XIE Ming-yong , LIU Xiao-zhen , CHEN Yang-jie
2014, 32(1):1-7. DOI: 10.3969/j.issn.2095-6002.2014.01.001
Abstract:Nonylphenol (NP) is an endocrine disrupter, and the exposure of NP in foodstuff has attracted extensive attentions in the global. In this paper, the properties and applications of NP, exposure level in foodstuff, main sources, and toxic action to organism have been reviewed to provide scientific basis for the risk assessment and limit setting of NP.
2014, 32(1):8-11. DOI: 10.3969/j.issn.2095-6002.2014.01.002
Abstract:In connection with the concernment of consumers on the safety of genetically modified foods, the concepts, laws, and domestic situation of genetically modified foods were discussed taking the transgenic fruits and vegetables products for example. We hope that the consumers have the objective and impartial understanding on genetically modified foods, reduce controversy, and return to rationality by reading the paper.
2014, 32(1):12-16. DOI: 10.3969/j.issn.2095-6002.2014.01.003
Abstract:Fresh-cut fruits and vegetables are favored by consumers due to its fresh, sanitation, and convenience characters. The reasons of quality and safety incidents about fresh-cut fruits and vegetables in recent years were analyzed. Based on the technical standards and regulations and risk assessment system in some developed countries, suggestions and countermeasure to food safety incidents of the fresh-cut fruits and vegetables industry in China were provided.
DING Zhan-sheng , FAN Liu-ping
2014, 32(1):17-21. DOI: 10.3969/j.issn.2095-6002.2014.01.004
Abstract:The production of fruit and vegetable in China is massive, and their processing as well as imports and exports have developed rapidly in recent years. But there are some safety problems on processing and trade of imports and exports in fruit and vegetable, including microorganism and its toxin, the residual and added harmful materials during processing, the produced harmful materials during processing, as well as some harm from packing. By standardization of raw material, processing and product, these problems can be solved and the industry of fruit and vegetable can be developed normally.
JIANG Nan , XIU Lin , LIU Jing-sheng
2014, 32(1):22-26. DOI: 10.3969/j.issn.2095-6002.2014.01.005
Abstract:In this study,the cooking characteristics and textural properties of noodles being made of corn flour, modified corn flour ,and wheat flour were investigated. The results showed that hardness and elasticity of modified corn flour noodles were similar to these of wheat flour noodles. Chewiness of modified corn flour noodles was more than 86% of that of wheat flour noodles and the tensile property of modified corn flour noodles was about 50% of wheat flour noodles. Meanwhile, the toughness of modified corn flour noodles was about 70% of that of wheat flour noodles according to the broken characteristic analysis. The reduced cooking loss and broken bars rat of modified corn flour noodles were lower than these of wheat flour noodles. Compared with corn flour, modified corn flour could improve the quality characteristics of noodles.
SUN Zhi-jian , ZHANG Min , LIU Ming , TAN Bin , YIN Dong , GAO Le , SUN Fei-fei
2014, 32(1):27-33. DOI: 10.3969/j.issn.2095-6002.2014.01.006
Abstract:Using the twin-screw extrusion modification methods to process instant nutrition powder, the technological parameters:extrusion temperature, material moisture content, screw speed on the physicochemical properties of the product quality characteristics were studied. The results indicated that material moisture content, screw speed, and extrusion temperature significantly affected (P<0.05) the quality of barley nutrition powder product. The response surface experiment showed that the optimum processing conditions of instant nutrition powder were screw speed of 290r/min, temperature of 165℃, and moisture content of 16.5%. The indicators of barley pre-gelatinized flour obtained under the optimal conditions were expanded degrees 3.14, injectivity index 5.92, density 0.53, and IOD 5.44.
AN Lin , ZHANG Yan , CUI Yu , WANG You-sheng
2014, 32(1):34-39. DOI: 10.3969/j.issn.2095-6002.2014.01.007
Abstract:The antimicrobial activities, free radical scavenging capacity, the content of total phenols, and total flavonoids of primary and secondary distilled bamboo vinegar were investigated. In addition, the primary and secondary distillation bamboo vinegar was analyzed for the main bioactive compounds by HPLC. The results indicated that the bamboo vinegar displayed strong antimicrobial activities against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Canidia albicans and Aspergillus niger, and free radical-scavenging properties. However, antioxidant capacity and antimicrobial activities of secondary distilled bamboo vinegar were significantly lower than these of primary distilled bamboo vinegar. The HPLC fingerprint showed that the peak numbers and areas of secondary distilled bamboo vinegar at 254nm and 270nm were obviously lower than these of primary distilled bamboo vinegar.
LIU Xiao-sheng , LIU Jian-bin , LIU Meng-ya , HE Cong-cong , YANG Zheng-mao , SONG Huan-lu
2014, 32(1):40-46. DOI: 10.3969/j.issn.2095-6002.2014.01.008
Abstract:The odor active compounds in subcutaneous fat of Jinhua ham fermented for 18months were extracted by solvent-assisted flavorevaporation (SAFE) and simultaneous distillation extraction (SDE) methods and analyzed by gas chromatography-Olfactrometry-mass spectrometry (GC-O-MS). Totally 40odorants were detected by SAFE while 22odorants were detected by SDE. About 10odorants were identified as key odor active compounds, which were hexanal, heptanal, isopropyl disulfide, octanal, (E)-2-octenal, 3-methylbutanoic acid, (E,E)-2,4-decadienal, γ-decalactone, andγ-undecalactone.
CAO Xue-li , SONG Sha-sha , LONG Li-mei
2014, 32(1):47-52. DOI: 10.3969/j.issn.2095-6002.2014.01.009
Abstract:Quality assessment is necessary in the production and circulation of green tea. Color, aroma, taste, shape, and leaves are five elements for green tea quality evaluation. Currently, various methods being developed and applied in the quality assessment of green tea. Sensory evaluation methods have its own advantages and disadvantages while physicochemical methods can apply for the detection of a single component of green tea , but can not achieve the purpose of overall quality assessments. Intelligent sensory evaluation and the chromatographic fingerprint methods ,which are comprehensive, objective, and intuitive, combing the value of taste and aroma with the quality of green tea. It can not only be served as the potential analysis methods for the green tea classification and gradation, but also provide a new approach for accessment of food safety and quality.
YANG Ju-fang , ZHOU Zheng , WU Hao , Zha Meng-yin , CHEN Cun-she
2014, 32(1):53-58. DOI: 10.3969/j.issn.2095-6002.2014.01.010
Abstract:In this study, ultrasonic and vacuum freeze drying were combined to dry yogurt. Compared with the vacuum freeze drying, the effects of ultrasonic time, power, and pulse on water evaporation and drying time of yogurt were determined. Meanwhile, the drying kinetics model was established. The results showed that the ultrasonic synergistic vacuum freeze drying, significantly improving moisture diffusion of the material under the conditions of the low air velocity and low temperature, could shorten the total drying time. The optimal drying conditions were ultrasonic power 495W (55%), ultrasonic pulse 5∶3, and ultrasonic time 1.5h. Compared with the control group, the total drying time under the optimal conditions decreased 20.58h. Moreover, the drying kinetics model was Wt=W0e-Kt.
QI Xiao-yang , ZHANG Song-pei
2014, 32(1):59-64. DOI: 10.3969/j.issn.2095-6002.2014.01.011
Abstract:Tea saponin was extracted in camellia cakes using ultrasonic assisted water extraction. Effects of camellia cakes partical size, solid-liquid ratio, extraction time, and extraction temperature were investigated through the single factor and orthogonal method. Results showed that camellia cakes partical size, extraction time, and extraction temperature had significant effects on the yield of tea saponin, followed by the solid-liquid ratio. The highest yield of tea saponin (21.32%) was obtained under the optimal extraction conditions of camellia cakes partical size 60-100meshes, solid-liquid ratio 1∶9, extraction time 40min, and extraction temperature 50℃. Surface tension of tea saponin solution was determined and the applications of tea saponin solution to produce natural cosmetic products were analysed and prospected.
WANG Jian-qing , XU Li-hong , ZHANG Yu , WANG Wei , HU Qi
2014, 32(1):65-68. DOI: 10.3969/j.issn.2095-6002.2014.01.012
Abstract:The chemiluminescence technology was selected to establish a new method for the determination of sulfites in foods. Various factors affecting the chemiluminescence detection were evaluated and the optimum determination conditions were obtained in this study. The detection limit of the method was 4.6mg/kg. In the range of 1.0-10.0mg/L, the sulfite concentration was positively correlated with the luminous intensity value (ΔI), and the correlation coefficient (R2) was 0.9934. Spike recovery tests of six different samples were evaluated. The average RSD was 3.05% and the average recovery was 93.0%. Chemiluminescence determination results indicated that the new method was a good candidate for the qualitative and quantitative analysis of sulfites in foods.
CAI Qiang , WANG Jun-jun , LI Hai-sheng , MAO Dian-hui
2014, 32(1):69-76. DOI: 10.3969/j.issn.2095-6002.2014.01.013
Abstract:The accuracy of the food safety evaluation model directly influences the accuracy of food safety situation assessment and forecast. Based on the hazard analysis critical control point theory (HACCP), a food safety evaluation index system was established from the perspective of the food supply chain. In order to detect the convergence speed and fitting degree of the model’s deviation, the analytic hierarchy process was utilized to improve the random initialization calculating weight method in the backward propagation neural network algorithm. Meanwhile, the sample data were trained and the test data were validated. The results showed that the BP neural network combined with AHP was high-precision, fast, and objective, which could be used to food safety evaluation of circulation links of production, processing, and sales.
ZHANG Yun-xiao , LIU Hong-zhi
2014, 32(1):77-82. DOI: 10.3969/j.issn.2095-6002.2014.01.014
Abstract:Food safety issues are related to the national life, which affect many areas and are global. Based on the problems of China's food safety surveillance system, several countermeasures were applied to improve the institutional system, such as setting up the safety surveillance system model, combining multiple supervision agencies, and setting up the overall supervision model of food safety production. Applying the internet of things technology, especially sensor network technology to build a food safety surveillance information system can improve the surveillance means of food safety.