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Table of Content

25 February 2013, Volume 34 Issue 4
Influence of Milk on the Flavor of Soymilk/Milk mixture Fermented by Lactic Acid Bacteria
2013, 34(4):  1-5.  doi:10.7506/spkx1002-6630-20111126-277
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In order to investigate the main off-flavor compounds of fermented soymilk, headspace-solid phase microextraction (HS-SPME) combined with gas chromatograph-mass spectrometer (GC-MS) was used to identify the flavor compounds of fermented soymilk/milk mixture, and sensory evaluation was conducted for these fermented mixture samples. 44 flavor compounds were isolated and identified, 20 compounds in soymilk were determined identical to those in milk. aldehydes, alcohols and furans of fermented soymilk decreased with the increasing milk content, the off- flavor of fermented soymilk may come from aldehydes, alcohols and furans. As milk content increased, the concentrations of 21 compounds in fermented soymilk/milk mixture decreased. Through the analysis of flavor characteristics, threshold, relative content, trends, and sensory evaluation of fermented soymilk/milk mixture, the results showed that the most important compounds contributed to the off- flavor of fermented mixture were 1-octen-3-ol, hexanol, 2-heptenal and 2,4-decadienal.
Construction the Novel MWNTs/AChE Biosensor and its Application to Rapid Detection of Dimethoate
2013, 34(4):  6-10. 
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A novel amperometric biosensor for organophosphate pesticides based on multilayer films containing chitosan, multi-wall carbon nanotubes (MWNTs) and acetylcholinesterase (AChE) was developed. Micrographs of MWNTs/AChE multilayer films were obtained by scanning electron microscope, and properties of the resulting biosensors were measured by electrochemical measurements. Among the resulting biosensors, the biosensor based on five layers of multilayer films was best. Based on the inhibition of organophosphate pesticides on the AChE activity, using dimethoate as a model compound, the inhibition of dimethoate was proportional to its concentration ranging from 0.25 to 1.50 and from 1.75 to 10.00 μM, with a detection limit of 10 nM estimated at a signal-to-noise ratio of 3. The developed biosensor exhibited good reproducibility and acceptable stability, thus providing a new promising tool for analysis of enzyme inhibitors.
Optimization of Extraction Conditions for Flavonoids from Tenebrio molitor by Response Surface Methodology
Zhang Jian-xin
2013, 34(4):  11-16. 
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Objective: To obtain conditions for extracting flavonoids from Tenebrio molitor. Methods: Flavonoids was extracted from Tenebrio molitor with distilled water under the assistance of ultrasonic. On the basis of one-factor-at-a-time investigations, Box-Behnken experimental design was used to provide experimental data for establishing a regression model describing the yield of flavonoids, and response surface methodology was employed to analyze the pairwise interactive effects of liquid-to-solid ratio, extraction time, extraction temperature and ultrasonic power. Results: Liquid-to-solid ratio of 18.34:1(mL/g), extraction time of 30.06min, extraction temperature of 58.43℃, and ultrasonic power of 380.62W. Under the optimal extraction conditions, the actual yield of flavonoids was 11.47mg/g, which was in basic agreement with the theoretical value of 11.58mg/g. Conclusion: The optimization of the actual conditions and the theoretical prediction fitting degree is high.
Optimization of Phosphate Monoester of Canna edulis Ker Starch Based on Response Surface Methodology
2013, 34(4):  17-22. 
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Response surface methodology was employed to study linked phosphorous(LP) content of phosphate monoester of Canna edulis Ker starch by phosphorylation with monosodium orthophosphate and disodium hydrogen phosphate. The results showed that the molar ratio of NaH2PO4 to Na2HPO4, weight ratio of phosphate sodium to starch, reaction time and pH all had a marked effect on LP content, while the reaction temperature had a less significant effect. And the influence degree of those factors were as follows: molar ratio of NaH2PO4 to Na2HPO4﹥﹥reaction time﹥﹥pH﹥weight ratio of phosphate sodium to starch﹥reaction time. The optimal reaction conditions obtained were NaH2PO4 to Na2HPO4 molar ratio of 1:0.4, phosphate sodium to starch weight ratio of 1.66:1, reaction temperature of 139.86℃, reaction time of 2h and pH of 5.5. LP content experimentally obtained were 0.506%.
Optimization of blended beverage formulation containing lychee and apple juice by mixture design
2013, 34(4):  23-27. 
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The effect of different proportion of lychee and apple juice on the sensory properties of the blended beverages was investigated. The blended beverage formulations were prepared by using an extreme vertex design of mixture design and optimized with response surface methodology. The sensory properties including aroma, taste, color and overall acceptable for the blended beverages consisting of A (water, 70~90%), B (lychee juice, 5~15%) and C (apple juice, 5~15%) were evaluated by 5-point hedonic scale sensory evaluation. The results showed that an optimum formulation which contained 70% of water, 15% of lychee juice and 15% of apple juice had a good sensory values with 4.19, 3.92, 4.12 and 3.73 for aroma, taste, color, and overall acceptable respectively, and it is agreement with the predictive values.
Effect on Volatile Profiles of Rapeseeds by Hot-air Drying
2013, 34(4):  28-31. 
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This study was performed to evaluate the effect on volatile profiles of rapeseeds by hot-air drying. The rapeseeds were dried to final moisture content of 8% (wet basis) with different temperature, after which volatile profiles of rapeseeds were analyzed using HS-SPME/GC–MS method. The results were as follows: more than 85 kinds of substances were identified among the volatile profiles of rapeseeds, which were consisted of aldehydes, hydrocarbons, alcohols, esters, acids, phenols, ketones and ethers, with their relative content decreased successively. Among the volatile profiles, the esters, alcohols, olefin and possible glucosinolate decomposition products showed some disciplines with the change of drying temperature.
Extraction and Determination of Total Alkaloids from Fritillariae Bulbs by Response Surface Methodology
2013, 34(4):  32-36. 
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In order to achieve the optimal processing conditions of alkaloids from Fritillariae bulbs. Fritillaria cirrhosa was firstly investigated. Response surface design were used to explore the extractive rate of the alkaloids through changing solvent ratio (CHCl3:CH3OH), liquid volume and the extraction time. The content was determined by colorimetry. Results indicated that the optimal extractive conditions were solvent ratio (CHCl3:CH3OH) of 4.2:1, liquid volume of 30, and extaction of 4 h. The maximum total alkaloids of 5.379 mg/g was from Fritillaria hupehensis under the optimal extractive conditions. This method is reliable, easy to operate. The optimized extractive conditions of should be the best for the extraction of the Fritillaria bulbs.
Optimizing the process conditions for lutein extraction from corn protein powder by Supercritical CO2
2013, 34(4):  37-41. 
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This paper in order to obtain high purity lutein, with corn protein powder as raw materials,to study the extraction process conditions for lutein by supercritical CO2,taking the HPLC as the determination method. The technology parameter of lutein extraction was studied by response surface analytic.Based on the single factor experiment,selecting extraction time,temperature and pressure three main factors,with the purity of lutein as response value to optimize the extraction process parameters and gain the optimum extraction process conditions:extraction time is 2.3h,temperature is 42℃,pressure is 30 MPa,φ(ethanol)=90% as the entrainer and the additive amount is 5%,by which the lutein purity is 46.8% at these conditions and the verification is 46.5%.
The research of the extracting, purification and the hypoglycemic effect of Lycium chinense. leaf polycose
2013, 34(4):  42-46. 
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Response surface methodology (RSM) was applied to optimize the best extracting method of Lycium chinense. leaf. Model equation was proposed with regard to the effect of the ratio of Lycium chinense. leaf powder to water , temperature and time. The optimum conditions for the effect of the ratio of Lycium chinense. leaf powder to water , temperature and time obtained using RSM with regard to the content of polycose were 1:47, 72.9℃, and 2 h 12min respectively. The crude polycose was then purified by D 101 macroporous resin and DEAE-52 column. Phenol-sulfuric acid method was chosen to test the purity of sample which was up to 92.5%. The anti-diabetic activity of the polycose was assessed using enzymatic inhibitory assays against the α-glycosidase. The percentage of the inhibition of U/mL α-glycosidase is 93.7% however the percentage of the inhibition of control acarbose was only 21.7%.
Studies on the Glutaminase Modification Process of Rice Glutelin
2013, 34(4):  47-50. 
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Glutaminase modification process of rice glutelin was studied. The influences of the ratio of glutaminase to protein, reaction temperature and pH to deamidated process were studied, using deamidation degree (DD) and solubility as indexes. The process conditions were optimized by Orthogonal on the base of the results of single factor test. The results showed that the optimal conditions were as follows: the ratio of glutaminase to protein of 1:7, 37℃, pH7.0. At the optimal conditions, the DD reached to 52.76%, and solubility of modified rice glutelin was 93.78%.
Study on the ultra-filtration process of polysaccharides from Stachys floridana Schuttl. ex Benth
2013, 34(4):  51-54. 
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Firstly, the effects of operation pressure, temperature and pH value on the ultra-filtration of polysaccharide from Stachys floridana Schuttl. ex Benth (SFPS) were investigated. Then, a multi-factor orthogonal experiment design was conducted to optimize the conditions of ultra-filtration based on the results of the single factor experiment. Finally, the optimal method for cleaning the membrane was determined by evaluating the membrane flux of water before and after the clean of membrane. As results, it was determined that ultra-filtration was better than conventional method for the concentration of SFPS, and the optimal conditions were determined as following: operation pressure 0.35 Mp, temperature 30 ℃, and pH value 6.5. The suitable method for the clean of membrane was washing the membrane with pH 8.5 NaOH solution at 40 ℃ for 0.5 h.
Separation and Purification of Galangin from Alpinia officinarum Hance by Counter-Current Chromatography combined with Silica Gel Chromatography
2013, 34(4):  55-58. 
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Purpose: To establish a method for the separation and preparation of galangin from Alpinia officinarum Hance. Methods: Two methods were developed for the preparative separation of galangin from Alpinia officinarum Hance, counter-current chromatography (CCC) directly and counter-current chromatography (CCC) combined with silica gel column chromatography. Results: The crude extract was pre-separated by silica gel chromatography, then separated by CCC with a two-phase solvent system composed of petroleum ether-ethyl acetate-ethanol-water (2:0.4:0.8:0.9, v/v) and high purity of galangin was obtained. 15.6mg galangin with the purity of 99.1% and 5.2mg unknown compound Ⅱ with the purity of 95.2% were obtained. Conclusions: The result indicates that silica gel chromatography combined with counter-current chromatography(CCC) can separate and preparate high purity of galangin from Alpinia officinarum Hance. This method has practical value and provides theoretical foundation for the further development.The method can be used for the preparation of the relevant standard materials and the development of functional factors.
Optimization of Extraction Technology of Polyphenols from Blueberry Leaves By Response Surface Method
2013, 34(4):  59-64. 
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Abstract: The polyphenols was extracted with ethanol from blueberry leaves. According to the experiments of single factors, Plackett Burman design was applied to study the factors of extraction and it was found that ethanol concentration (p=0.0025), extraction temperature (p=0.0091), solid-liquid ratio (p=0.0236) were the key factors to the extraction. It was optimized on the extraction of polyphenols from blueberry leaves by response surface method. A quadratic equation model for phenolics extraction was set up and the effects of the few factors and their corresponding relationships was obtained. The optimal extraction conditions was as follows: ethanol concentration 62.05%, extraction temperature 67.54℃, solid-liquid ratio 1:23.65, extraction time 2.06h. Under the optimized condition, the extraction yield was 91,02%. The model played an important role in predicting the extraction of polyphenols from blueberry leaves.
Extraction Technology of Main Bio-active Substances from Cinnamonmum burmannii Fruit
ZHANG Jing
2013, 34(4):  65-70. 
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Anthocyanins, proanthocyanidins and pectin are main bio-active substances in C. burmannii fruit. The research objective of the extraction technology of the cubstances from the fruit was to provide a technical basis for its comprehensive utilization. The results conducted by single factors and orthogonal experiments with water used as solvent and 5W/mL ultrasonic treatment indicated that the optimum conditions are as follows: the pH=1, the soaking 60min at 50℃, the ratio of liquid to solid 13:1 and the ultrasonic time 90s. The extraction rates of anthocyanins, proanthocyanidins and pectin after 2 times of extraction were 92.55%, 95.65% and 96.51% respectively. After mixing the extract liquid and DM301 resin, with the proportion of 40:1 and statically absorbed, the absorptive rate of anthocyanins and procyanidins were 94.58% and 96.63%. The desorption rate of anthocyanins and procyanidins were 96.47% and 94.66% respectively. Anthocyanins and proanthocyanidins on DM301 were dynamically eluted with 80% aqueous ethanol solution at 1BV/h flow rate, and their desorption rates in the eluant of 40% the resin bed volume were 92.23% and 93.11% respectively. The research results suggested that it is a cost effective method to extract the bio-active substances from C. burmannii fruit with water, ultrasonic treatment and resin separation.
Generation and Control of Benzo (a) pyrene in Oil-tea camellia seed oil
2013, 34(4):  71-74. 
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The causes of generating Benzo (a) pyrene in Oil-tea camellia seed oil was studied by researching production technics (hot pressing,cold pressing,solvent extraction and refining processes) .The results was shown as follows. The Benzo (a) pyrene content of cold pressing oil is (2.56±0.0804)μg/kg,which can meet the safety demand (≤10μg/kg)without refining . The major cause of excessive Benzo (a) pyrene content in the oil extracted by traditional processes is high temperature, rather than solvent. Neutralization and deodoring at high temperature may lead to obvious increase(about 84%~247%), whereas bleaching and winterization may lead to lot of reduce in the Benzo (a) pyrene content(about 71.5%~85.9%). Therefore, in the producing of Oil-tea camellia seed oil, the high temperature condition should be avoiled, the bleaching and winterization process must be used, whereas the technology parameter of neutralization and deodoring must be controled, so that the oil was moderately refined in order to obtain safety edible oil.
Optimization of cellulase enzymolysis on extraction by response surface methodolog
Shi-Quan QIAN
2013, 34(4):  75-79. 
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To discuss the impact of cellulase on extraction of resveratrol,response surface methodology(RSM) was investigated with the content of resveratrol as the response value and cellulase dosage, enzymolysis time and enzymolysis temperature as indepengdent variables, on basis of single factor experimengts,.The results showed that cellulase dosage had a extremely significant effect on the yield of resveratrol, but enzymolysis time and enzymolysis temperature had no significant effect. The effects order of three factors on content of resveratrol were as follows: cellulase dosage first, enzymolysis time second, and then enzymolysis temperature. The optimum enzymolysis conditions were dosage of cellulase 1.30%, time of enzymolysis 1.48h and temperature of enzymolysis 55.49℃. Under optimal conditions, the content of resveratrol was finally determined to be 0.746 mg.g-1, which was 1.15 times of that of non-optimization.
Study on preparation of flaxseed oil microcapsule using flaxseed gum as wall material
2013, 34(4):  80-82. 
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Flaxseed oil was microencapsulated with the spray drying method using flaxseed gum as wall material. The effect factors of preparing flaxseed oil microcapsule had been investigated in detail according to microencapsulation efficiency and the ratio of oil content. The results showed that the optimal spray drying processing conditions were determined as follows, the air temperature at the inlet was 170 ℃, and at the exit was 70 ℃, the rotating speed of centrifugal atomizer was 24000r/min, and liquid feed rate was 50.41mL/min. The content of microencapsulation efficiency was 95.32% and the ratio of oil content was 59.48%.
Synthesis of L-Menthyl β-D-Lactoside
2013, 34(4):  83-87. 
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In order to improve the thermostability and water solubility for L-menthol, its molecular structure was modified as a glycosidation derivative. With L-menthol and α-lactose as raw materials, a target compound L-menthyl β-D-Lactoside (4) was synthesized by three-step of acetylation, coupling, and deprotection, the total yield was 42.3%. The intermediate product and target compound were analyzed by melting point, optical rotation, NMR and MS technology. The results have showed that the compound 4 has desirable thermostability and excellent water solubility.
Optimozation of Extraction Techenology of Flavonoids from Black Beauty potato and Evaluation of Antioxidant Activities
2013, 34(4):  88-93. 
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Abstract: The aim of this study was to investigate optimum condition for extraction of flavonoids and the antioxidant activities from the Black Beauty potato. The results showed that extraction rate of the flavonoids from Black Beauty potato is affected in turn temperature, solid to liquid ratio and the concentration of ethanol .The optimum conditions of flavonoids extraction were temperature78℃, 62% ethanol, solid to liquid ratio 1g:35mL.Under the optimal conditions,the maximum response value yield (1.037%) was consistent with the experimental value (1.025%) ,indication the feasibility and validity of response surface methodology in optimizing the extraction of flavonoid from the Black Beauty potato. Black beauty potatoes flavonoids compared with VC and rutin , the ability of scavenging DPPH free radical was flavonoids>VC>rutin, When the concentration of flavonoids solution was less than 20μg/mL, ability of scavenging ABTS free radical and antioxidant were higher than VC, but always greater than rutin.The results indicated that the flanonoids have significant antioxidant activities,which can be used as a source of potential antioxidant or function food material.

Study on Extraction Technology of total flavonoids from the Artemisia selengensis Turcz by Response Surface Method
2013, 34(4):  94-98. 
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Studies were made on extracting total flavonoids from Artemisia selengensis Turcz in this paper. Based on singer factor test, response surface method was used to study effects of extraction temperature, ethanol concentration, solid-liquid ratio and extraction time on extraction rate of total flavonoids from Artemisia selengensis Turcz, and a second order quadratic equation for total flavonoids extraction was finally obtained. The results showed that the model was of great difference, and total flavonoids from Artemisia selengensis Turcz was analyzed and predicted by the model. factors influencing the extraction of total flavonoids from the Artemisia selengensis Turcz by the water bath method were in the order as follows: extraction time>ethanol concentration>solid/liquid ratio(g/mL)>extraction temperature. the optimum extraction conditions of total flavonoids from Artemisia selengensis Turcz were ethanol concentration 70%, extraction temperature 80℃, solid/liquid ratio(g/mL) 1:100, extraction time 180 minutes, the extraction rate of total flavonoids from Artemisia selengensis Turcz was 6.58% under the optimal conditions.
Double-layer Embedment Process and Application of Lactobacillus Acidophilus Microcapsule
2013, 34(4):  99-103. 
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To insure Lactobacillus acidophilus against mechanical compression and gastric acid, successfully reach the intestine to act the role of probiotic.,this paper adopted porous starch as wall material to microencapsulate Lactobacillus acidophilus. Through the single factor experiment and orthogonal experiment, four factors that influenced microencapsulation such as pH value, oscillation time, porous starch dosage and temperature had been analysised. The results show that: the porous starch dosage of 5 g, pH 6.0, temperature 20 ℃, concussion 200 r/min 50 min, the embedding rate is 67.12 %.This is the optimum technological conditions of Lactobacillus acidophilus microencapsulation. According to detecting the change of Bifidobacterium, Lactobacillus, Escherichia coli, Clostridium perfringens in quantity and pH value of canine fecal, which is obtained from puppies after fed the preparation of microencapsulation of Lactobacillus acidophilus, which can effectively improve the dog gut microflora.
Effects of Process Condition on Ripening and Quality of Ultrafiltration Cheddar Cheese
2013, 34(4):  104-108. 
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Cheese were made with ultrafiltrated and microfiltrated milk. The influence of different heating time, mature temperature on the composition, proteolysis and texture of cheddar cheese were studied. The results show that yield increased due to the extended heating time. By measuring the pH 4.6 SN and 12% TCA soluble nitrogen, the proteolysis of the cheeses with elevating maturation temperature could accelerate. The texture was determined by TA-XT2.The differences of flexibility, cohesion, viscosity of ultrafiltrated milk cheese were not significant comparing with the control cheese. Flexibility of cheese texture, cohesion, viscosity are reduced and the difference was significant (P <0.05) while raising the ripening temperature, which was related to protein degree of hydrolysis under the same conditions. Combined with sensory evaluation, the cheese with higher ripening temperature have low flavor score due to bitter taste; meanwhile, the overall score of texture were lower possibly because lower hardness, poor chewiness.
RSM of Optimized Cellulase Extraction of polyphenol from Carga cathayensis Sarg peels
2013, 34(4):  109-114. 
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Response surface methodology was employed to optimize the extraction condition of polyphenols from carga cathayensis sarg peels treated with cellulase. On the basis of one-factor-at-a-time experiments, a four-factor, three-level quadratic general rotary unitization design was employed to establish a quadratic polynomial mathematical model that describes extracting rate as a function of four process conditions, and the established model was analyzed by drawing response surface and contour plots. The optimal extraction conditions were determined as follows: 4U/g substrate at pH 6 and 70℃ for 70min. Under these conditions, the extracting rate of carga cathayensis sarg peels was predicted to 63.43% and observed to 61.72% with a relative error of 2.77%.

Optimization of Extraction Technique of Polysaccharides from Phellinus igniarius Fermentation Liquor by Response Surface Methodology
2013, 34(4):  114-117. 
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Optimal processing parameters for extraction of Phellinus igniarius polysaccharides in fermentation liquor with the content of polysaccharides as index were determined. On the basis of single factor experiments, the method of response surface method(RSM) for optimal parameters was adopted. Finally,The results of the study shows the optimal extraction process was obtained as follows: extraction pH12, extraction temperature 96℃, extraction time 1.6h. Under these conditions,the content of Phellinus igniarius polysaccharides reached 11.67mg/ml. The model turned out to be with good fitting degree and good feasibility.

Application of HS-SPME and GC-MS analysis of trace volatile components in the liquor fermented grains
2013, 34(4):  118-124. 
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Application HS-SPME and GC-MS method extraction the volatile components of the solid phase micro of the Chinese white wine fermented grains. Different types of SPME fibers, the water bath temperature, ultrasonic extraction time, and sample extraction on the extraction efficiency of trace volatile components. The results showed that the optimum condition for 65μm the PDMS / DVB SPME fibers, water bath temperature is 60℃, extraction without ultrasonic and the amount of fermented grains powder 10g. Throughout the fermentation process, this method detected 105 kinds of trace volatile components from fermented grains ,and we get the variation of the number and relative content of volatile substances species over time.

Study on Determination of Triglyceride Content by Thin Layer Chromatograph
2013, 34(4):  125-128. 
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Used the internal standard method to quantitative analysis of triglyceride content in mixed glycerides, applying the triglyceride separated from mixed glycerides by Silica gel column chromatography to obtain the high-purity products of triglyceride, which is to be the triglyceride standard. Mixed glycerides separated by TLC, eluted and colored, and then showing photometric values by spectrophotometry at 700±1nm wavelength instruct the content of triglyceride. The average recovery was 99.8%. This method was specific accurate, but precision slightly lower. Study on obtain the high-purity triglyceride standard, which showed a good linear relationship within the range of 10-100μ g/ml. Under insuring about 5 min coloring time conditions, detection results were stability in 1.5h. The limits of detection for the method valued were 0.55 μ g/ml, quantitative detection lower limit of 1.83μ g/ml. This method provides a simple and quick way to determinate of triglyceride content in the mixed fatty acid, through several experiments can reduce the random errors and improve precision.
Simultaneous Determination of 27 kinds of food additives and illegal additives in vegetable oil and seasoning oil by High-Performance Liquid Chromatography- Tandem Mass Spectrometry
2013, 34(4):  129-134. 
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A high performance liquid chromatography- tandem mass spectrometry(HPLC- MS/MS)method for determination of 18 kinds of food additives and 9 kinds of illegal additives in vegetable oil and seasoning oil has been developed. Samples were diluted by hexane, extracted by acetonitrile and the acetonitrile layer was made up to constant volume before tested the 18 kinds of food additives. Hexane layer was concentrated before it cleansing through GPC, and the eluent was concentrated, made up to constant volume, at last the treated samples used HPLC-MS/MS assay. In the electrospray ion mode and MRM mode,27 kinds of compounds in the range show a good linear relationship, linear coefficients were greater than 0.983. The average recoveries ranged from 78.2% to 108.3%, the relative standard deviation is within0.9%-17.7%.This method can be used for testing the food additives and illegal additives in vegetable oil and seasoning oil. Applied this method in market samples detection,we found TBHQ in five kinds of samples,but,all of them was below the maximum limit in China.

Key aroma compounds of Yanghe supple and mellow aroma style liquors
2013, 34(4):  135-139. 
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The total of 66 aroma compounds were determined by headspace solid-phase microextraction followed by GC-MS on the basis of micro volatile compounds and aroma compounds of Yanghe supple and mellow aroma type liquors. Ethyl hexanoate is the key aroma of supple and mellow aroma style liquors by calculation of odor activity values (OAVs) of aroma compounds; OAV is more than 27000, and average OAV of 4 samples is 24799. Ethyl 2-methylbutanoate, dimethyl trisulfide, ethyl pentanoate, ethyl butanoate, and ethyl octanoate are important aroma compounds. Pentanoic acid, ethyl 2-methylpropanoate, 3-methylbutanal, ethyl 3-methylbutanoate, and hexanoic acid contribute to aroma and flavor of Yanghe liquors. The results showed the key aroma compound of supple and mellow aroma type liquor was same to strong aroma type liquor, whereas the important aromas were different.

Changes in the Concentration and Composition of Volatile Organic Sulfur Compounds (VOSCs) during the Decay of Navel Oranges
2013, 34(4):  140-143. 
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The components, concentrations and compositions of volatile organic sulfur compounds (VOSCs) emitted from Newhall navel orange (Citrus sinensis L. Osbeck) were investigated during the laboratory-incubated decay under uncontrolled conditions for a period of one month, using preconcentrator coupled with gas chromatography-mass spectrum (GC-MS). In total, three VOSCs including dimethyl sulfide (DMS), carbon disulfur (CS2) and dimethyl disulfide (DMDS) were determined in the gases released from fresh and decaying navel oranges. For total volatile organic sulfur compounds (TVOSCs) or individual VOSCs, their concentrations were very low when naval oranges fresh, and increased with decay time to attain the maximum and then decreased to be very low and steady until the end of the experiment. CS2 dominated in VOSCs released from navel oranges when fresh and in the early 2 day of incubation, while DMS was the most abundant VOSCs after 2 days of incubation.

Effects of Bagging on Lemon Aroma Components
Chao-Fei HE Bining Jiao
2013, 34(4):  144-159. 
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The aroma components of bagged or non-bagged Anyue lemons, including their peels and pulps, were detected and analyzed by solid phase microextraction (SPME) coupled with gas chromatography-mass spectrometry (GC-MS). Simultaneously, the effect of bagging technology were analysed on the aroma components. Components semi-quantitative evaluation was carried out by comparing peak area of each compound with that of the internal standard. The results showed that volatile compounds mainly were consisted of hydrocarbons, alcohols, aldehydes, esters and ketones in a mass to little of sequence. The aroma components in peel always were more abundant than in pulp whether been bagged or not. Aroma quality of lemon was mainly reflected in peel. Compared with non-bagged lemons (CK), the types of the majority volatile compounds would be hardly changed, and the relative contents of oxygenated compounds were reduced after bagged, whose decrement was under 2.91%. So bagging would lower the aroma quality of lemon, but not serious. The tow isomers and points of Citral, whose relative amounts possess a conclusive lemon odor, had stable mass ratios of neral and geranial, which are about 2-3 in peel and 1-2 in pulp.

The fast qualitative analysis and accurate quantitative analysis of neotame in wine by high performance liquid chromatography method
2013, 34(4):  154-156. 
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A high performance liquid chromatography (HPLC) method for the fast qualitative analysis and accurate quantitative analysis of the artificial sweetener neotame in wines was developed. Neotame was fast qualitative analysis on a Waters Nova-Pak C18 column with an ultraviolet detector at 218 nm using acetonitrile: ion-pair reagent=40:60 (V/V) as mobile phase, and the retention time of neotame was about 13.4 min. The contents of neotame in the suspected samples were determined under gradient elution condition, and the retention time of neotame was about 15.9 min. The detection limit of the developed method was 0.37 μg/mL, and the mean spike recoveries for neotame in a blank wine sample were between 99%~101% , with a relative standard deviation below 1.0% (n=5). The method proved to be simple, accurate and practical, and it can save 50% time in analysis of large quantities of samples.

Analysis of Dominating Microbial Species in Cantonese Sausage by the Culture-independent and PCR-DGGE Methods
2013, 34(4):  157-160. 
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In order to analysis bacteria community structure overally and systematically in Cantonese Sausage, and to find out the dominating microbial species, which provided a basis for the research of culture starter.The traditio- nal culture method in combination and PCR-DGGE fingerprint technology was applied to study bacteria populati- on structure in Cantonese Sausage, and fermentation advantage bacterial community of Cantonese sausage has been analysised. The results showed that 19 strains of staphylococcus, 12 strains of lactic acid bacteria has been obtained by the traditional culture method, four strains of staphylococcus (named P1 to P4) and two strains of lactic acid bacteria (named L1 and L2) was identified by using physiological-biochemical characteristics. Three bands in the DGGE profiles of total bacterial DNA of Cantonese Sausage were not recovered by cultivation. Conversely, one bacterial species did not exhibit bands in DGGE fingerprints of total bacterial DNA. sequence analysis and similarity comparison showed that the P1 and P4 pertain to Staphylococcus xylosus, P2、 P3、 L1、L2 respectively pertain to Staphylococcus cohnii, Staphylococcus epidermidis, Lactococcus garvieae, Lactobacill- ales bacterium. The main culturable predominant bacteria in Cantonese Sausage were Staphylococcus saprophyti- cus, Lactobacillales bacterium, Staphylococcus xylosus. Conclusion:a combination of traditional separation and PCR-DGGE method could been applied to analysis of the bacteria community structure and advantage bacterium in Cantonese Sausage effectively and comprehensively, Screened advantage strains, layed the foundation for the research of developing of culture starter.

Analysis of Amino Acid Compositions in Eri Silkworm (Samia cynthia ricini) Pupa
2013, 34(4):  161-164. 
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Abstract: Objective To analyse of amino acid compositions in eri silkworm pupa, and offer scientific grounds for comprehensive utilization research of eri silkworm pupa. Method Kjeldahl method and Auto amino acid analyzer. Result The content of protein in eri silkworm pupa is 66.94±0.89%, and there are 17 kinds of amino acids, including glutamic acid(Glu)5.180±0.15%, aspartic acid(Asp) 4.317±0.08%, glycine(Gly)3.431±0.06%, leucine(Leu)3.184±0.21%, valine(Val)2.662±0.07%, phenylalanine(Phe)2.510±0.07%, tyrosine(Tyr)2.489±0.08%, lysine(Lys)2.365±0.12%, arginine(Arg)2.334±0.15%, alanine(Ala)2.205±0.18%, isoleucine (Ile)2.166±0.19%, proline(Pro)2.089±0.14%, threonine(Thr)1.901±0.16%, serine(Ser)1.863±0.13%, histidine(His) 1.722±0.12%, methionine(Met)0.983±0.11%, cysteine(Cys)0.696±0.04%.

Determination of Five Heavy Metals in Tea-camellia Seed Oil by Microwave Digestion-ICP-MS
2013, 34(4):  165-167. 
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Abstract: A method was studied for analysis of Pb,Cd,Cr,Cu and As in tea-camellia seed oil by using ICP-MS. The instrument parameter and microwave digestion condition were optimized and internal standard of 187Re,103Rh and 45Sc was selected to compensate the drift of analytical signals. The detection limits of these 5 elements were 0.36-1.64μg/kg. The addition standard recovery was 84%—111% ,and the RSD was 1.6%-7.6%(n=5) for 5 elements. The accuracy of the method was evaluated by the analysis of corresponding trace heavy metal elements in standard reference material (GBW10016 and GBW10019). The analytical method presented was characterized with rapidness, good precision, accuracy, low limits of detection.

Stimultaneous Determination of 11 Flavonoids in Citrus by Ultra Performance Liquid Chromatography
2013, 34(4):  168-172. 
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A rapid method for qualitative and quantitative analysis of 11 flavonoids in citrus was developed using ultra performance liquid chromatography (UPLC) coupled with photodiode array detector. Under the condition of methanol-.acetic acid water solution as mobile phase and gradient elution, 8 flavanones and 3 polymethacrylate flavones were separated to baseline within 11 min. The detection wavelengthes were 283nm and 330nm. The limits of detection (LODs) were from 0.005 to 0.02mg/kg (S/N=3) and good linearity was observed with the correlation coefficient (r2)≥0.9991.The influencing factors sample preparation were optimized by using Orthogonal experimental design and the recoveries of compounds analyzed from peel and juice samples were in the range of 94.6–101.2% with RSD between 1.1 and 3.7%, and in the range of 94.5–101.8% with RSD between 0.9 and 3.9%, respectively.Compared with the existing, this method was more effective, environmentally friendly and reproducible.

Analyses of Components and Fermented Flavor substances of Libo Sour Meat in Guizhou during Fermentation
2013, 34(4):  173-177. 
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Alternation and analyses of components and fermented favor substances of Libo sour meat in Guizhou during fermentation were investigated in this paper. The results showed that pH value of sour meat trended to decrease, especially at first 10 days, lowering from pH 7.20 to 4.50, and further to 3.60 at 45 days. Protein and fat of sour meat displayed an increasing tendency with decreasing water, but an opposite trend was found for total sugar. Metabolites such as total acids, amino acids nitrogen, free amino acids and total volatile salt-basic nitrogen increased gradually with the fermentation period. 34 spices of compounds related to flavor of traditional sour meat were found, including 15 acids, 11 aldehydes, 1 hydrocarbon, 1 allyl, 3 estercoholdens, and 3 alcohols, with acids being the major compound which accounts for 44% of total flavor compounds.

The Analysis of Nutritive Composition in Natural Green Eggs of Changbai Mountain Area
2013, 34(4):  178-182. 
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Abstract: In order to investigate the nutritional and functional composition of natural green eggs in Changbai Mountain area, the content of moisture, crude fat, ash, protein, mineral (sodium, potassium, calcium, iron, magnesium, zinc), vitamin A, vitamin E and other nutrients, as well as cholesterol and lecithin and other functional components of the natural green eggs were measured. And then the contents were compared with those of conventional eggs and free range eggs. The results obtained from the study show that, the moisture content in the natural green eggs is lower, and there is no obvious difference in the crude fat content among the three kinds of eggs, but the ash and protein contents are higher than those of the other two kinds of eggs. Potassium, sodium, calcium, magnesium contents in the natural green eggs, but the content of iron and zinc were close to conventional eggs, and below free range eggs. The natural green eggs also have fine quality with high vitamin A, vitamin E, lecithin yet low cholesterol.

Determination of the Inorganic and Organic Selenium Contents in duck eggs by Hydride Generation-Atomic Fluorescence Spectrometry
2013, 34(4):  183-185. 
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A method for the determination of organic and inorganic selenium in duck eggs by Hydride Generation-Atomic Fluorescence Spectrometry (HG-AFS)had been developed. A sample was extracted with the buffer solution of Tris (hydroxymethyl) aminomethane-hydrochloric acid (Tris-HCl) in PH=8.6,deposited with Ammonium sulphate. The total selenium and inorganic selenium content were detected with HG-AFS. The content difference between total selenium and the inorganic selenium was organic selenium content. The detection limit for selenium was 0.003mg/kg under the optimum condition. The linear range was 2.0-50μg/L.The relative standard derivation was less than3.21%. The recoveries was 82.8-91.0%. The inorganic selenium and organic selenium content were detected respectively from the selenium enriched duck eggs by this method. This method met the determination of organic selenium in duck eggs.

Analysis of Aroma Components in Jingwu Duck Neck with Different Flavors Using Solid Phase Microextraction coupled with Gas Chromatography-Mass Spectrometry
2013, 34(4):  186-189. 
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The aroma components in sauce flavor duck neck and spicy flavor duck neck were extracted by solid phase micro-extraction (SPME) and analyzed by gas chromatography-mass spectrometry (GC-MS). The results indicated that 16 and 23 aroma components from sauce flavor duck neck and spicy flavor duck neck were indentified respectively, mainly including alcohols, ethers and alkanes. Linalool, 1-methoxy-4-(1-propenyl)-benzene, β-pinene, D-limonene and 1-methyl-4-(1-methylethyl)-1,4-cyclohexadiene were the main aroma components in Jingwu duck neck. In addition, the number of unique aroma components in sauce flavor duck neck and spicy flavor duck neck were 3 and 10 respectively.
Comparative study on the aroma components in the purple potato wine during the aging
2013, 34(4):  190-194. 
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Abstract: To investigate the influence of aging on the aroma components in the purple potato wine, the solid-phase micro extraction (SPME) and the gas chromatography-mass spectrometry ( GC-MS) were adopted to separate and identify the aroma components during the aging. The relative contents of aroma components were determined by area normalizing method. The results demonstrated that 60 of aroma components were all identified in the aging with isoamyl alcohol, ethyl decylate, ethyl octanoate and so on. Among those, the relative contents of Isoamyl alcohol, ethyl octanoate, benzyl ethanol and so on were higher. But the species, main compound and its relative content were different during the aging. The relative contents of esters and ketones increased totally, and the relative contents of alcohol decreased. The relative contents of acids changed slightly, and the relative contents of phenols increased slightly.

Difference of Volatile Odor of Fish Sauce Made from Different Fishes
2013, 34(4):  195-198. 
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The volatile compounds of fish sauce made from different fish by traditional processing were investigated by GC-MS and electronic nose respectively. The results were compared by original fish sauce with best flavor quality. The results showed that fish sauce made from different fish has different volatile compounds indeed. Fish sauce made from brown-striped mackerel scad has more volatile compound, the 19 volatile compounds involved 3 sulfur-containing compounds, 6 aldehydes and 4 volatile fat acids. Fish sauce made from Bluefin leatherjacket has 9 volatile compounds. Anchovy decayed easily especially young anchovy, so it usually made for fish sauce, but the volatile compounds of anchovy fish sauce were not very abundant in fact, particularly for young anchovy. The study found that more content of protein and amino acids, especially for more sulfur-containing amino acids were more favorable for the characteristic volatile odor forming, fishes with more fat content are not suitable for fish sauce processing.

Comparison of Methods for DNA Extraction from Soybean for Detection of Genetically Modified Organism
2013, 34(4):  199-203. 
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The objective of this study was to screen a suitable method for DNA extraction from soybean by comparison of five generally applied DNA extraction methods. After extraction, the quality of soybean DNA was examined with ultraviolet spectrophotometry, agarose gel electrophoresis and real-time fluorescent PCR, respectively. The results showed that the DNA extracted by Bayer method contained many PCR inhibitors; the purity and yield of DNA extracted by Monsanto method did not meet the demand of the quality standard of DNA in molecular experiment; DuPont method, Qiagen kit and Tiangen kit could extract high-quality DNA which was suitable for real-time fluorescent PCR, but Qiagen kit cost too much. These evidences indicated that DuPont method and Tiangen kit were suitable methods to extract DNA from soybean for detection of genetically modified ingredients.

Simultaneous determination of heavy metal content in Strawberry with inductively coupled plasma atomic emission spectrometry (ICP-OES) digested by dry-ashing, wet digestion and microwave digestion respectively
yanxia zeng
2013, 34(4):  204-207. 
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A subject for the simultaneous determination of the content of trace heavy metals including Cd, Cr, Cu and Pb in 5 spieces of Strawberry after dry-ashing, HNO3 digestion and microwave digestion by ICP-OES was established. The contents of Cd, Cr, Cu and Pb in Strawberry are Simultaneous determinated and compared with Standard tolerance.The results show that, the contents of trace heavy metals in five species of Strawberry samples doesn’t exceed the standard. The rates of recovery of testing rusults digested with dry-ashing, HNO3 digestion and microwave digestion are 85.3%-104.5%,93.2%-104.6%,92.8%-106.3% respectively. It can be also showed that RSD% is below to 20%. The methodological study showed that the method method is accurate and reliable for the detection for the contents of Cd, Cr, Cu and Pb while for the contents of As is not suitable.It can be concluded that the method is simple,fast and accurate for the quickly Simultaneous determination the contents of trace Cd, Cr, Cu and Pb in Strawberry by using inductively coupled plasma atomic emission spectrometry.It can be also concluded that the contents of trace heavy metals in Strawberry samples doesn’t exceed the standard, and that the possiblity of the heavy metal pollution in Strawberry is little.
Analyzed Variation Trend of Limonin in Fermentative Broth Citrus Juice by UPLC-MS/MS
2013, 34(4):  208-211. 
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Abstract: Objective: Determined the limonin in the citrus juice fermentative broth by UPLC- MS/MS, analyzed the limonin’s variation trend in citrus processing fermentation products. Method: The column was waters ACQUITY BEH C18 (50 mm x 2.5 mm,1.9μm); Mobile phase: Using gradient elution, A was acetonitrile and B was water, A: 10%(0min)-50%(3min)- 10%(4min)-10%(5min);The velocity of flow was 0.3 ml?min-1; column temperature was 40℃; Injection quantity was 5μL; Detection time was 5min; ESI (+) scan, the limonin’s parents were m/z=471.1 , daughter were m/z=425.3 and m/z=161.1; Result: Limonin can be detected at the analytical conditions, Limonin’s content was change from the fermentation time, preservation of the longer, lower the content of limonin. Conclusion: citrus juice fermentative broth is extended the storage time, which is conducive to the removal of bitter substances.

Evaluation of the Debittering about Casein Hydrolysates rich of ACE Inhibitor Peptides Using Electronic Tongue
2013, 34(4):  212-216. 
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Abstract: Debittering the casein hydrolysate with flavor enzymatic, electronic tongue technology combined with the sensory evaluation method was used to evaluate the debittering effect, and the ACE inhibitory activity of hydrolysate before and after debittering was detected by HHL method. The results showed that there are some differences between sensory evaluation method and electronic tongue technology, the latter have more advantage at resolution, sensitivity, stability and so on than former. Indicating the debittering effect with bitterness and after-bitterness for the nine kinds of products from orthogonal test, The results showed that the sample 3 has the best debittering effect which was prepared under the conditions of that ratio of enzyme to substrate is 2800u/g, pH valule is 6.8, hydrolysed time is 2.5h, in order to obtain the more active sample, four samples (3, 6, 8, 9) with good debittering effect and casein hydrolysate without debitting were compared IC50. The results showed that IC50 of sample 9 (0.28mg/mL) was similar to IC50 of hydrolysate without debittering (0.27mg/mL).

Study on Constituents of Volatile Oils of Toona sinensis
2013, 34(4):  217-220. 
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Effects of Pre-harvest Treatment with Nanometer Nutrient Solution on the Quality of Tomato Fruit
2013, 34(4):  221-225. 
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Tomato fruit (Solanum lycopersicum L.cy.lichun) were used to study the effect of treatment spraying branches with 3% nanometer nutrient solution and fertilizing treatment mixing 3% nanometer nutrient significantly improved the titratable acid content by 20.4% and the soluble protein content by 37%.Fertilizing treatment significantly improved the titratable acid content by 22.2%, the soluble protein content by 30% and the lycopene content 1.9 times.Two treatment also significantly improved the content of sugar-acid ratio, total soluble sugar , Vitamin C, total phenols and flavonoids, but no significantly effect on reducing sugar content. Tomato aromatic substance detecting by GC-MS, showed that two treatments increased (Z)-3-Hexenal, (E)-2-Hexenal, 6-methyl-5-Hepten-2-one,Methyl salicylate, Ketone and esters increased by spraying treatment and Long Chain Alkane, and (E,E)-2,4-Hexadienal increased by fertilizing treatment is effective than spraying treatment.

Effect of final vacuum cooling temperature on the properties of Tofu
Bing-Xing SHI
2013, 34(4):  226-229. 
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The effect of final temperature(4℃、6℃、8℃) on the vacuum cooling performances of tofu was studied, including the cooling rate, weight loss and typical property changes (protein, water binding capacity, pH value, hardness, colour and luster) during the storage period of a week at 4℃. The results indicat that effects of final temperature on cooling rate and weight loss were not significant. However, the different final temperature(4℃、6℃、8℃) on the vacuum cooling performances for the quality of tofu(protein, water binding capacity, pH value, hardness, colour and luster) had significant influence. The conclusion was drawn that 4℃ is considered as the best final temperature for tofu ,which can be stored with 4℃ for five days without significant quality change.

Evaluating freshness of chilled tilapia fillets by adenosine triphosphate degradation compounds
2013, 34(4):  230-235. 
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Changes in adenosine triphosphate (ATP) degradation compounds measured by reversed phase-high performance liquid chromatography (RP-HPLC) were monitored during storage of chilled tilapia fillets, and new freshness indicators as Ki、H、Fr value were proposed. The fillet freshness were evaluated by integrated measurements of sensory attributes, total volatile basic nitrogen, psychrotrophic bacteria, ATP degradation compounds and their proportions as K related values. The results showed that the concentrations of ATP degradation compounds could be deceted exactly and rapidly by RP-HPLC; during chilled storage of tilapia fillets, it is found that ATP was degraded rapidly into inosine monophosphate (IMP); the content of ATP, adenosine diphosphate (ADP) and adenosine monophosphate (AMP) kept no more than 0.50μmol/g, IMP reached the highest level of 3.88 μmol/g initially and degraded into HxR (inosine) and hypoxantjine (Hx) with the storage time, and mainly accumulated Hx; Hx were in very low level initially, and increased gradually into the end level of 2.35 μmol/g with the decrease of freshness; rapid increase of Hx in spoilage phases were high correlation with microbiological metabolite off-odors. K value had highest correlation with sensory assessment and microbiological counts, H value and Hx could be alternated K value as freshness indicators.

Effect of Ginger Extract on Preservative of Fresh-cut Apple
2013, 34(4):  236-240. 
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Abstract: The effect of ginger extract on preservation of fresh-cut ‘Red Fuji’ apple was researched under immersing process with different concentrations, and physiological-quality indexes and microbial dynamic change were determined during the storage period. The results showed that: the respiratory rate and ethylene release quantity were significantly delayed. The weightlessness rate and the loss of acid titration were significantly reduced. The PPO activity and the accumulation of MDA were effectively inhibited. Combined with sensory quality that fuzzy evaluation, the best preservation effect was the 0.1g?ml-1ginger extract.

Application of complex fresh-keeping agent of chitosan on cold-stored litchi
2013, 34(4):  241-244. 
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The fresh-keeping effect on litchi which were storaged at 4±1℃ after drug treatment of the complex agent comprised by the mixture of antibacterial agent (natamycin, sodium diacetate) and antioxidant (tea polyphenols, ascorbic acid) with chitosan was studied. The results showed that when sorted at 4±1℃, the complex of 10g/L chitosan, 0.2 g/L natamycin, 10 g/L tea polyphenols and 19.2 g/L citric acid had an effective inhibition on the decay of litchi, the color change of its pericarp, the increase of PPO and POD activity and the decrease of the soluble solid content. Furthermore, it had a relatively satisfactory effect on improving the sensory quality of litchi. No decay was detected on the litchi coated with this complex fresh-keeping agent after storage under 4±1℃ for 18 days. Namely, through a sensory evaluation, the color of the pericarp, taste and flavor of the pulp and overall acceptability of litchi were 7.0, 6.3, 8.0, 7.0, respectively, which was significantly better than that of control group, 4.1,4.0,2.9, 3.1, respectively. Meanwhile, the activity decrease was 47.4% for PPO and 49.0% for POD compared with the control group.

Development of quality kinetics models and quality characteristics of farmed Oreochromis niloticus
QUAN YOU GUO WANG Xi-Chang
2013, 34(4):  245-249. 
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Sensory, chemical and microbiological characteristics of cultured Oreochromis niloticus stored aerobically at low from 0 to 10 degree and ambient temperatures at 25 degree were carried out, and the shelf lives and bacterial flora at the end of shelf life were also studied, meanwhile the predictive model of shelf life using square-root relative spoilage rate equation was developed. The results showed that the freshness of cultured Oreochromis niloticus at the initial time was excellent, its mean values of total viable count, Pseudomonas spp count, H2S-producing bacteria count and total volatile basic nitrogen were 4.41±1.13、3.39±1.09、2.01±0.88 lg(cfu/g)和8.53±0.73mg/100g, respectively. The freshness index including total viable count, Pseudomonas spp count, H2S-producing bacteria count and total volatile basic nitrogen of cultured Oreochromis niloticus stored aerobically at low temperature reached 7.79±0.35、7.24±0.45、6.35±0.23 lg(cfu/g)和19.90±2.10mg/100g,the shelf life of fish stored at low temperature was from 5.5 days to 20.1 days, their dominated bacteria was Pseudomonas spp. The shelf life was 1.1 days at ambient temperature , its dominated bacteria was Aeromonas spp. The parameter(minimum temperature) of quality kinetics model of cultured Oreochromis niloticus stored from 0℃ to 25℃ was -8.9℃.The shelf life models of relative rate of spoilage were validated under isothermal (3and 8℃) and non-isothermal conditions,indicating the predictive model of shelf life can efficiently evaluate the quality of cultured Oreochromis niloticus stored from 0℃ to 25℃.

Effects of Ultra-high Pressure Treatment on Shelf-life of Nanjing Salted Duck
2013, 34(4):  250-254. 
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In order to understand the effect of ultra-high pressure (UHP) treatment on the shelf-life and quality index of Nanjing salted duck, the vacuum-packaged duck breasts were subjected to UHP (200 and 400 MPa) treatment at 20℃、30℃、40℃ for 10 min. All samples are stored at 4℃. Total counts of spoilage microorganisms in UHP-treated and control breasts, were determined every week of storage. In addition, pH color, TBARS were assayed and sensory analysis was performed. The results indicated that UHP treatment could effectively inactivate initial microorganisms and inhibit growth of microorganisms in Nanjing salted duck breast. At the beginning of storage, UHP-treated breasts revealed increased. However, at the late storage period, no evident change of TBARS value in breasts with UHP treatment was observed. Breasts after UHP treatment evidently have a higher pH value than untreated samples. UHP treated breasts can not be distinguished from untreated samples in sensory analysis. Therefore, UHP treatment can effectively extend the shelf-life of Nanjing salted duck, and will not result in obvious changes of quality index in Nanjing salted duck, thereby better maintaining original product quality and taste.

Effects of storage temperature on the carotenoid content of ‘Cara Cara’ navel orange (C. sinensis Osbeck)
2013, 34(4):  255-260. 
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Carotenoids affect the external fruit quality and nutritional quality of citrus fruit greatly. In present study, effects of storage temperature (20°C and 4°C) on the carotenoid contents in fruit of ‘Cara Cara’ navel orange (C. sinensis Osbeck) was investigated. Results showed that the storage temperatures affected the carotenoids contents in peel and pulp of ‘Cara Cara’ in a tissue-specific manner. Room temperature (20°C) showed a positive role in pigmentation in peel of ‘Cara Cara’ only before 5 weeks of storage, but the total carotenoids remained a nearly stable level as time progressed. Low temperature (4°C) could maintain the carotenoid contents in the peel before early storage, but the contents were lower than those under room temperature. Except a slight increase in contents of β-carotene, lutein, α-cryptoxanthin at 10 weeks of storage, carotenoid contents in the pulp stored at 20 °C was not influenced. In contrast, the contents of carotenoid in the pulp under low temperature reached the peaks at 1 week of storage, and then remained nearly stable levels.

Influence of fat addition and frozen storage time on oxidation and gelation of myofibrils from frozen dumplings fillers
Baohua Kong
2013, 34(4):  261-266. 
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The objective of the present study was to elucidate the effect of fat addition and frozen storage time on the oxidation and gelation of myofibrils from frozen dumpling fillers. The oxidation and gelling ability of myofibril extracted from fillers in the frozen dumplings were studied in order to evaluate the quality deterioration mechanism of frozen dumpling during frozen storage. The carbonyl content, heat-induced gelatin viscosity and sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE) of myofibrils of frozen dumplings were determined. The results indicated that with the prolongation of frozen storage time, the carbonyl content in the myofibrillar protein increased significantly (P < 0.05). The storage modulus (G') and the peak temperature of myofibril protein decreased gradually. The SDS-PAGE showed that the percent of myosin heavy chain (MHC) and actin reduced and myosin light chain2 disappeared at 180d of frozen storage. Because fat oxidation could cause protein oxidation, the myofibril protein denatured seriously for more addition of fat in dumpling, which would further affect the gelling ability and viscoelasticity of protein. Therefore the quality of frozen dumplings decreased with increasing fat content and extending storage time.

Effect of Exogenous Vitamin A and Calcium Treatment on Tomato Refrigeration
2013, 34(4):  267-271. 
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Studying the impact on chilled “Liao yuan duo li” tomatoes by spraying exogenous vitamin A and humic acid calcium on the surface of the leaves. The result of the experiment shows: for each team the firmness, the soluble solids, the content of vitamin C, proline content and the activity of superoxide dismutase tended to decrease in the period of being chilled. The firmness would be 49.5% higher by using the mix of 2% vitamin A and 0.5% humic acid calcium than the comparation. The activity of peroxidase would increase along with the extend of the cold storage. The minimum of the MDA was 1.548nmol/g by using the mixture of 2% vitamin A and 0.5% humic acid calcium. Both of the activities of the lipoxygenase and catalase went up at the beginning and then drop down. The red-converting index showed an increasing trend and the best red-converting efficiency resulted from the treatment of 2% vitamin A and 0.5% humic acid calcium,which revealed 50.25% higher than the control. Weight of single tomato was up to 205.14g in the 2% vitamin A and 0.5% humic acid calcium. The mix of 2% vitamin A and 0.5% humic acid calcium would not only preserve the quality , but also extend the senescence of the tomatoes.
Analysis of Quality and Prediction of shelf life of Film Packaged Celery
2013, 34(4):  272-276. 
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The quality changes of film packaged celery stored at (-1±0.5)℃、(4±0.5)℃、(9±1)℃ and (19±1)℃were evaluated during storage. The shelf life was predicted by Q10 model, and 3T theory was applied to simulate postharvest circulation. Results showed that celery stored at (-1±0.5)℃ had good preservation quality, which combined with film packaging could inhibit the increase in weight loss rate, the decomposition of chlorophyll, the decline of sensory quality effectively, and keep the nitrite content at a lower level, therefore, it would prolong the shelf life of celery. Meanwhile, the prediction equation of shelf life in -1~9℃、9~19℃ and the quality loss and remained shelf life during different time and temperature were also attained.
Effect of low oxygen modified atmosphere packaging system on quality of fresh shiitake mushrooms
2013, 34(4):  277-283. 
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Effect of O2、CO2 、headspace and their combination of low oxygen modified atmosphere packaging system on quality of fresh shiitake mushrooms was investigated using response surface methodology(RSM). Results showed that headspace had the greatest impact on quality of mushroom as PPO activity, crude protein and total sugar content had reached a highly significant level, and the interaction between headspace and O2 had also researched a significant level. While the impact influenced by headspace and CO2 was not significant. And the interaction between O2 and CO2 had significant effect on total sugar content and PPO activity, but the effect on crude protein content was not significant. And the optimum conditions obtained according to the regression analysis of those three factors were as follows. O2: 4.59%, CO2: 20.13%, headspace: 0.67. PPO activity, crude protein and total sugar contents in mushrooms in optimizing conditions were 5.00U, 0.54% and 52.08%. Key words:Shiitake mushroom; modified atmosphere; Quadratic rotation-orthogonal composite design; Response surface.
Preparation of High molecular soluble soybean polysaccharides and Study on the fresh-keeping effect of it coating on eggs
2013, 34(4):  284-287. 
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High molecular soluble soybean polysaccharides (H-M) were prepared with aptly method and ultrafiltration from the soybean risidue. Fresh-keeping material was prepared by using H-M as a main substance and sodium alginate and potassium sorbate as trimmings. Along with this, the effect of H-M coating on the eggs surface structure, weight losing rate, H.U. and Y.I. stored at ambient temperature was investigated. Results showed that this new-type fresh-keeping material could seal up the air hole on the surface of eggs well and still exhibited excellent quality as an A level during storage for 30 days during the storage.
Experiment to Effects of Transparent Packaging on Pickled Mustard Tuber's Quality
2013, 34(4):  288-292. 
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Taking the new-producing pickled mustard tuber which does not mix with any condiment as raw materials, choosing 7 kinds of transparent plastic packing material and a non-transparent one as reference, we produce pickled mustard as ordinary production process and use modern method to analyse the quality of the pickle which are packed by the selected plastic packing material and stored under natural conditions. By performing the experiment, it is concluded that the A packaging group has best quality than other packaging groups except the control one in color, smell pickle sensory quality and total acid, amino nitrogen, reducing sugar, Vc etc chemistry; the pickled mustard tuber packed by PA/RCPP、PA/CPE have better quality; the other packed by PET/PE(big)、PET/PE(small)、BOPP/PE、BOPP/CPP have bad quality in colour and smell which are unacceptant.So A is a good transparent material to keep the quality of pickled mustard.
Research on compounded health beverage of Cordyceps militaris and hawthorn
Lin Biao-sheng
2013, 34(4):  293-297. 
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In this paper, the sucrose, citric acid and stabilizing agent were added to fermented liquid of Cordyceps militaris and hawthorn for compounding and formulation to research on Cordyceps militaris health beverage with hawthorn flavor, and the response surface method was used to optimize the formulation ration of compound parameters. The results indicated that optimal technological conditions were: fermented liquid of Cordyceps militaris-hawthorn compounded 74.49%, sucrose 6.06%, citric acid 0.11%, stabilizing agent 0.15%. On this condition, the appearance, shape, color and luster, taste of compounded health beverage were best, the comprehensive grade was highest, and the products qualities conform to the state standards of food sanitation.