 8. IR
spectra confirmed the occurrence of carboxymethyl substitution in the fat substitute prepared rice bran dietary fiber.

Optimization of the Formulation of Konjac Glucomannan-Soybean Protein Isolate Mixed Gel by Response Surface Methodology
XU Xiaoping, ZHANG Yaning, FAN Qiao, CHEN Hourong, ZHANG Fusheng
2016, 37(4):  44-50.  doi:10.7506/spkx1002-6630-201604008
Asbtract ( 471 )   HTML ( 5)   PDF (2577KB) ( 288 )  
Related Articles | Metrics

This study aimed to enhance the compatibility of polysaccharide-protein mixtures, to improve their performance
and to study the effects of various factors on gelation and gel properties. The effects of formulation variables on gel strength
and water-holding capacity of konjac glucomannan (KGM)-soybean protein isolated (SPI) mixed gels were examined.
Optimization of formulation variables was carried out using combination of single factor method and response surface
methodology. A quadratic regression model was built using KGM to SPI ratio, total concentration, KCl concentration
and Ca(OH)2 dosage as the independent variables and gel strength as the response. Results showed that the optimum
conditions for preparing the mixed gel were determined as follows: mixed gel concentration, 4.5%; KGM/SPI ratio, 3:1;
KCl concentration, 0.13 mol/L; and Ca(OH)2 dosage, 0.15%. Under these conditions, the gel strength of SPI-KGM gels was
experimentally 2.758 N, approaching to the predicted value of 2.779 N. In addition, the texture properties of the mixed gels
were analyzed before and after the optimization, and the results indicated that the optimization was reliable.

ptimization of Multi-Enzymatic Extraction of Polyphenols from Granny Smith Apple and Their Antioxidant Activity
ZHANG Di1, LIU Yang1, LI Shuyi1,2,*
2016, 37(4):  51-57.  doi:10.7506/spkx1002-6630-201604009
Asbtract ( 660 )   HTML ( 4)   PDF (2702KB) ( 339 )  
Related Articles | Metrics

Granny Smith apple, an apple cultivar with high acidity, is rich in polyphenols, such as procyanidins. In this study,
the extraction of polyphenols from Granny Smith apple by multi-enzymatic hydrolysis was optimized by the combined use
of single factor method and Box-Behnken design. A mixture of cellulose and pectinase (2:1, m/m) was found to be the most
efficient enzyme for the extraction of polyphenols. The maximum yield of polyphenols of 5.07% was obtained when the
enzymatic extraction was done at 62.5 ℃ for 82.9 min with an initial pH of 3.7. According to the statistical analysis, the
response surface model developed could be used to analyze and predict the extraction of polyphenols from Granny Smith
apple effectively. Additionally, the polyphenols extracted from Granny Smith apple exhibited significant Fe3+ reducing
capacity and DPPH free radical scavenging activity and the half-inhibition concentration (IC50) for scavenging of DPPH free
radical was 22.72 μg/mL, showing that the extract is a good source of antioxidants, and could be further utilized and explored
as a useful food additive or antioxidant.

Optimization of Supercritical-CO2 Fluid Extraction of Essential oil from Panax ginseng Roots by Response Surface Methodology
CUI Lili, PANG Shifeng, LI Yali, ZHENG Peihe, ZHAO Hui, WANG Yingping
2016, 37(4):  58-61.  doi:10.7506/spkx1002-6630-201604010
Asbtract ( 668 )   HTML ( 3)   PDF (1836KB) ( 243 )  
Related Articles | Metrics

The supercritical-CO2 fluid extraction conditions of volatile oil from dried raw ginseng were optimized by
response surface methodology. Chemical constituents of the essential oil were analyzed by gas chromatography-mass
spectrometry (GC-MS) combined with automated mass spectral deconvolution and identification system (AMDIS) based
on retention index. The optimal extraction conditions were determined as follows: extraction pressure, 38 MPa; extraction
temperature, 55 ℃; static extraction time, 2 h and dynamic extraction, 1 h, under which, the maximum oil yield of 1.12%
was obtained. A total of 35 chromatographic peaks were separated from the essential oil of ginseng roots, 29 of which were
identified, accounting for 96.69% of the total peak area.

Optimization of Ultrasound-Assisted Papain Treatment for Tenderizatoin of Freshwater Mussel
ZHOU Dan1, WEN Liankui1, DONG Zhouyong2, ZHOU Yajun2,*
2016, 37(4):  62-67.  doi:10.7506/spkx1002-6630-201604011
Asbtract ( 488 )   HTML ( 5)   PDF (2480KB) ( 259 )  
Related Articles | Metrics

In order to improve the taste of freshwater mussel meat, tenderization was carried out by ultrasound-assisted
papain treatment. Using Box-Behnken experimental design, a quadratic regression model was developed indicating the effect
of ultrasonic power, ultrasonication time, and enzyme concentration on tenderization efficiency. Through response surface
analysis of the established model, the optimal parameters that provide the best tenderness of mussel meat were determined
as 6%, 150 W and 27 min for enzyme concentration, ultrasonic power and ultrasonication time, respectively. Compared with
individual treatment with papain, ultrasound and CaCl2, the combined treatment resulted in a 48% increase in soluble protein
content of mussel meat, with a simultaneous decrease in hardness and chewiness by 63% and 65%, respectively.

Effect of Homogenization on the Stability of Physalis pubescens L. Juice and Characterization of Its Particle Size and Morphology
XU Wei, WANG Guixin
2016, 37(4):  68-72.  doi:10.7506/spkx1002-6630-201604012
Asbtract ( 403 )   HTML ( 4)   PDF (2353KB) ( 289 )  
Related Articles | Metrics

The effect of high pressure homogenization on particle size distribution and stability of Physalis pubescens L.
juice was investigated. Based on juice stability coefficient and centrifugal sedimentation rate, the optimal homogenization
conditions were determined by combined use of single factor experiments and orthogonal array design as follows: pressure,
20 MPa; temperature, 45 ℃; and number of homogenizations, 2. Under these conditions, the stability coefficient of Physalis
pubescens L. juice was 0.798, and centrifugal sedimentation rate was 2.10%. The size distribution of all particles in the
intact juice was in the range of 0.260 1–4.96 μm, with an average of 4.561 μm, whereas the homogenized juice exhibited
two particle size ranges, 1.018–4.548 μm and 0.138 7–0.793 5 μm (accounting for 96.5% and 3.5% of total particles,
respectively), with an average of 1.963 μm. The particle morphology of the juice was observed by scanning electron
microscopy (SEM), and the cell debris was obviously increased and was found dispersed in the meantime.

Component Analysis
Determination of Four Active Compounds in Nightlily (Hemerocallis citrina) Flowers by High Performance Capillary Electrophoresis
GUO Fangfang, FENG Feng*, BAI Yunfeng, LIU Lizhen, CHEN Zezhong, ZHOU Jingqing, CAO Yudi
2016, 37(4):  73-76.  doi:10.7506/spkx1002-6630-201604013
Asbtract ( 445 )   HTML ( 2)   PDF (2041KB) ( 167 )  
Related Articles | Metrics

An efficient high performance capillary electrophoresis (HPCE) method was developed for the determination
of aloe-emodin, kaempferol, chlorogenic and quercetin in nightlily flowers (Hemerocallis citrina). Sample injection was
carried out by hydrodynamic injection for 5 s at 30 kV. The running buffer was 10 mmol/L Na2B4O7-H3BO3 (pH 9.15), and the
detection wavelength was set at 224 nm. Four target compounds were separated in 6 min. Under these optimal conditions, the linear
ranges for the above four compounds were 0.02–0.21, 0.01–0.90, 0.01–0.99, and 0.01–0.90 mg/mL with correlation coefficients
between 0.997 6 and 0.999 6, and the limits of detection were 2.45 × 10-5, 1.41 × 10-5, 1.78 × 10-5 and 8.63 × 10-6 mg/mL
(RSN = 3), respectively. The average recoveries were 97.5% to 101.2%, with a relative standard deviation (RSD) less than
4.76%. This method is fast, accurate and suitable for the detection of these active compounds in H. citrine flowers.

Amino Acid Composition and Nutritional Quality Evaluation of Wild Amygdalus pedunculatus Pall. Kernels from Different Growing Regions
JIANG Zhongmao1, WUYUN Tana2,*, WANG Sen1, ZHU Xuchun1
2016, 37(4):  77-82.  doi:10.7506/spkx1002-6630-201604014
Asbtract ( 596 )   HTML ( 2)   PDF (2237KB) ( 208 )  
Related Articles | Metrics

The amino acid composition and nutritional value of kernels of wild Amygdalus pedunculatus Pall. from 11
growing regions of Shaanxi and Inner Mongolia were analyzed using an automatic amino acid analyzer (model A300).
The results showed that the contents of total amino acids ranged from 21.74–32.35 mg/g with an average of 26.78 mg/g
in Amygdalus pedunculatus Pall. The proportion of essential amino acids to total amino acids ranged from 24.86% to
28.22%. The first limiting amino acid was Met and the score of ratio coefficient of amino acid (SRCAA) was averaged
at 69.13. The geographic origins were divided into 4 categories using the multivariate statistical method based on the
contents of total amino acids and essential amino acids. Among these geographic origins, Amygdalus pedunculatus Pall.
kernels from Xiaojinggou, Hohhot had the highest protein content and the best protein quality. Amygdalus pedunculatus
kernels contained plentiful amounts of taste-active amino acids and therapeutic amino acids, thereby having huge
potential for development and utilization.

Determination of Scopoletin in Noni Juice and Traditional Chinese Medicinal Compound Health Product Containing Noni Juice by HPLC
CHEN Chen, LIU Pinghuai, LUO Ning, LI Ang, HE Yifei, FU Jing
2016, 37(4):  83-87.  doi:10.7506/spkx1002-6630-201604015
Asbtract ( 686 )   HTML ( 8)   PDF (1910KB) ( 432 )  
Related Articles | Metrics

A high performance liquid chromatography (HPLC) method was established for the determination of scopoletin
in noni juice and a traditional Chinese medicinal compound health product containing noni juice. The chromatographic
separation was performed on an Elite SinoChrom ODS-BP column (4.6 mm × 200 mm, 5 μm) using acetonitrile-0.1%
phosphoric acid aqueous solution (30:70, V/V) as the mobile phase at a flow rate of 1 mL/min. The column temperature
was 25 ℃, and the detection wavelength was set at 348 nm. The results showed a good linear relationship between peak
area and scopoletin concentration in the range of 0.5–20 μg/mL. The average recoveries for noni juice and the health
product containing noni juice were 104.05% and 97.11%, with relative standard deviations (RSDs) of 0.81% and 1.99%,
respectively. This method proved to be accurate and reliable and could be used to qualitatively and quantitatively determine
scopoletin in noni juice and the compound health product containing noni juice.

Detection of Lactococcus lactis in Pickled Ma Bamboo Shoots by Quantitative Real-time PCR
XIA Xuejuan1, ZHENG Jiong1,2,*, YE Xiujuan1, WU Jinsong1, KAN Jianquan1,2
2016, 37(4):  88-92.  doi:10.7506/spkx1002-6630-201604016
Asbtract ( 431 )   HTML ( 4)   PDF (2060KB) ( 227 )  
Related Articles | Metrics

The dynamic changes of Lactococcus lactis in pickled Ma bamboo shoots with 6 g/100 mL salt concentration were
studied by quantitative real-time polymerase chain reaction (qRT-PCR). After the DNA extraction from standard Lactococcus
lactis, preparation of positive plasmids, protraction of standard curve, DNA extraction from samples at different fermentation
stages and qRT-PCR, and quantitative detection were performed. The results showed that during fermentation (0–63 days),
the concentration of Lactococcus lactis increased gradually from 2.41 × 102 copies/μL (day 0) to the maximum value of
4.63 × 108 copies/μL (day 14), an increase by six orders of magnitude, followed by a slow decrease to 5.02 × 106 copies/μL
at day 63. In conclusion, qRT-PCR technology provides a reliable, fast and effective way for the quantitative analysis of
bacteria in pickled Ma bamboo shoots.

Identification of Odor Changes in Yesso Scallop during Live Transportation by GC-MS
FU Runze1,2, SHEN Jian1, WANG Xichang2, LIU Junrong3, FAN Wen1,2, XU Wenqi1
2016, 37(4):  93-97.  doi:10.7506/spkx1002-6630-201604017
Asbtract ( 447 )   HTML ( 3)   PDF (2093KB) ( 170 )  
Related Articles | Metrics

Live transportation of Yesso scallop was simulated by a laboratory simulation platform, and gas chromatographymass
spectrometry (GC-MS) was used to quantitatively analyze volatile components of Yesso scallop during live
transportation. Principal component analysis and discriminant analysis were applied to identify changes in odor
characteristics of Yesso scallop during live transportation. The results showed that 57 volatile compounds were detected
throughout the transportation process, including sulfur compounds, alkanes, nitrogen compounds, heterocyclic compounds,
aromatic, alcohols nitrogen compounds and aldehydes. Sulfur compounds, nitrogen compounds and aldehydes could be
used as reference factors to evaluate the physiological status of Yesso scallop during live transportation. The whole live
transportation was divided into four stages including A (0 day), B (1st–3rd day), C (4th–6th day) and D (7th day). The four
volatile compounds hexane, chloroform, cyclohexene and decanal were identified as the most important factors to estimate
the transportation chain of scallops.

Comparison of Volatile Substances in Scallop Adductors and Skirts of Chlamys farreri
HUANG Zhongbai1, DING Yuan1, HUANG Jian2, ZHANG Dijun1, SUN Tingting1, HE Shan1, ZHOU Jun1, LI Ye1, ZHANG Chundan1, SU Xiurong1,*
2016, 37(4):  98-102.  doi:10.7506/spkx1002-6630-201604018
Asbtract ( 501 )   HTML ( 3)   PDF (1972KB) ( 146 )  
Related Articles | Metrics

Objective: To examine and compare changes of volatile substances in different parts of the scallop Chlamys
farrier with different heating temperatures and consequently provide a theoretical reference for Chlamys farrier processing.
Methods: The changes of volatile substances were detected and analyzed by electronic nose and headspace solid-phase micro
extraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS). Results: The electronic nose was sensitive enough
to detect the changes of odor characteristics during thermal processing. Odor of fresh scallop adductors and skirts changed
significantly when they were heated. A total of 16, 20, 7 and 18, 18, 20 volatile substances in scallop adductors and skirts,
respectively, were identified when fresh samples and those heated at 90 and 120 ℃ were detected by HS-SPME-GC-MS.
The major volatile compounds include alcohols, ketones, aldehydes, ester and hydrocarbon. Conclusion: There were 11, 12
and 6 common volatile substances in fresh samples and those heated at 90 and 120 ℃, respectively, and the contents of 13,
14 and 15 volatile substances varied between scallop adductors and skirts. Electronic nose combined with HS-SPME-GCMS
permits the analysis of the changes of volatile substance in scallop adductors and skirts at different heating temperatures.

Development of an Analytical Method for Nine Biogenic Amines in Chinese Yellow Wine by HPLC
CAO Lirui1, ZHU Song2, YU Jianshen3, XIA Yongjun1, WANG Guangqiang1, HU Jian3, AI Lianzhong1,*
2016, 37(4):  103-107.  doi:10.7506/spkx1002-6630-201604019
Asbtract ( 648 )   HTML ( 4)   PDF (1964KB) ( 343 )  
Related Articles | Metrics

An analytical method for biogenic amines in Chinese rice wine by reversed phase high-performance liquid
chromatography (RP-HPLC-HPLC) was developed. The biogenic amines in Chinese yellow wine were extracted with
trichloroacetic acid (TCA), and then pre-column derivatized with dansyl chloride for quantification using 1,7-diamino
heptane as the quantitative internal standard. A C18 chromatographic column (4.5 mm × 250 mm, 3.8 μm) was used
for separation. The mobile phase was composed of a mixture of acetonitrile and water at a flow rate of 1 mL/min, and
the ultraviolet (UV) detection wavelength was 254 nm. The results showed that nine biogenic amines (pyridoxamine
dihydrochloride, tryptamine, putrescine, cadaverine, beta phenethylamine, histamine, tyramine, spermine and spermine)
were separated completely within 40 minutes. In the concentration range of 1–50 mg/L, each biogenic amine presented good
linear correlation (R2 > 0.999). After the addition of a mixed standard solution of biogenic amines to Chinese yellow wine,
the recovery rates were 79.54%–89.55%, with relative standard deviations (RSDs) ranging from 3.14% to 6.35%, and the
limit of detection for each component was 0.002–0.009 mg/L. Therefore, The HPLC method with pre-column derivatization
and UV detection could be used for the determination of biogenic amines in Chinese yellow wine.

Comparative Analysis of Aroma Composition of Zhahaijiao, a Traditional Chinese Fermented Chili Product, during Fermentation by SDE and SPME Extraction
WANG Qiaobi, WANG Dan, ZHAO Qian, ZHOU Caiqiong
2016, 37(4):  108-114.  doi:10.7506/spkx1002-6630-201604020
Asbtract ( 642 )   HTML ( 2)   PDF (2050KB) ( 228 )  
Related Articles | Metrics

In order to establish the best extraction method for evaluating volatile aroma composition of Zhahaijiao, a
traditional Chinese fermented chili product, changes in the aroma compounds of the Zhahaijiao made with japonica rice
powder during fermentation were determined comparatively by solid phase micro extraction (SPME) and simultaneous
distillation extraction (SDE) combined with gas chromatography-mass spectrometry (GC-MS). Besides, changes in sensory
qualities were also evaluated. SPME could extract 76, 131 and 122 of volatile components from Zhahaijiao fermented for
0, 45 and 90 days, respectively, whereas SDE could extract 23, 42 and 82 of volatile components from the three samples,
respectively. With the extension of fermentation time, the contents of aroma components extracted by SDE increased
continuously while those obtained by SPME reached the highest level at 45 days and kept stable. Esters were the major
volatile components in the fermentation process. Totally 42–50 and 15–27 volatile esters with relative contents of 46.7%–
55.3% and 60.28%–67.28% were extracted from Zhahaijiao fermented for 45–90 days by SDE and SPME, respectively.
More alcohols (14–21 alcohols, accounting for 15.7%–22.6% of the total volatiles) and aldehydes (17 aldehydes, accounting
for 5.8%–12.3% of the total volatiles) could be detected from Zhahaijiao fermented for 45–90 days by SPME. Meanwhile,
more low-boiling-point and small-molecule compounds were extracted by SPME, while more high-boiling-point compounds
were obtained by SDE. The sensory evaluation showed that the 45-day fermented Zhahaijiao had a bright color, special sour
taste and mellow flavor. These results showed that SPME combined with SDE allowed more comprehensive and objective
evaluation of volatile aroma composition of Zhahaijiao and that the optimal fermentation time for Zhahaijiao made with
japonica rice powder was 45–90 days.

Flavor Quality of Rosa roxbughii Juice with Different Treatments for the Removal of Bitter and Astringent Tastes
ZHANG Yu, LUO Yu, LIU Fangshu, DING Zhuhong
2016, 37(4):  115-119.  doi:10.7506/spkx1002-6630-201604021
Asbtract ( 687 )   HTML ( 9)   PDF (2138KB) ( 288 )  
Related Articles | Metrics

Sensory evaluation combined with electronic tongue technique was used to study the influences of different
treatments for the removal of bitterness and astringency on flavor quality of Rosa roxbughii juice in order to select the optimal
treatment conditions. The results showed that sour, astringent and bitter tastes comprised the main flavor of Rosa roxbughii
juice. The combination of additives was obviously better than single additives for removal of bitterness and astringency. The
optimal combination found was as follows: 0.12% tannase and 0.015% ucralose. Under the optimized conditions, the sensory
evaluation score was the highest and the taste was appropriate with the lightest bitterness. The response values of C00 (bitterness)
and AE1 (astringency) were the lowest, as detected by electronic tongue. This study suggested that electronic tongue technique
combined with traditional sensory evaluation enables more accurate and reliable evaluation of food flavor.

Volatile Flavor Compounds of Chongqing Chengkou Bacon
CHANG Haijun, PENG Rong, TANG Chunhong
2016, 37(4):  120-126.  doi:10.7506/spkx1002-6630-201604022
Asbtract ( 470 )   HTML ( 4)   PDF (2055KB) ( 188 )  
Related Articles | Metrics

The volatile flavor compounds of bulk and vacuum packaged Chongqing Chengkou bacons produced in autumn
and winter, respectively, were extracted by solid-phase micro-extraction (SPME) and analyzed by gas chromatography
and mass-spectrometry (GC-MS). The results showed that in the same production season, the contents of esters, phenolics
and hydrocarbon of bacons with different packaging treatments changed obviously while the changes in aldehydes and alcohols
were not obvious. Under the same packaging treatment, the contents of phenols and hydrocarbon in bacons produced in different
seasons changed markedly but no significant changes in the contents of esters, aldehydes and alcohols were found. In addition, the
characteristic volatile flavor of bacon was mainly derived from phenols, alcohols and aldehydes, such as 3-methyl guaiacol, 4-methyl
guaiacol, guaiacol, 2,5-dimethylphenol, caproate, benzoic acid butyrate, ethyl caproate, and so on.

Se Contents and Dissolution Charateristics in Leaves of Ancient Fenghuang Dancong Tea Trees
WU Shuangtao1, ZHU Hui2,*
2016, 37(4):  127-131.  doi:10.7506/spkx1002-6630-201604023
Asbtract ( 477 )   HTML ( 10)   PDF (1876KB) ( 205 )  
Related Articles | Metrics

Tea-drinking is an ideal way to supplement the trace element selenium (Se) for people. Se contents in the
leaves of 10 cultivars of ancient tea trees for Fenghuang Dancong tea were measured by graphite digestion method, and
Se dissolution characteristics were analyzed during brewing. The results were obtained as follows: 1) the Se contents in
mature and young leaves were 0.056 0–0.352 5 and 0.045 5–0.299 0 mg/kg, with an average of 0.180 9 and 0.154 5 mg/kg,
respectively, showing a 17.46% difference between both leaves; 2) Se contents in the cultivars Songzhong Milanxiang
(0.299 0 mg/kg) and Songzhong Dongfanghong (0.210 2 mg/kg) met the requirement (0.2–4.0 mg/kg) of Se enriched Fenghuang
Dancong tea made from ‘one bud with two or three leaves’; 3) the leaves of Songzhong Milanxiang with the highest Se
content were selected as experimental materials for analyzing Se dissolution characteristics, and it was shown that 95–100 ℃
of brewing temperature and shorter than 5 min of brewing were fit for Fenghuang Dancong tea from the ancient tea tree,
and these tea leaves could be brewed for many times; and 4) the relationship between either brewing temperature, time or
number (x) and Se dissolubility (y) in tea infusion was consistent with linear equation (y = 0.000 4 x − 0.028 3, R2 = 0.939 8),
logarithmic equation (y = 0.006 6lnx + 0.001 1, R2 =0.957 9) and power function equation (y = 0.013 7 x− 0.786 6, R2 = 0.948 6),
respectively. The ancient tea trees for Fenghuang Dancong tea have great potential for the development of Se-enriched tea.

Comparative Evaluation of Chemical Methods for Analyzing Astringent Taste Compounds of Red Wine
MA Jing, YUAN Chunlong*, YANG Li, MA Tao, SU Pengfei, YAN Xiaoyu
2016, 37(4):  132-138.  doi:10.7506/spkx1002-6630-201604024
Asbtract ( 501 )   HTML ( 4)   PDF (2367KB) ( 279 )  
Related Articles | Metrics

A total of 24 red wine samples were analyzed by gelatin index, ovalbumin index, sodium dodecyl sulphate
polyacrylamide gel electrophoresis (SDS-PAGE), Folin-Ciocalteau, and protein precipitation methods, respectively. The
results obtained with these methods were compared with the perceived astringency. The protein precipitation assay showed a
strong correlation with the perceived astringency, which was convenient and suitable for extensive applications in wineries.

Simultaneous Quantification of 7 Components in Different Parts of Punica granatum Fruits Using Ultra-High Performance Liquid Chromatography-Triple Quadrupole Mass Spectrometry (UPLC-QQQMS)
WANG Changxi, YUE Lili, XU Haiyan, Uneer, HUANG Yan, ZHANG Haipeng, GAO Jie, MA Chaomei
2016, 37(4):  139-143.  doi:10.7506/spkx1002-6630-201604025
Asbtract ( 555 )   HTML ( 3)   PDF (1806KB) ( 198 )  
Related Articles | Metrics

An ultra-high performance liquid chromatography-triple quadrupole mass spectrometry (UPLC-QQQMS) method
was developed and validated to simultaneously determine seven constituents including chebumeinin A, chebumeinin B,
chebulic acid, pentagalloyl glucose, corilagin, chebulagic acid and gallic acid in dried whole pomegranate (containing
peels and seeds, a traditional Mongolian medicinal material), dried pomegranate peels (a traditional Chinese medicinal
material), and fresh pomegranate peels and seeds (Punica granatum L.). 4β-(L-acetylcysteinyl)-epicatechin was used
as an internal standard for the quantification. The internal standard was added to methanol before being used to extract
samples. The separation was performed on an Agilent ZORBAX Eclipse XDB-C18 column (2.1 mm × 50 mm, 1.8 μm) with
methanol-0.1% formic acid as the mobile phase at a flow rate of 0.4 mL/min. As a result, the linear ranges of chebumeinin
A, chebumeinin B, chebulic acid, pentagalloyl glucose, corilagin, chebulagic acid and gallic acid were 0.003 4–13.875 0,
0.013 5–13.875 0, 0.003 4–13.875 0, 0.216 8–55.500 0, 0.867 2–55.500 0, 0.216 8–55.500 0, and 0.003 4–13.875 0 μg/mL,
respectively, with correlation coefficients higher than 0.99. The average recovery rate of the developed method ranged
from 99.44% to 105.54% and the intra-day and inter-day relative standard deviations (RSDs) were 0.11%–0.95% and
0.14%–1.21%, respectively. This method is sensitive, simple, fast, and accurate, and can be used for the quality control of
pomegranate for medicinal use and related food products or pharmaceuticals.

Simultaneous Determination of 11 B Vitamins in Infant Formula by UPLC-MS/MS
CHEN Meijun1, WANG Min1, KANG Meijuan1, DUAN Qihui2, SHANG Jiaowen2, SHAN Yi1,*
2016, 37(4):  144-153.  doi:10.7506/spkx1002-6630-201604026
Asbtract ( 516 )   HTML ( 5)   PDF (3173KB) ( 534 )  
Related Articles | Metrics

Objective: To establish a method for the simultaneous determination of 11 B vitamins in infant formula by ultrapressure
liquidchromatography-tandem mass spectrometry (UPLC-MS/MS). Methods: The samples were dissolved in 0.1%
formic acid and then added with xinc acetate to precipitate the proteins. Then the filtrate was separated by an ACQUITY
UPLC HSS T3 column through gradient elution using 0.1% formic acid and acetonitrile as the mobile phase. Mass spectral
acquisition was done in the positive ion mode by applying multiple reaction monitoring and the analysis was completed
in 12 min. Results: High correlation coefficients (R2 > 0.99) for 11 B vitamins in their linear ranges were obtained. The
spiked recovery rates and accuracy (expressed as relative standard deviation, RSD) were determined to be in the ranges of
85%–110% and 1.03%–6.75%, respectively. The limits of quantitation (LOQs) for vitamin B1, vitamin B2, nicotinic acid,
niacinamide, pantothenic acid, pyridoxal, pyridoxine, pyridoxamine, folic acid, vitamin H and vitamin B12 were 40.0, 40.0,
30.0, 30.0, 50.0, 0.9, 1.2, 1.2, 2.0, 2.0, and 0.2 μg/100 g, respectively, an increase by 7.7% to 60% over those from the
national standards of China. Conclusions: The method is characterized by high sensitivity, simple operation, fast analysis and
short time. This method also has good precision and accuracy and can be applied to detect 11 B vitamins in infant formula.

Determination of the Protein Content of Milk by Digital Imaging Colorimetry
YUE Wei, LIU Le
2016, 37(4):  154-157.  doi:10.7506/spkx1002-6630-201604027
Asbtract ( 503 )   HTML ( 2)   PDF (2620KB) ( 209 )  
Related Articles | Metrics

The grey value obtained by digital imaging for the blue complex formed from the binding interaction of
Coomassie brilliant blue with proteins is positively linearly related to the concentration of proteins. Thus, a method was
established for the determination of the protein content of milk by digital imaging colorimetry. The imaging conditions,
color development conditions and interfering substances were investigated. The recovery rates for spiked milk samples were
between 97.5% and 102.6% with a relative standard deviation (RSD) less than 2%. Consistent results were obtained using
digital imaging colorimetry and spectrophotometry, but digital imaging colorimetry was more convenient and faster.

Comparison of Phenol-Sulfuric Acid and Anthrone-Sulfuric Methods for Determination of Polysaccharide in Green Tea
ZHANG Yuanyuan, ZHANG Bin
2016, 37(4):  158-163.  doi:10.7506/spkx1002-6630-201604028
Asbtract ( 1629 )   HTML ( 36)   PDF (2456KB) ( 1559 )  
Related Articles | Metrics

This study aimed to establish a phenol-sulfuric acid method for the determination of the polysaccharide content
in green tea and evaluate its performance in comparison with that of the anthrone-sulfuric method. In the phenol-sulfuric
acid method, three experimental conditions including phenol concentration, sulfuric acid dosage and color development time
were optimized by single factor experiments and response surface methodology using absorbance value as the dependent
variable. A mathematical regression model was established. The optimum experimental conditions were found as followes:
1 mL of 4.8% aqueous phenol solution, 5 mL of concentrated sulfuric acid, and detection at 488 nm after 29 min of color
development. There was a good linear relationship between absorbance and concentration in the range from 0 to 0.2 mg/mL.
The experimental results showed that the average recovery rate was equal to or higher than 97.55% with good reproducibility
(RSD = 1.82%, n = 7). The phenol-sulfuric acid method was rapid, accurate, sensitive and suitable for the determination of
polysaccharide in green tea.

Safety Detection
Detection of Genetically Modified Soybean by Helicase-Dependent Isothermal DNA Amplification Assay
ZHANG Jingjing1, WANG Zan1, ZHANG Cuixia1, MA Chaofeng1, ZHOU Wei1,2,*, ZHANG Yan1
2016, 37(4):  164-168.  doi:10.7506/spkx1002-6630-201604029
Asbtract ( 545 )   HTML ( 5)   PDF (1974KB) ( 265 )  
Related Articles | Metrics

Objective: To establish a new rapid method to detect genetically modified soybean based on helicase-dependent
isothermal DNA amplification (HDA). Methods: With four highly specific sets of primers synthesized to target genes
including Lectin in soybean and CaMV35S, NOS and CP4-EPSPS foreign genes, PCR reaction system was established. The
specificity and sensitivity of the PCR method were tested based on HDA and homology analysis was performed. Results: The
helicase-dependent isothermal DNA amplification method for the rapid detection of genetically modified soybean has been
established. The detection limits of CaMV35S, NOS and CP4-EPSPS genes in genetically modified soybeans by HDA were
all 0.2%. Conclusion: HDA is a rapid, user-friendly, specific and sensitive method for the detection of genetically modified
soybean, and is very suitable for use in grassroots laboratories with a broad prospect.

Classification of Different Origins of Maca Based on Infrared Spectroscopy in Combination with Statistical Analysis
WANG Yuanzhong, ZHAO Yanli, ZHANG Ji, JIN Hang
2016, 37(4):  169-175.  doi:10.7506/spkx1002-6630-201604030
Asbtract ( 525 )   HTML ( 2)   PDF (2375KB) ( 349 )  
Related Articles | Metrics

Based on Fourier transform infrared spectroscopy (FTIR), identification of the origin of 139 samples of maca
collected from Yunnan and Peru was conducted. The infrared spectra were preprocessed by multiple scattering correction
combined with second derivative and Norris smoothing. Through eliminating the noise spectral bands, the suitable number
of principal components was chose as eight. Based on the optimal number of principal components, by using interval partial
least squares (iPLS), the spectra in the range of 3 650.59–651.82 cm–1 was processed by optimization analysis. An iPLS-DA
classification model was built by screening the spectra of 98 samples in the ranges of 1 855.19–651.822, 3 054.69–2 756.78
and 3 650.59–3 353.6 cm–1. The R2, RMSEC and RMSEP of the model were 0.958 4, 0.785 8 and 1.164 2, respectively.
The verification with 41 samples indicated that the validation accuracy was consistent with that of the classification model
built using the original spectra, which was 87.80%. To further improve the accuracy of the classification model on the basis
of iPLS screening of spectral bands, the spectral information was optimized by genetic algorithm (GA) and shuffled frog
leaping algorithm (SFLA), respectively. The results showed that, through GA screening the frequency of spectral information
which was greater than 4 and 5, the filtered spectral data points were 62 and 29, respectively. Through SFLA screening the
probability of spectral information which was greater than 0.1 and 0.15, the filtered spectral data points were 77 and 27,
respectively. The validation results showed that the recognition efficiency of the classification model built by GA-PLS-DA
(62 data points) and GA-PLS-DA (29 data points) were 95.12% and 97.56%, respectively. The recognition efficiency of the
classification model built by SFLA-PLS-DA (77 data points) and SFLA-PLS-DA (27 data points) were 92.68% and 97.56%.
By comparing the above methods, we could find that the classification models built by iPLS-DA, GA-PLS-DA and SFLAPLS-
DA all had good prediction performance, of which the models built by GA-PLS-DA (29 data points) and SFLA-PLSDA
(27 data points) could more accurately identify the different origins of maca. The methods could provide a new way for
identification of the origin of maca with IR. The screening of the spectral variables could provide the basis for the difference
analysis of the chemical constitutes (components) in different origins of maca.

Detection of Virulence Genes of Four Escherichia coli O157:H7 Strains and Cold Stress Injury in the Bacteria
SHUI Xinyun1, WANG Huhu2, GAO Feng2, JIANG Yun1,*
2016, 37(4):  176-180.  doi:10.7506/spkx1002-6630-201604031
Asbtract ( 403 )   HTML ( 2)   PDF (1996KB) ( 228 )  
Related Articles | Metrics

In this study, the virulence genes of four Escherichia coli O157:H7 strains were detected by multiplex polymerase
chain reaction (PCR). Then three selective media were compared for enumeration of E. coli O157:H7 and the injury of
E. coli O157:H7 under cold stress was also investigated with the appropriate selective medium. The results showed that
CICC 21530 strain was positive for all the three genes stx1, stx2 and eae, while NCTC 12900 and one beef isolate were
eae-positive, and two other isolates were negative for all the three virulence genes, which indicated that the pathogenicity of
four strains was different. The counts of all four strains on three selective media were lower than those on tryptose soya agar (TSA)
(P < 0.05) but there was no significant difference between them except for cefixime-tellurite sorbitol macconkey agar (CT-SMAC),
which indicated that CT-SMAC was not suitable for counting E. coli O157:H7 due to the greater inhibition on normal bacteria,
while SMAC or mEMB could be used. Then the injury of E. coli O157:H7 stored at 4 ℃ (cold stress) was investigated with
each of these two selective media. The results showed that the counts on SMAC, mEMB, or TSA were decreased during
the whole storage and some bacteria were injured or killed on the 10th day. In the current study, the selective media for accurate
enumeration of four E. coli O157:H7 strains with different virulence genes were finalized, which would provide the scientific basis
for quantitative assessment and risk control of E. coli O157:H7 in food safety evaluation.

Rapid Detection of Caproic Acid and Acetic Acid in Liquor Base Based on Fourier Transform Near-Infrared Spectroscopy
LIU Jianxue, ZHANG Weiwei, HAN Sihai, LI Xuan, LI Peiyan, YANG Guodi, YANG Ying, XU Baocheng, LUO Denglin
2016, 37(4):  181-185.  doi:10.7506/spkx1002-6630-201604032
Asbtract ( 504 )   HTML ( 3)   PDF (2097KB) ( 619 )  
Related Articles | Metrics

Caproic acid and acetic acid, two important organic acids in liquor, have obvious effects on the quality of liquor.
In order to accurately and quickly measure the contents of caproic acid and acetic acid in liquor base, calibration models
were established based on Fourier-transform near-infrared spectroscopy with artificial neural network by cross-validation
after the original spectra were analyzed and interpreted. The results showed that the caproic and acetic acid in liquor
base exhibited strong near infrared absorption and that the best spectral pretreatment methods for the two acids were first
derivative combined with deduction of a straight line and standard normal variate (SNV) transformation, respectively. Based
on the selected spectral ranges of 6 101.7–5 446 cm-1, 11 998.9–7 501.7 cm-1, 6 101.7–5 449.8 cm-1, and 11 998.9–7 497.9 cm-1,
a calibration model was established using partial least square regression and the internal cross-validation method. After
optimization of the model, the correlation coefficients (R2) between the chemical values of caproic acid and acetic acid in
calibration samples and near infrared prediction were 99.73% and 97.00%, internal cross-validation root mean square deviation
were 0.90 and 0.63 mg/100 mL, and prediction standard deviation were 1.00 and 1.73 mg/100 mL, respectively. The method
has been applied with satisfactory results to quick determination of caproic acid and acetic acid in the distilled spirit industry.

Development of Target-Enriched Multiplex PCR Assay for Simultaneous Detection of Three Foodborne Pathogens
LIU Zhongmei1, XU Yigang1, QU Min2, MO Chunsheng2, LIU Xinliang1, LI Sulong1,*
2016, 37(4):  186-190.  doi:10.7506/spkx1002-6630-201604033
Asbtract ( 596 )   HTML ( 3)   PDF (2035KB) ( 317 )  
Related Articles | Metrics

In this study, a target-enriched multiplex PCR (Tem-PCR) assay for simultaneous detection of Salmonella,
Staphylococcus aureus and Shigella was developed. Based on the S. aureus femA gene, the Salmonella invA gene and
the Shigella ipaH gene, three pairs of specific primers together with a universal primer were designed. Following the
optimization of reaction conditions, the Tem-PCR assay was successfully established. Results showed that the Tem-
PCR assay was highly specific to the target bacteria with a sensitivity of 1.1 × 103 CFU/mL, 2 × 103 CFU/mL and
1.2 × 103 CFU/mL for Salmonella, S. aureus and Shigella, respectively. The Tem-PCR assay can effectively improve the
balance of amplification efficiencies of the primers employed in traditional multiplex PCR.

Investigation of Contamination Levels of Perfluorinated Compounds in Eggs from Nine Coastal Provinces of China
LIU Xiaowan1, ZHANG Hong2,*, LI Jing3, SHEN Jincan4, XIAO Chengui4, ZHAO Fengjua
2016, 37(4):  191-196.  doi:10.7506/spkx1002-6630-201604034
Asbtract ( 582 )   HTML ( 7)   PDF (1809KB) ( 240 )  
Related Articles | Metrics

This study aimed to examine the residue level and distribution of perfluorinated compounds (PFCs) in 1 060 egg
samples collected from nine coastal provinces of China. High performance liquid chromatography-tandem mass spectrometry
(HPLC-MS/MS) combined with dispersive solid phase extraction was applied in this research. The results indicated that
detection rate of PFCs in all the egg samples was lower than 50%, and 82% of ΣPFCs were medium- and short-chain PFCs.
Among all the egg samples, the highest ΣPFCs was detected in the samples from Jiangsu (1.24 μg/kg) whereas the lowest
ΣPFCs was detected in those from Zhejiang (0.124 μg/kg). Perfluorooctane sulfonate (PFOS) was the major perfluorinated
compound detected in the samples from Jiangsu while perfluoropentanoic acid (PFPeA) was the major perfluorinated
compound found to present in samples from other provinces, indicating that the residue of PFCs in eggs is correlated with
the environmental PFCs. The health risk assessment showed that the hazard ratios of PFOS, perfluoropentanoic acid (PFOA)
and other PFCs detected in eggs were all below one, inferring that the immediate harm via egg consumption is minimal.

Detection of Antiviral Drug Ribavirin in Laying Hens by Ultra High Performance Liquid  Chromatography-Tandem Mass Spectrometry
ZHENG Xin1, TANG Xiaoyan2,*, CAO Xingyuan3, QI Kai1, TAO Rui2, WANG Min2
2016, 37(4):  197-201.  doi:10.7506/spkx1002-6630-201604035
Asbtract ( 512 )   HTML ( 4)   PDF (1950KB) ( 240 )  
Related Articles | Metrics

This study aimed to examine the residues of the banned antiviral drug ribavirin in poultry. Eleven Jinghong laying
hens were fed with 30 mg/kg BW ribavirin via single oral administration and their blood samples were collected from a vein
under the wing at different time points. The ribavirin in the plasma samples was measured by using ultra high performance
liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) under the multiple reaction monitoring mode (MRM)
and quantified using isotope-labeled internal standard. The calibration curve for ribavirin exhibited good linearity over the
concentration range from 5 to 5 000 ng/mL, and the limit of detection (LOD) was 1 ng/mL. Average recoveries for ribavirin
spiked at 3 levels ranged from 86.4% to 97.1%, and the inter-batch and intra-batch relative standard deviations (RSDs) both
met the quantitative requirement. Ribavirin concentration in laying hens plasma increased rapidly after oral administration
but then decreased gradually with metabolic elimination. The results suggested that the pharmacokinetic characteristics of
ribavirin in hens include quick absorption, broad distribution, rapid elimination, and lower residue in tissue.

Determination of Diethylstilbestrol in Milk Using Dispersive Liquid-Liquid Microextraction Followed by HPLC
QI Qi, HUANG Min, XIE Haihua
2016, 37(4):  202-205.  doi:10.7506/spkx1002-6630-201604036
Asbtract ( 411 )   HTML ( 2)   PDF (2109KB) ( 180 )  
Related Articles | Metrics

A novel method for the determination of diethylstilbestrol in milk using dispersive liquid-liquid microextraction
coupled to high performance liquid chromatography (HPLC) was developed. Important parameters affecting extraction
efficiency, such as extraction solvent type and volume, anti-sticking agent type and volume, pH, salt concentration and
temperature, were discussed. Under the optimal conditions, the established method had high sensitivity, low detection limit
and high stability for the analysis of diethylstilbestrol. Ultrasound-assisted ionic-liquid cold-induced aggregation dispersive
liquid-liquid microextraction could be successfully used for the determination of diethylstilbestrol in milk.

A Method for Rapid Determination of Lutein and Its Stereoisomers
LI Dajing1,2, LIU Chunju1,2, XIAO Yadong1, PANG Huili1, LIU Chunquan1,2,*
2016, 37(4):  206-211.  doi:10.7506/spkx1002-6630-201604037
Asbtract ( 554 )   HTML ( 3)   PDF (2596KB) ( 199 )  
Related Articles | Metrics

This study aimed to establish a rapid method for the determination of lutein stereoisomers by high performance
liquid chromatography-diode array detection (HPLC-DAD) combined with atmospheric pressure chemical ionization mass
spectrometry (APCI-MS). Using a mobile phase composed of dichloromethane, acetonitrile and carbinol (20:30:50, V/V)
at a flow rate of 1.0 mL/min, lutein and its stereoisomers were separated effectively with good shape and without tailing
phenomenon. Lutein generated 15-, 13,13’- and 9,9’-mono-cis-lutein during thermal isomerization as identified based on the
maximum absorption wavelength, Q value, mass spectral characteristics and relevant literature data. Peak area and injection
amount of lutein showed a good linear relationship in the range of 4–260 ng. The recovery rate was higher than 95%, and
the relative standard deviations (RSDs) of both precision and stability were lower than 2%. The method has the advantage of
good separation, high accuracy and repeatability.

Determination of Total Sulfite in Xinjiang Specialty Raisin by Fluorescence Derivatization
WANG Jinxia1,2, LIN Jiangli1, LU Yi2,*, WANG Jide1
2016, 37(4):  212-215.  doi:10.7506/spkx1002-6630-201604038
Asbtract ( 566 )   HTML ( 3)   PDF (2221KB) ( 225 )  
Related Articles | Metrics

A rapid and accurate method for the determination of total sulfite in Xinjiang specialty raisin was developed using
fluorescence derivatization. N-(9-Acridinyl) maleimide (NAM) reacted with the sulfite in raisin to form strong fluorescent
derivatives, which were then detected by fluorometry. The linear range of the method was between 1.0 and 43.2 mg/L, with a
correlation coefficient (R2) of 0.999 3. At three spiked levels, the average recoveries of sulfite in raisin ranged from 92.2% to
100.2% with relative standard deviations lower than 3.80% (n = 3). Furthermore, the results obtained by this method for the
total sulfite content of raisin were consistent with those obtained by the pararosaniline method. These results indicate that the
fluorescence derivatization method can accurately and rapidly determine total sulfite in Xinjiang specialty raisin.

Survey and Analysis of Perfluorooctanoic Acid (PFOA) and Perfluorooctane Sulfonate (PFOS) Pollution in Livestock and Poultry Products from Jiangxi Province
WANG Donggen, YUAN Lijuan, ZHANG Li, ZHANG Dawen*, LUO Linguang, WEI Benhua
2016, 37(4):  216-221.  doi:10.7506/spkx1002-6630-201604039
Asbtract ( 500 )   HTML ( 2)   PDF (2200KB) ( 256 )  
Related Articles | Metrics

In order to clarify the pollution status of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS)
in livestock and poultry products from Jiangxi province, various tissues samples of farmed pigs, chickens, and ducks
(n = 260) were collected from livestock and poultry producing areas located in 5 cities in Jiangxi province, and PFOA and
PFOS concentrations in these samples were determined by using ultra performance liquid chromatography coupled to triple
quadrupole tandem mass spectrometry (UPLC-MS/MS). The highest mean concentration of PFOA was found in chicken
blood (0.52 ng/g wet weight (WW)), followed by pig liver (0.24 ng/g WW), chicken liver (0.14 ng/g WW), duck blood
(0.12 ng/g WW) and duck liver (0.029 ng/g WW). No PFOA was detected in pig blood, pork, chicken breast and duck
breast. However, PFOS was only detected in pig liver (0.20 ng/g WW). The results of health risk assessment showed that
there is little potential risk of exposure to PFOA and PFOS via the consumption of these products in Jiangxi province.

Double-Antibody Sandwich ELISA for the Detection of Transgenic Bar Gene Herbicide-Tolerant Soybean
LI Xiaoyu1, ZHANG Chunyu1, GUO Dongquan1, ZHANG Linlin2, YOU Qing3, DONG Yingshan1, WANG Yongzhi1,*, LI Qiyun1,*
2016, 37(4):  222-225.  doi:10.7506/spkx1002-6630-201604040
Asbtract ( 730 )   HTML ( 2)   PDF (1933KB) ( 292 )  
Related Articles | Metrics

To rapidly and efficiently detect transgenic Bar herbicide-tolerant soybeans, we produced a monoclonal antibody
and a polyclonal antibody against phosphinothricin acetyltransferase (PAT) protein encoded by the Bar gene and then
utilized them to established a double-antibody sandwich ELISA system for the detection of PAT protein, which could
quantify PAT in different tissues and materials from transgenic Bar herbicide-tolerant soybeans. Reaction conditions were
optimized as follows: 0.125 μg/mL capture antibody was coated onto the microtiter plates at 4 ℃ overnight after incubation
at 37 ℃ for 1 h, the antigen was incubated at 37 ℃ for 1.5 h, and the detection antibody at 6.25 μg/mL was incubated
at 37 ℃ for 1.5 h. The detection sensitivity was 0.04 ng/mL for purified PAT and 8 ng/mL for crude soybean protein.
The coefficient of variation of reproducibility was less than 3%. This method has been successfully applied to detect the
expression of PAT in the root, stem, leaf, flower and seed of transgenic soybean

Preparation and Characterization of Surface Molecularly Imprinted Polymers for Selective Adsorption of Ethopabate
ZHANG Lamei, LI Daomin*, LI Zhaozhou, LIU Erwei, LI Songbiao, CAO Li, GAO Hongli, WANG Fang, HOU Yuze
2016, 37(4):  226-232.  doi:10.7506/spkx1002-6630-201604041
Asbtract ( 439 )   HTML ( 8)   PDF (2404KB) ( 142 )  
Related Articles | Metrics

The novel functional monomer N,O-bismethacryloyl ethanolamine (NOBE) was synthesized and used to
prepare molecularly imprinted polymers (ETP-MIPs) for adsorbing ethopabate by surface molecular imprinting technique
using silica gel as the support matrix and ethylene glycol dimethacrylate (EGDMA) as the crosslinking agent. Three
polymerization conditions including molar ratio of template to functional monomer, molar ratio of template to crosslinking
agent and porogen type were optimized using an orthogonal array design. The type of porogen was the most important
factor, followed by the ratio of template to functional monomer and ratio of template to crosslinking agent. The best
imprinting efficiency was observed for molecularly imprinted polymers with a molar ratio of ETP to NOBE to EGDMA
of 1:2:20 using acetonitrile as the porogen. The Scatchard analysis indicated that there were two classes of binding sites in
ETP-MIPs; the equilibrium dissociation constant (Kd) and apparent maximum binding capacity (Qmax) for the high affinity
sites and low affinity sites were calculated as follows: Kd1=1.608 μg/mL, Qmax1=1.101 μg/mg; and Kd2=0.109 μg/mL,
Qmax2=0.172 μg/mg, respectively.

Contamination, Serotype, Drug Resistance and Pathogenicity of Streptococcus suis from Pork Samples in Chongqing
PENG Shaojing, DENG Huaying, ZHANG Yuanyuan, HU Shuyue, DING Lingling, LI Jixiang
2016, 37(4):  233-237.  doi:10.7506/spkx1002-6630-201604042
Asbtract ( 418 )   HTML ( 2)   PDF (1683KB) ( 153 )  
Related Articles | Metrics

A total of 132 strains of Streptococcus suis (S. suis) were isolated from 398 submaxillary lymphonodi samples
collected from pig slaughterhouses and 140 pork samples collected from farmers’ markets in Chongqing. The average
contamination rate of S. suis in the total samples was 24.5% (132/538). In addition, the S. suis contamination rates of
submaxillary lymphonodi and pork were 26.7% (106/398) and 18.6% (26/140), respectively. The serotype-specific PCR
assays were used to identify the serotypes and the detection rates of serotype 1, 2, 7, and 9 were 3.16% (17/538), 3.16%
(17/538), 6.88% (37/538) and 1.67% (9/538) in samples, respectively. The drug resistance of 18 isolates was evaluated
by K-B method. The results exhibited that these isolates were strongly tolerant to aminoglycosides, tetracyclines and
sulfonamides, but sensitive to penicillins and cephalosporins. Infection experiments in mice were conducted to determine the
virulence of 15 of the isolates. It was shown that these isolates were pathogenic differently to mice. The results of this study
indicated that much attention should be paid to multi-serotype S. suis contamination of pig carcass and pork in quarantine.

Determination of Imidacloprid and Acetamiprid in Tea by Gel Permeation ChromatographyUltra Performance Liquid Chromatography-Tandem Mass Spectrometry
DUAN Bing, HE Taixi, FAN Yuanyuan, ZHENG Bing
2016, 37(4):  238-241.  doi:10.7506/spkx1002-6630-201604043
Asbtract ( 557 )   HTML ( 3)   PDF (1920KB) ( 171 )  
Related Articles | Metrics

A method was developed for the determination of imidacloprid and acetamiprid residues in tea using gel
permeation chromatography (GPC)-ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS).
Tea samples were extracted with acetonitrile under ultrasonic irradiation and cleaned up with GPC. The elution fractions
at retention times between 10 and 17 min were collected for subsequent analysis. The portions collected from GPC were
blown to dryness under nitrogen gas stream and then the residue was re-dissolved with acetonitrile-0.1% formic acid. The
calibration curves developed were linear in the range of 0.5–100 μg/L with a correlation coefficient higher than 0.99. The
limits of detection (LODs) for imidacloprid and acetamiprid were 2.0 and 1.0 μg/kg, and the limits of quantification (LOQs)
were 5.0 and 3.0 μg/kg, respectively. The average recoveries of the method at three different spiked levels ranged from
76.94% to 91.68% for imidacloprid and acetamiprid with relative standard deviations (RSDs) from 2.67% to 7.90%.

Packaging & Storage
Effect of Walnut Green Husk Extract and Chitosan Mxitures on the Postharvest Quality of Muskmelon during Storage
WEI Jia, MA Xiaofen, ATAWULA·Tiemur, WANG Gangxia, WU Bin
2016, 37(4):  242-248.  doi:10.7506/spkx1002-6630-201604044
Asbtract ( 574 )   HTML ( 2)   PDF (2338KB) ( 221 )  
Related Articles | Metrics

In this study, the effect of walnut green husk extract and chitosan mixtures in three different proportions on the
postharvest quality and physiology of muskmelon from Xinjiang autonomous, China was analyzed. The results showed the
composite preservatives could decrease the decay index, weight loss rate and respiratory intensity of muskmelon, inhibit the
reductions in total soluble solid content and titratable acidity, and increase polyphenol oxidase (PPO) and peroxidase (POD)
activities during storage at 25 ℃ and 55%–60% relative humidity, while not significantly affecting fruits hardness. The
CHE-25 treatment with walnut green husk extract at high concentration showed better performance in terms of postharvest
quality and physiological factors, as well as enzyme activities. The CHE-25 could be the most suitable composite
preservative for muskmelon storage. Walnut green husk extract as a potential natural compound can be uesd to control the
postharvest quality of muskmelon.

Effect of Irradiation on Quality Characteristics of Stored Silkworm Chrysa
LU Chunxia, LIANG Guiqiu, LU Fei, DONG Guiqing, WU Jingjing, ZHOU Xiaoling, LI Quan, HUANG Zhengyong, LIN Gang
2016, 37(4):  249-254.  doi:10.7506/spkx1002-6630-201604045
Asbtract ( 504 )   HTML ( 2)   PDF (2187KB) ( 150 )  
Related Articles | Metrics

Samples of vacuum packaged silkworm chrysalis were irradiated using 60Co gamma ray at 0, 3, and 6 kGy and
stored at 4 ℃ for 60 days to explore changes in sensory indicators and quality of silkworm chrysalis with different gamma
irradiation doses and storage times (0, 30, and 60 days). The results showed that the chroma value, acidity value, fat content
and microbial quantity of silkworm chrysalis significantly decreased after irradiation, whereas the hardness, chewiness and
peroxide value significantly increased. No significant change in sensory evaluation, protein content or springiness was found.
The chroma value and microbial quantity decreased significantly with increasing irradiation dose during the entire storage
period, while hardness, chewiness, and fat increased. Peroxide value increased firstly and then decreased with increasing
irradiation dose. A lower increment in peroxide value was found when compared to the control. At higher irradiation dose,
peroxide value increased relatively slowly, but no significant change in the acidity value was seen. The sterilization effect of
6 kGy irradiation on silkworm chrysalis was better. It was concluded that irradiation could improve safely and effectively the
storage quality of silkworm chrysalis, resulting in prolonged preservation period.

Optimal Harvesting Time for Cold Storage of Newhall Navel Orange
ZHOU Liang1, YANG Wenxia1,2,*, DENG Lizhen1, LENG Feifan1, ZHONG Balian1,2
2016, 37(4):  255-259.  doi:10.7506/spkx1002-6630-201604046
Asbtract ( 419 )   HTML ( 3)   PDF (2147KB) ( 307 )  
Related Articles | Metrics

The effects of different harvesting times on postharvest quality, decay rate and chilling injury of Newhall navel
orange (Citrus sinensis Osbeck) during storage at low temperature were studied to determine the optimal harvesting time
for cold storage of navel orange. The contents of otal soluble solids (TSS), total sugar, titratable acid (TA) and vitamin C
(VC), total sugar/TA ratio, ,chilling injury index, weight loss rate and decay rate were determined. At the end of storage, an
increase in total sugar/TA ratio was observed in fruits from all harvesting times, whereas the contents of total sugar, TA and
VC decreased significantly at the same time. The content of TA decreased sharply and chilling injury index was higher in
fruits harvested in late October and early November, 2012. The quality of fruits harvested between late November and early
December was maintained well. Conversely, harvesting time had a clear influence on decay rate with 9.67% of decay in fruits
harvested at mid-December versus 0.67% in fruits harvested in late October. These results indicated that a period between
the mid-November and early December could be the optimal harvesting stage for cold storage of Newhall navel orange.

Preservative Screening for Prolonged Shelf Life of Fresh-Cut Grass Fish Belly during Cold Storage
HE Li, HOU Wenfu, AI Youwei
2016, 37(4):  260-265.  doi:10.7506/spkx1002-6630-201604047
Asbtract ( 589 )   HTML ( 3)   PDF (2253KB) ( 167 )  
Related Articles | Metrics

Out of 17 preservatives, previously found to be highly effective against Pseudomonas using a plate culture system, the
preservatives having little influence on the color, taste, morphology or elasticity of fresh grass carp belly were screened by sensory
evaluation. Results suggested that after treatment with gallic acid, citric acid, tannic acid, trimethyl phosphate, polylysine or phytic
acid, the color of fish belly remained normal, the flavor was maintained and no negative impact on morphology or elasticity was
seen. The quality change of grass carp belly with preservative treatments during cold storage was assessed. A first-order model
describing microbial growth was constructed based on the microbial growth curve. The bacteriostatic activity of preservatives was
quantitated by model parameters. This study showed that ε-polylysine was the best preservative for grass carp belly. It had less
impact on the quality of grass carp belly and exhibited stronger bacteriostatic activity than other preservatives. The shelf life of
fresh grass carp with ε-polylysine treatment and modified atmosphere packaging (50% CO2 + 50% N2) when stored at 4 ℃ was 13
days. In conclusion treatment with ε-polylysine can help maintain the shelf life of grass carp.

Effect of 6-Benzylaminopurine Treatment on Postharvest Quality and Reactive Oxygen Species Metabolism of Ipomoea aqua
LU Hang1,2, GAO Jianxiao1,2, HU Huali1, LI Pengxia1,*
2016, 37(4):  266-271.  doi:10.7506/spkx1002-6630-201604048
Asbtract ( 559 )   HTML ( 2)   PDF (2200KB) ( 121 )  
Related Articles | Metrics

Large-leafed Ipomoea aquatica was pretreated with 0 (as the control) and 30 mg/L 6-benzylaminopurine (6-BA),
and then stored at (10 ± 1) ℃ with 90%–95% relative humidity. Changes in the reactive oxygen species (ROS) metabolism
and quality of Ipomoea aquatica were assessed. The results showed that treatment with 30 mg/L 6-BA maintained higher
content of chlorophyll, increased the activity of superoxide dismutase, and decreased the activity of ascorbate peroxidase in
Ipomoea aquatica after 4 and 8 days of storage. However, no difference in peroxidase activity was observed between 6-BA
treatment and the control. Meanwhile, 6-BA treatment significantly delayed the decrease in endogenous antioxidants of
posthtarvest Ipomoea aquatica. For example, the decline in the contents of ascorbic acid and glutathione was slowed down.
Moreover, compared to the control sample, the increase in the production of superoxide anion radicals, and the contents of
hydrogen peroxide and malonaldehyde in 6-BA-treated samples were mitigated. These results suggested that 6-BA treatment
could alleviate the senescence of postharvest Ipomoea aquatica, thereby maintaining its quality.

Effects of Shading on Quality of “Cabernet Sauvignon” and “Cabernet Gernischt” during Veraison to Maturity Period
HANG Jie, JIANG Yumei*, LI Jixin, MI Lan, CHEN Yurong, HE Yingxia, ZHOU Anling, SHANG Le, HU Yanyun
2016, 37(4):  272-279.  doi:10.7506/spkx1002-6630-201604049
Asbtract ( 568 )   HTML ( 4)   PDF (2819KB) ( 187 )  
Related Articles | Metrics

The grape berries of two cultivars “Cabernet Sauvignon” and “Cabernet Gernischt” were shaded by bagging
during the period from veraison to maturity, and using those with conventional cultivation and management as controls, the
impacts of shading treatment on fruit quality and aroma compounds were examined. The results showed that shading resulted
in significant differences in quality and aroma versus controls. Compared to controls, hundred-berry weights of fully mature
“Cabernet Gernischt” and “Cabernet Sauvignon” with shading were increased by 7.43% and 8.74%, average particle sizes
by 1.57% and 2.60%, soluble solids by 7.50% and 2.76%, pH value by 4.16% and 1.04%, and titratable acid were decreased
by 25.37% and 14.71%, respectively. The analysis of aroma compounds showed that shading could inhibit the release of
alcohols, and enhance the release of aldehydes.