Food Science Commons^™

The Development Of Time Of Flight Mass And Its Applications On Food Quality And Safety Detection, Wu Weiliang, Li Xiaoming, Zhu Wenliang, Long Shunrong, Cui Haiping, Huang Cuili

Food and Machinery

The food contaminants and residues from food processing and food packaging materials are threating the food quality and safety, such as pesticide residue, veterinary drug, illegal non-food substances and organic pollutants. Therefore, the advanced modern detection methods are indispensable for food analysis. Meanwhile, the complex of food matrix and diversity of the food contaminants and residues also propose the higher requirements for food detection technology. The time of flight mass as one of the mass techniques is considered as a superior analysis technique and has been applied in food quality and safety analysis as a result of its high sensitivity …

Effect Of Endogenous Minor Constituents And Association Colloids In Vegetable Oil On Lipid Oxidation, Gao Wei, Ding Yangping, Yang Jian

Food and Machinery

The mechanism of free radical chain reaction in lipid oxidation has been summarized. In addition, the role of endogenous trace constituents, such as oxygen, water, free fatty acids, monoacylglycerol and diacylglycerol, etc, on the oil oxidation has been highlighted. The existence of association colloids self-assembled by the surface active minor constituents in vegetable oil and the corresponding action on oil oxidation has all been discussed. The limiting the presence of pro-oxidants and the degrading of antioxidants should be limited strictly during oil refining, for the critical control point to enhance vegetable oil quality.

Research Progress On Determination Method Of Mineral Elements In Milk And Dairy Products, Chen Danjin, Mu Guangqing, Jiang Tiemin, Liu Jichao, Zhao Junying, Li Hedan, Chen Lijun

Food and Machinery

The number of kinds and the corresponding capacities of mineral elements in milk and dairy products are key criteria to evaluate their nutritional quality. Thus choosing an efficient, sensitive and rapid detection method for mineral elements is important to the research, production, and trade of dairy products. This paper first discussed the pretreatment method for digesting milk or diary products, and then made comparisons among different detection methods, including flame atomic absorption spectrometry (FAAS), graphite furnace atomic absorption specteometry (GFAAS), hydride generation atomic absorption specteometry (HGAAS), atomic fluorescence spectrometric (AFS), atomic emission spectrometry (AES), inductively coupled plasma-mass spectrum (ICP—MS), enzyme-linked …

Progress On Refrigeration Systems And Cold Storage Methods Of Fishing Boats, Zhu Shixin, Xie Jing, Guo Yaojun, Wang Jinfeng, Tang Yuanrui

Food and Machinery

In the process of fishing on boats, refrigeration technology has a direct impact on the nutrition and economic value of catches. Based on the analysis of different refrigeration systems and methods of cold storage, the resent research progress on refrigeration systems was summarized, which might be useful to provide the basis for the improvements and optimization design of refrigeration system on the fishing boats. At present, there were four methods to keep the catches fresh by low temperature, such as iced preservation, sea water preservation, partial freezing preservation and freezing preservation. Among them, the former three refrigerated preservation methods usually …

Research Development On Preservation Methods Of Salmon, Zhang Ning, Xie Jing

Food and Machinery

Salmon has a delicious tasty and rich nutrition, but it’s perishable. Several current preservation methods such as cold storage, super-chilled storage, ice storage, controlled atmosphere were reviewed. The principles and characteristics of these methods were introduced. A review of research status in the preservation methods of salmon was analyzed, at the same time, some existing problems and future development trends of the preservation methods of salmon were also proposed.

Reasearch Progress On Application Of Fat Substitutes In Ice Cream, Chen Long, Liu Aiguo, Ji Ruiqing, Cehn Zhenzhen, Li Xiaomin

Food and Machinery

Fat substitutes can replace the fat of traditional ice cream, reduce heat, and promote the health of consumers. This paper reviews the research methods and results of recent research scholars to apply fat substitutes in ice cream. Forecast the problem exist and development prospects of fat substitutes.

Experience And Reference Of Criminal Regulation On Food Crime In Taiwan, Gu Yongjing

Food and Machinery

Food problem is a major issue related to national and social stability, but due to the constraints of various factors, food criminal regulation in Chinese exists provisions of "Criminal Law" and "Food Safety Law" lack of coordination, lack of support for food safety hazards regulation of a type of crime, lack of reasonable punishment setting and other issues. But Taiwan there are a rich experience in Taiwan, which not only focus on the convergence of food safety criminal law and other laws, but also has a wide range of criminal regulation of food safety in the penalty set Scientifically. Therefore, …

Research On Legal Regulation Of Genetically Modified Food, Dou Yusi, Jiang Wenyu

Food and Machinery

GM food is an important achievement in the development of biotechnology, and it has two sides as any other achievements. Taking into account the special nature of GM food, it needs to make effective legal regulation to regulate the impossible problems. Europe, Japan and other developed countries establish experimental and listing approval system, a isolation system and labeling system specifically. The US also sets up legal principle of non discrimination for supervision of GM food. Combined with the present situation of legal regulation on GM food in China, several steps should be taken, for adopting formal legislation, enacting specific workable …

Criminal Law And Regulation Of Food Safety In China, Zhang Fengxue

Food and Machinery

There are four major problems existing in China's food safety supervision and management. They are imperfection in the system of laws on food safety, obvious defect of current criminal law governing food safety crimes, insufficient understanding for supervisory staff to hazard of food safety crimes, absence of workable accountability system for supervisory staff who spoil their duty. Those existing problems have caused frequent crisis of food safety. To tackle these problems, a legally governing system, which should be mainly supported by the system of criminal law, needs to be established to unify names of crime for food safety crime and …

Study On Disclosure Systems Of Accounting Information In Food Enterprises For Social Responsibility, Lin Haichao

Food and Machinery

With the continuous development of China's economy, food security issues have become increasingly prominent. An important reason for food safety problems is the lack of corporate social responsibility. Chinese food enterprises are lack of social responsibility accounting system. The social responsibility accounting information disclosure is imperfect and weak sense of corporate social responsibility to food companies. The relevant laws are inadequate. Food companies should be part of the social responsibility of compulsory disclosure of accounting information. The government should develop and improve social responsibility accounting of relevant laws and regulations, and also should strengthen supervision and promote corporate social responsibility …

Food Safety Problems In Food Logistics And Related Measures, Zeng Yuying

Food and Machinery

Food safety and people's life and health are closely related, its importance is self-evident. The problem of food safety in food logistics mainly in several cases includes food spoilage, chemical pollution and breakage of packing and food expiring. The reasons for these food safety problems are many and varied, not only the logistics industry itself is inefficient, too many intermediate links, technology and self-discipline ability, lack of infrastructure investment, but also the unperfect legal system, the supervision in relevant departments. Therefore, the corresponding countermeasures should be found from two aspects in national and food logistics operator. National level can improve …

Comparative Analysis Of Bacterial Community Structure Of Chinese Fen-Daqus, Ye Guangbin, Wang Caihong, Wang Yi, Zhen Pan, Wang Yong, Luo Huibo

Food and Machinery

The bacterial community structure of three types Fen-Daqus (Qingcha Daqu, Houhuo Daqu and Hongxin Daqu) were studied through construction of bacteria 16S rRNA gene clone library, sequencing and phylogenetic analyses. The results showed that the bacteria communities of three types Fen-Daqus were both distributed in Bacilli, Actinobacteridae, Gammaproteobacteria. But there are some specific differences in detail composition of the bacterial species among the three types Fen-Daqus. Lactobacillus and Staphylococcus were the dominant bacteria in Qingcha Daqu (the ratio to total clones were 37.78% and 22.22% separately); Lactobacillus, Staphylococcus, Bacillus and Weissella were the dominant bacteria in Houhuo Daqu (the ratio …

Detection Of Common Defects In Jujube Fruit Using Hyperspectral Imaging, Wang Wanjiao, He Xiaoguang, Wang Songlei, Liu Guishan, Wu Longguo

Food and Machinery

A hyperspectral imaging technology combined with the principal component analysis (PCA) and the minimum noise fraction (MNF) methods were developed for the detection of common defects in Lingwu long jujubes, and investigated the influence of the background to recognition of defects. Firstly, the hyperspectral images of jujube samples (insect hole, crack and intact jujubes) were acquired. Secondly, the PCA and MNF methods were used to reduce dimensionality of hyperspectral images and to separate the noise from signals effectively. The PC1 and M1 images of insect hole and intact jujube, PC2 and M2 images of crack jujube were selected to distinguish …

Determination Of Β-Lactams By Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry With Quechers In Goat Milk, Wang Shuaishuai, Zheng Xiaoping, Meng Jin, He Yabin

Food and Machinery

A method was developed for simultaneous determination of 8 β-lactams in goat milk by QuEChERS-ultra performance liquid chromatography-tandem mass spectrometry (UPLC—MS/MS). The milk was extracted with acetonitrile, purified with C₁₈ and PSA sorbent and separated by an ACQUITY UPLC BEH C₁₈ column using water (containing 0.1% formic acid) and acetonitrile as mobile phase. The mass spectrometric acquisitions were carried out by means of multiple reaction monitoring (MRM) in positive ionization mode. The linear relation of eight β-lactams was good and the correlation coefficient was more than 0.986. The recovery rates of the target analyte were between 83.8%～95.4%. The …

Studies On Antifreezing Of Silver Carp Enzymatic-Hydrolysates In Frozen Surimi, Li Xianghong, Liu Zhongxiang, Deng Haiping, Liu Yongle, Yu Jian, Wang Faxiang, Wang Jianhui

Food and Machinery

The application of silver carp enzymatic-hydrolysates (Protamex hydrolysates, PH and Alcalase hydrolysates, AH) in frozen surimi was studied, with an untreated mince (CTRL) and the effects of sucrose–sorbitol on the frozen surimi as the comparison. Amino acid composition and amino acid nitrogen analysis showed that PH had higher contents of Asp, Lys and free amino acids (P<0.05). Relative molecular weight distribution results indicated that PH had more fractions of high molecular weights. Textural analysis of frozen surimi demonstrated that after 4 weeks frozen, gel strength and hardness of 2% PH and sucrose-sorbitol added group increased. Elasticity of all the samples was slightly lower. And under the frozen condition, all samples’ color was less affected. Scanning electron microscope (SEM) results displayed that protein aggregation of 2% PH and sucrose-sorbitol added groups were less, and the microstructures were less porous and more homogeneous. The surfaces of CTRL and 8% AH added groups showed obvious holes. This study indicates that PH can help to maintain quality of frozen surimi, and provides preliminary evidence for development of a possible new generation cryoprotectans using silver carp hydrolysates.

Optimization On Conditions Of Debittering Of Clarified Pommelo Juice By D101 Resin, Tang Hui, Zhong Ruimin, Xiao Zijun

Food and Machinery

The debittering conditions of pommelo juice were improved and optimized by D101 macroporous resin. The single-factor experiments and orthogonal experiments were evaluated by debittering rate of naringin and limonlids, the loss rate of Vc and the sensory evaluation, and were studied with various factors, including different amount of resin, debittering temperature, debittering time, pH value and so on. The results of best debitterize conditions by D101 macroporous resin were as follows: the resin usage was 1.7%, adsorption time was 18 min, adsorption temperature was 30 ℃ and juice's pH was 3.5. Under these conditions, the debittering rate of pommelo juice …

Understanding Perceptions Of Genetically Modified Food Among Natural Food Shoppers In Southern Nevada, Christian Murua-Aceves

UNLV Theses, Dissertations, Professional Papers, and Capstones

Today, 85% of corn, 93% of soybeans, and 88% of cotton in the U.S. are genetically modified (GM). Using laboratory methods, genes from one species, such as a plant, can be transferred to an unrelated species, such as an animal. Genetically modified crops may lead to higher yields, have improved food quality, texture, and nutritional value, and have an increased shelf life.

Despite these promising benefits, the potential health risks relating to the consumption of GM food remain inadequately assessed. Genetically modified food is not subjected to rigorous safety testing, such as epidemiologic studies, to identify potential health risks. Two …

Structural Evaluation Of Peanut Protein Isolates During Oxidation By Ftir, Ye Lin, Liao Yu, Zhao Mouming

Food and Machinery

Peanut protein isolates (PPI) was oxidized by peroxyl radicals derived from 2,2'-azobis (2-amidinopropane) dihydrochloride (AAPH) and the secondary structure of oxidized PPI were evaluated. Structural changes of PPI were elucidated using Fourier transform infrared spectroscopy (FTIR). Fourier deconvolution combined with iterative curve fitting was used to analyze the amide I of FTIR. After deconvolved amide I FTIR bands, ten major bands associated with conformation of proteins were distinctly observed. Changes in the bands at 1 618 cm^-1 and 1 682 cm^-1, which arise from the aggregated intermolecular β-sheets, indicated that protein aggregation occurred during PPI oxidation. Quantitative …

Screening Of Facultative Anaerobic Bacteria From Luzhou-Flavor Daqu And Determination Of Its Volatile Constituents, Ming Hongmei, Yu Huan, Zhou Jian, Guo Zhi, Xu Defu, Yao Xia

Food and Machinery

The facultative anaerobic bacteria in Luzhou-flavor Daqu were isolated and screened to study the species distribution of this kind of bacteria in the fermentation environment of Daqu. Then, the screened bacteria were further researched for the formation ability of the flavor components and their volatile constituents in order to improve the quality of Daqu. Through separation and purification of microorganism in the samples of Daqu by Candle jar method, 9 facultative anaerobic bacteria were obtained. Among them, the one which was coded as X₃ provided with the prominent formation ability of the flavor components and was assigned as Corynebacterium …

Titratable Acidity And Antioxidant Activities Of Fermented Tofu Whey, Liu Li, Li Li

Food and Machinery

In order to obtain tofu coagulator of high quality, investigated the titratable acidity and antioxidant activities of the fermented tofu whey by 3 strains of Lactobacillus amylolyticus L5, L6 and Pichia amethionina Y, which were separated and purified from natural fermented tofu whey, with the single, double and three strains as starters. The results indicated that both of the Lactobacillus were able to grow and produce acid in the tofu whey, the titratable acidity of fermented tofu whey by L6 for 60 h reached 65.11 ^oT at the temperature of 35 ℃, displaying a better capacity in producing acids, …

Study On Properties Of Cross-Linking Hydroxypropylated Waxy Maize Starch, Cao Yu, He Shaokai, Tian Yingliang, Sun Chen, Guo Zhenfu

Food and Machinery

Cross-linking hydroxypropylated waxy maize starches with different DS and MS were prepared by using sodium hydroxide as a catalyst, propylene oxide as an ether reagent, sodium sulfate as a swelling inhibitor, and sodium trimetaphosphate (STMP) as a cross-linking reagent. The properties such as acid resistance, salt resistance, transparencies, and freeze-thaw stability were also studied. The result showed that：the anti-acid stability, anti-salt stability, paste transparency and freeze-thaw stability of cross-linking hydroxypropyl compound modified waxy corn starches were effect by the degree of cross-linking and hydroxypropylation. The hydroxypropylation can improve the anti-acid stability, anti-salt stability and freeze-thaw stability of starches, and cross-linking …

Determination Of Release Behaviour Of Flue-Cured Tobacco By Simulated Pyrolysis Technology, Chen Yaoqi, Hong Yuan, Zeng Lingjie, Xie Wenyan, Luo Changrong

Food and Machinery

In order to investigate the heating-release behaviour of heated tobacco products, powdered Virginia tobaccos were decomposed at the temperature of 150, 200, 250, 300, 350 and 400 ℃ by pyrolytic technology respectively. It was shown that total volatiles increased with the increasing heating temperature. Compared with burned tobacco, only 5 percent of nicotine was released at 200 ℃, while 62% and 82% at 200 and 250 ℃ respectively. The heating temperature had obvious effects on the release of nicotyrine, myosmine, cotinine and 2,3'-dipyridyl. The content of nicotyrine reached the highest level at 350 ℃, up to 15.68% of the released …

Preparation Of Corn Gluten Hydrolysate With Anti-Oxidative Activity By Synergistic Action Of Alcalase And Flavourzyme, Jin Duxin, Liu Xiaolan, Zheng Xiqun

Food and Machinery

Corn protein hydrolysates of high concentration were prepared by optimizing the hydrolyzing conditions of alcalase and flavourzyme respectively. Both of which were applied synergistically to hydrolyze corn gluten to obtain antioxidative corn protein hydrolysates. The results showed that the optimal hydrolysis by Alcalase was obtained at 50 ℃, pH 7.7 and E/S of 2% (V/m) for reaction time of 75 minutes, and under the optimized conditions, DPPH radical scavenging activity and reducing power of the hydrolysate were 74.34% and 0.984 respectively; the optimal hydrolysis by Flavourzyme was reacted at 53 ℃, pH 6.4 and E/S of 5% (m/m) for reaction …

Effect Of Compound Hydrocolloids On Quality Of Beef Meat Fillet, Su Bo, Nie Qianzhong, Shi Xiuqing

Food and Machinery

In order to detect the effects of compound hydrocolloids made of carrageenan, locust bean gum, guar gum on the quality of beef meat fillet, two alternative adding modes (dry powder / hydrocolloids) were studied. Results showed that dry powder addition of compound hydrocolloids could dramatically enhance the hardness, water-holding capacity and gel strength of produced beef meat fillet. The differences between these two adding modes concerning these quality parameters proved to be significant (P＜0.05). By adopting the Design of Mixture Experiments, an optimized proportion of the compound hydrocolloids among these three were: carrageenan 59%，locust bean gum 22%，guar gum 19%, and …

Study On Enzyme Screening Of Rice Immune Active Peptide, Wang Lu, Chen Yuehua, Xu Zhou, We Nli, Bu Hanping, Cheng Yunhui

Food and Machinery

The hydrolysis processes of rice protein by had been studied 9 proteinases including Neutrase, Acalase 2.4 L, Papain, Pepsin, Trypsin, Flavourzyme, Acid protease, Protamex and Bromelain, and the immune activities of 9 protein hydrolysate had been considered. The results showed that Trypsin can be used as the optimum hydrolytic enzymes for the preparation of rice immune active peptide whose value-added index (stimulating index, SI) to mice macrophage (RAW264.7) is 1.597 (1 000 μg/mL); the enzymatic hydrolysis had the highest percentage of components with relative molecular mass <1 000, to 74.11%.

Studies On Prokaryotic Expression Conditions Of Peanut Allergen Ara H 2.02, Cai Qin, Zhang Wenju, Chen Qin

Food and Machinery

The recombinant protein was induced by transforming recombinant plasmid pET-32a (+)-Ara h 2.02 into Rosetta (DE3)，and identified by SDS—PAGE and Western Blotting. The results showed that the molecule weight of His-Ara h 2.02 fusion protein was about 38 kDa. At the same time, effect of IPTG concentration, shaking speed, induced temperature and time on the production of soluble recombinant protein were determined. The best conditions were as followed, the IPTG concentration was 0.3 mmol/L, the shaking speed was 220 r/min, the induction temperature was 37 ℃and the induction time was two hours, respectively.

Influents Of Gas On Degradation Of Chitosan With Swirling Cavitation, Yang Feng, Liu Ting, Huang Yongchun, Ren Xiane

Food and Machinery

In the present work, degradation of chitosan with swirling cavitation was investigated to strengthen the effect of degradation, reduce the molecular weight of chitosan and expand the range of application. Different operating parameters such as initial concentration, initial pH, solution temperature, outlet pressure, treatment time and the method of ventilate was investigate on the degradation of chitosan. And different gas such as air, oxygen and nitrogen was used to compare the effect of gas on the effect of cavitation. The results show that: Air has an obvious influence on the degradation of chitosan on the different reaction condition, and the …

Influence Of Properties And Microstructure By Different Pretreatment Of Cotton Seed Hull Enzyme Solution, Hou Lifen, Sun Xiangyang, Ding Changhe

Food and Machinery

With cotton seed hull as raw material, the influence was studied about the enzymatic properties and microstructure of cottonseed hull by four pretreatment methods of the dilute acid, acid pretreatment after alkali, alkali and alkaline H₂O₂. The results showed that the lignin content of cotton seed hull by the pretreatment method of alkaline H₂O₂ was decreased by 67.5%; the rate of xylan extraction about enzymatic hydrolysis for 12 hours was 21.4%; and more Xylobiose was obtained; at the same time, the microscopic structure appeared clear and loose.

Effect Of Vacuum Curing And Dry Curing On Quality Change Of Dry-Smoked Meat During Processing, Luo Qingwen, Liu Chengguo, Zhou Hui, Lou Aihua, Zhong Yiru

Food and Machinery

The change rule of smoked meat quality during vacuum curing (VC)and dry curing(DC) were studied. Two kinds of smoked meat during different processing stages were compared on the water content, salt content, sodium nitrite residue, microbiological indicator, color and volatile compounds. The results showed that: the water content of VC and DC samples decreased 16.5% and 20.5%, respectively. While salt content of that rise to 5.9% and 5.2%, respectively. The L* of VC is 2.1% higher than that of DC. The a* of VC is 12.2% lower than that of DC, the b* is no big difference between them. The …

Effects Of Infrared Drying On Properties Of Sesame, Zhang Lixia, Zhang Xun, Sun Jiajia, Huang Jinian

Food and Machinery

The sesame was dried by infrared ray, and the sesame oil was extracted with solvent. The effect of infrared drying time (constant temperature of 100 ℃) and temperature (constant time of 15 min) on the moisture content, germination rate, the volatile gas composition of sesame seeds and the acid value, peroxide value of sesame oil was investigated. The results showed that, when the infrared drying time is between 10~25 min or drying temperature between 70～130 ℃, the moisture content of the sesame seeds have reached the safety of water. Infrared drying has some damaging effects on germination rate of sesame …