2016, 34(6):1-6. DOI: 10.3969/j.issn.2095-6002.2016.06.001
Abstract:Non-targeted detection technique has been extensively applied in the food safety and quality in recent years. In general, a non-targeted detection combines analytical approaches,fingerprinting techniques and chemometrics to detect toxicants or foreign components in foods without knowing their chemical structures. The key purpose of non-targeted detection technique is to detect whether the sample is abnormal, without prior knowledge of what caused the abnormality. This manuscript introduces and reviews the current progress and the prospect non-targeted food detection techniques, including chromatographic, mass spectrometric, spectroscopic, cell-based non-targeted detection techniques. Foods and ingredients including milk, Chinese wolfberries, Chinese angelica,oregano, honey, etc., were introduced. The non-targeted detection technique can help the healthy development of food industry and play an important role in protecting public welfare and human wellbeing.
2016, 34(6):7-11. DOI: 10.3969/j.issn.2095-6002.2016.06.002
Abstract:Pulses are environmentally friendly crops which are high in fiber and carbohydrate and low in fat and hypo-allergenic. The year of 2016 has been declared as “International Year of Pulses” by the United Nations. China is one of the largest producers and consumers of pulses worldwide, with a long history of pulses cultivation and consumption. The utilization and promotion of pulses will contribute to the nutritional security and sustainable development of Chinese food. However, the development of Chinese pulse industry is still in the primary stage. Pulses are a sort of healthy food resources, while their role in dietary pattern has not been widely noted. In this paper, the quality and safety issues of pulses were summarized, and the countermeasures of these problems were discussed.
2016, 34(6):12-16, 30. DOI: 10.3969/j.issn.2095-6002.2016.06.003
Abstract:Soybean protein is widely used in food processing as raw materials, at the same time is a good source of amino acids that can be ingested by human beings. In order to improve the functional properties of soy protein in industrial production, the modifications are usually made, causing the low amino acid digestion and absorption. This review summarized the functional properties and nutritional value of soybean protein, the main modification and its influence on amino acid availability, and the present researches of soybean protein, put forward some suggestions and research directions in the future, and comprehensively presented the amino acid inefficient problem of soy protein resulted from modifications. This study also explained the relationship between the protein aggregates and the amino acid digestibility, and provided some suggestions about improving the utilization rate of soybean protein and innovation of production.
2016, 34(6):17-23. DOI: 10.3969/j.issn.2095-6002.2016.06.004
Abstract:Yeast cells’ activity and tolerance to freeze-thaw stress has an important influence on fermented products and frozen-dough technology. Soy peptides, casein peptone, and yeast nitrogen base were used as different yeast medium nitrogen sources to culture yeast cells. The effects of soy peptide on yeast cells’ activity and the tolerance to freeze-thaw stress were evaluated based on the growth curves, survival rates after freezing, cell wet weights, and dough fermentation. The results showed that the more soy peptides were added, the more yeast biomass was obtained, which did not increase when soy peptides reached 25g/L or higher. Therefore, the optimum amount of soy peptides was 25g/L. Yeast cells had a higher survival rate when they were incubated in media containing soy peptides, and the corresponding dough also retained better fermenting capability after freeze-thaw steps. Compared with other nitrogen sources, soy peptides increased the cell biomass and improved the cell tolerance to freeze-thaw stress and the fermentation effect.
2016, 34(6):24-30. DOI: 10.3969/j.issn.2095-6002.2016.06.005
Abstract:Functional surimi products with antioxidant activities were developed in this study. The enzymolysis was applied to produce mussel antioxidant peptides and neutral protease was the best protease. The optimized conditions were obtained by the orthogonal design, which were enzymatic temperature 45℃, enzymatic time 1h, the amount of enzyme 1500U/g, and the ratio of material to liquid 1∶5g/mL. Under this optimized conditions, the yield of peptides was (73.62±0.86)mg/g. Frozen dried enzymatic hydrolysates (>2%) had the antioxidant effects on lard in kamaboko gel and the variance analysis showed that it had the obvious antioxidant effects on lard. The results demonstrated that kamaboko gel including mussel antioxidant peptides is one kind of functional foods.
2016, 34(6):31-35. DOI: 10.3969/j.issn.2095-6002.2016.06.006
Abstract:The bacterial strain CICC 10820 isolated from life nutrition liquid was identified via 16S rRNA and tpi gene sequences analysis. According to the result, strain CICC 10820 was identified as Clostridium tertium. This research will provide the foundation for the further study.
2016, 34(6):36-40, 45. DOI: 10.3969/j.issn.2095-6002.2016.06.007
Abstract:The aim of the research was to discuss the inhibitory effect of polyphenol from lotus seed red-skin on α-glucosidase activity. It was designed to measure the α-glucosidase activity in different conditions using spectrophotometry. With the inhibitory effect on α-glucosidase activity as the index, the inhibitory conditions were optimized by the L9 (34) orthogonal optimization method. The results revealed that the optimal inhibition rate was 67.99%±1.79% at pH 6.8,1.50g/L of polyphenol concentration and 20min of reaction time. In addition, polyphenol was an anti-competitive inhibition type of inhibitor on α-glucosidase, and its inhibition constant was 0.24g/L.
2016, 34(6):41-45. DOI: 10.3969/j.issn.2095-6002.2016.06.008
Abstract:This study investigated the antioxidant activities of polyphenols in black garlic. According to “health food inspection and evaluation of technical specifications”, SPF grade KM mice were randomly divided into the blank control group, model control group and black garlic polyphenols groups. The mice in the garlic polyphenols groups were treated at a dosage of 2.04,4.10, and 12.25g/(kg·bw) for 30 days. The gastric oxidative damage was induced by bromobenzene oil. The liver tissues of mice in the control group and black garlic polyphenols treated groups were taken. The MDA contents, superoxide dismutase (SOD) activities, glutathione peroxidase (GSH-Px) activities, and total antioxidant capacity (T-AOC) in liver and serum were investigated. The results showed that the contents of MDA in serum and liver tissue of mice significantly decreased, and the activity of SOD, GSH-Px and T-AOC significantly increased with the increase of the crude extract. According to the standard of health food functional evaluation procedure and test method standard, it is concluded that the crude extract of black garlic has the function of antioxidation.
2016, 34(6):46-52. DOI: 10.3969/j.issn.2095-6002.2016.06.009
Abstract:Lathyrus sativus Linn. protein was extracted using the alkaline method and amino acid analysis and comprehensive assessment of nutritional value of protein were investigated. The analysis indicated that the optimized extraction yield of Lathyrus sativus Linn. protein was up to 26.1% under the condition of extraction temperature 40℃, pH 10, time 1h, and solid-liquid ratio 1∶20g/mL. The isoelectric point of Lathyrus sativus Linn. protein was pH 5 and 18 amino acids were found. The contents of glutamic acid and aspartic acid were 17.4% and 10.0%. The ratio of essential amino acids to total amino acids (EAA/TAA) was 42% and the ratio of essential amino acids to non-essential amino acids (EAA/NEAA) was 72.41% which were higher than the reference values proposed by FAO/WHO. Except for methionine + cystine, threonine, tryptophan, and valine, the contents of other amino acids were higher than WHO/FAO standard. Meanwhile, methionine+cystine and tryptophan were the first and second limiting amino acids. Moreover, the essential amino acids index (EAAI) of Lathyrus sativus Linn. protein was 1.16, which was higher than 0.9, the criteria for high-quality protein source. Thus, Lathyrus sativus Linn. proteins had high quality.
2016, 34(6):53-59. DOI: 10.3969/j.issn.2095-6002.2016.06.010
Abstract:Chestnut polysaccharide was extracted by water extraction method, enzyme-assisted method, and microwave-assisted method. According to single factor experiments, the orthogonal design was used to optimize the polysaccharide extraction process. The results showed that microwave-assisted extraction has the highest yield (9.34%), followed by enzyme-assisted method (7.36%) and water extraction method (6.24%). Analysis results by SPSS software showed that the extraction yields of the three methods had significant differences.
2016, 34(6):60-68. DOI: 10.3969/j.issn.2095-6002.2016.06.011
Abstract:Longan pulp fermented by lactic acid bacteria was used as base material. On the base of single factor test, a weighted composite score with the stability and sensory score was used as response value, and mathematical model was established by implementing four factors and three levels, with the purpose of determining the best formula of raw materials and stabilizer. The results showed that factors influencing the comprehensive score of cloudy longan beverage were in the order as follows:sugar acid ratio > pectin content > sodium alginate content> xanthan gum content. The research determined the best excipient formula:3.00% xylitol, 0.15% composite acid, 0.04% pectin content, 0.30% sodium alginate, and 0.02% xanthan gum. With this formula, the centrifugal sedimentation rate of the beverage was 7.36%, the sensory score and the comprehensive score were 89.3 and 98.97.
2016, 34(6):69-74. DOI: 10.3969/j.issn.2095-6002.2016.06.012
Abstract:Goat milk and its products contain abundant protein, fat and minerals, their nutritional components of goat milk are considered as the most similar to human milk compared to others. Due to containing smaller fat globules, low lactose and rich adenosine triphosphate (ATP) which facilitates lactose to decompose, goat milk is beneficial for Asian adults,infant and children with lactose intolerance. Consumption of goat milk and its products in home and abroad markets increased significantly, however, because of low production and high prices, some goat milk and its products have been readily adulterated with relatively cheaper cow milk or cow milk derived products. In order to protect consumer interests or health, to regulate the market and to avoid trading losses, it is urgent to identify authentic milk products and determine the amount of adulterated components. This paper summarized recent progresses on identification and detection methods, such as immunological, electrophoretic and chromatographic techniques, of cow milk derived components in goat milk and its products.
2016, 34(6):75-78, 84. DOI: 10.3969/j.issn.2095-6002.2016.06.013
Abstract:In alkaline medium, hydrogen peroxide oxidizes luminol and then produces chemiluminescence. Dimethoate could enhance the chemiluminescence intensity strongly, and thus a quick and direct flow injection chemiluminescence method based on luminol-hydrogen peroxide system was established to determine the content of dimethoate. The results indicated that the dimethoate concentration had a good linear correlation with chemiluminescence within the scope of 0.01 to 10mg/L. The detection limit of the method was 0.009mg/L. The relative standard deviation was 2.1% for eleven replicate detections of 0.5mg/L dimethoate. Using this system, the cauliflower samples were spiked with dimethoate and detected by this method with recovery ranging from 86.7%~109.5%.
2016, 34(6):79-84. DOI: 10.3969/j.issn.2095-6002.2016.06.014
Abstract:The existing quality and safety risk assessment methods for agricultural products are mostly the single factor evaluation. The valuation methods of other fields could provide new ideas for agricultural product risk assessment. The multi index evaluation methods, which are widely used in economic management field, can be applied to evaluate the quality of agricultural products. Due to the small sample size of agricultural products and the complexity of the relationship between agricultural products’ quality and environmental information, the grey forecasting model and correlation analysis methods are discussed in this paper. Moreover, according to the characteristics of different agricultural products to select appropriate auxiliary models can improve the risk assessment.
2016, 34(6):85-90. DOI: 10.3969/j.issn.2095-6002.2016.06.015
Abstract:Data mining technology has great application values and potential in the food safety field. The feasibility and advantage of the BP neural network algorithm were explained. The process of data preprocessing was introduced, and the experiment of data mining was designed then realized, focusing on sampling inspection data. Finally, by taking advantage of the mining results, a prediction of food inspection conclusions was put forward which verified the method’s practical value and guiding significance. The experiment indicated that data mining method based on BP neural network has favorable robustness and good accuracy. The predictions of unqualified food’s appearance can lead food safety sampling and inspection work in practice, which can put an end to the occurrence of food safety problems.