免疫传感器在食品安全检测中的应用

免疫传感器具有较好的灵敏度和特异性，操作简便、响应速度快，在食品安全检测中应用前景广阔，本文简单介绍了免疫传感器的组成及其基本原理，综述了免疫传感器在食品安全检测中的应用进展，并对其在食品检测领域中的应用前景进行展望。     

ACID AND THERMAL RESISTANCE OF A SALMONELLA ENTERITIDIS STRAIN INVOLVED IN SEVERAL FOODBORNE OUTBREAKS

Acid and thermal resistances of a Salmonella enteritidis strain involved in several foodborne outbreaks in southern Brazil were compared with other two Salmonella serovars. Strains were cultivated in Nutrient Broth supplemented with 1% glucose for acid adaptation, and then cells were exposed to different pH and temperatures. Survivors were enumerated and cellular proteins were analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). S. enteritidis presented better acid adaptation than S. typhimurium and S. bredeney after exposure to pH 3.5 and 4.0, but all serovars demonstrated a similar behavior at pH 4.5. At 52C, nonadapted and acid-adapted S. bredeney presented enhanced survivor rates when compared to the other serovars, although acid adaptation protected S. enteritidis. At 56C and 60C, nonadapted and acid-adapted S. enteritidis was more thermally resistant than other serovars. Differences in protein profiles of nonadapted and acid-adapted cells of all serovars were observed by SDS-PAGE. S. enteritidis demonstrated greater acid adaptation and thermal resistance after acid adaptation than other serovars.

PRACTICAL APPLICATIONS

These results could be related to the frequent involvement of this strain with salmonellosis in southern Brazil. Information on the thermal resistance of pathogenic microorganisms is an important step toward the optimization of the thermal processing of foods. Underestimation of thermal resistance increases the risk that a sufficient portion of an initial pathogen population may persist after thermal treatments, which could result in a foodborne outbreak.     

纳米食品及其制备技术的探讨

在简要介绍纳米技术、纳米食品基本概念的基础上，分析了纳米食品制备技术的可行性和应用领域，并就纳米固醇、纳米富硒食品两个应用案例进行讨论，为纳米食品的进一步开发提供了参考性技术路线。     

食品病原微生物快速检测技术研究进展

随着食品工业的迅速发展,研究和建立食品病原快速检测方法以加强对食品卫生安全的监测越来越受到各国的重视.对目前一些具有良好发展空间的食品微生物检测技术的原理和应用进行了综述,包括分子生物学技术、免疫技术、代谢技术、生物传感器、蛋白质指纹图谱技术等.     

食品中病原微生物快速检测方法研究进展

食品中病原微生物是影响食品安全性的最主要生物因素。本文综述了食品中病原微生物的快速检测方法研究进展，并对微生物培养法、免疫学方法和核酸分子杂交等现优检测方法进行了比较和评述。     

A COMPREHENSIVE FORMULA FOR THE ACCEPTANCE OF FOOD TEXTURE, AND ITS GENERALIZATION TO OVERALL FOOD ACCEPTANCE

A survey is made of factors contributing to food texture (atoms, molecules, structure, mechanics) together with factors leading to food texture acceptance (stimulus-response, preferences), and a formula is developed for the relations among all these factors. An extension to general acceptance, involving all sensory quality factors, is also made.     

食品包装安全应急准备响应机制的建立和实施

简述了当前食品包装的安全现状,初步分析食品包装的安全性问题产生的原因和对人类健康的危害,依据IS022000:2005(食品安全管理体系)对食品包装安全的应急准备响应机制进行阐述.提出针对食品链上相关组织的针对食品包装安全的应急准备与响应的系统模式,并在此基础上提出实施流程和要则.     

OPTIMIZATION OF IMMOBILIZATION PROCESS ON CRAB SHELL CHITOSAN AND ITS APPLICATION IN FOOD PROCESSING

Optimization of immobilization process on crab shell chitosan was carried out. The chitosan purified from the crab shell was used as the matrix for the immobilization of α-galactosidase. The prepared matrix was activated with glutaraldehyde at different concentrations and different time intervals and coupling time was determined. Immobilization of α-galactosidase on crab shell chitosan resulted in 72% immobilization yield. The parameters like the effect of pH, temperature, thermal stability and storage stability were determined. The study revealed that immobilized enzyme shows better thermal and storage stability than the free enzyme. The performance of the free and immobilized α-galactosidase was tested in continuous stirred batch reactor to hydrolyze raffinose family oligosaccharides in soymilk. The oligosaccharide content of the soymilk was reduced by 77% in continuous reaction by immobilized α-galactosidase.

PRACTICAL APPLICATIONS

Chitosan used for the immobilization of α-galactosidase offers several advantages for enzyme immobilization and it contains all characteristic features for use as industrial material. Immobilization of one of the industrial important enzyme α-galactosidase, as it has many potential application in hydrolyzing raffinose series of oligosaccharides. The hydrolyzed soymilk after processing by immobilized α-galactosidase is free from flatus-inducing factors like raffinose and stachyose. It can be used as an alternative means for cow's milk for lactose intolerance, particularly among individuals in developing countries. As chitosan used is from the crustacean waste from the crab shell, the production and utilization of chitosan provides an economical alternative means of crustacean shell waste disposal sought worldwide.     

THE PURIFICATION OF PROTEASE FROM COWSLIP (PRIMULA VERIS) AND ITS USE IN FOOD PROCESSING

Proteases perform very important functions and are used in different objectives as in vitro and in vivo. In recent years, proteases have been used for clinical, pharmaceutical and industrial applications. Most of these proteases are obtained from animal sources. News of diseases passing over from animals to human (severe acute respiratory syndrome [SARS], mad cow) has created suspicion of contamination in animal food and its product. Therefore, a new vegetal protease source for use in the food industry was studied. Ammonium sulfate fractionation and CM‐sephadex ion exchange chromatography were used in the purification of the enzyme. The purified enzyme has an optimum pH of 7.0 and its optimum temperature was 70C. The V_max and K_m values determined by Lineweaver–Burk graphics were 0.44 mg/mL.min and 40 mM, respectively. The purification degree was determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS‐PAGE ). The native molecular weight of the enzyme was 46 kDa using a gel filtration chromatograph. SDS‐PAGE results show that the enzyme has two subunits, which have protease activity at 32 and 14 kD. It was investigated whether the purified and characterized protease enzyme would cause to congeal milk or could produce digestion of chicken and cow meat. The results showed that the protease enzyme can be used for industrial production.     

IN VITRO ANTIOXIDANT AND ANTICANCER ACTIVITIES OF EXTRACTS FROM A FERMENTED FOOD

Solvent extracts were prepared from Manda Enzyme®, one of the fermented health foods, and their activities of radical scavenging and cancer cell growth inhibition were evaluated. Manda Enzyme® was extracted with 55% ethanol, and then fractionated into n‐hexane, chloroform, ethyl acetate, methanol‐soluble and methanol‐insoluble fractions. The antioxidant activities were in the order chloroform > ethyl acetate > other fractions and of each fraction were positively related to the amount of total phenolics and the intensity of brown color. The cancer cell growth inhibitory activities were in the order n‐hexane > chloroform > other fractions. Proliferation of HRT‐18, HCT‐48 and HepG2 human cancer cells was inhibited by the treatment of the n‐hexane fraction of Manda Enzyme® at a concentration of 400 μg/mL to the extent of 75, 89 and 90%, respectively. From these results, it is considered that Manda Enzyme® has chemically different ingredients showing strong antioxidant and anticancer activity in vitro.     

固相萃取HPLC法同时测定食品中乙基麦芽酚和香兰素

建立了食品中乙基麦芽酚和香兰素的高效液相色谱测定法。方法采用C18（5μm，4．6mm×250mm i．d）反相色谱柱，流动相为乙腈和0．02mol/L磷酸二氢钠溶液，流速1．0mL/min，检测波长276nm，柱温30℃，进样量20μL。该方法的检出限0．5μg/g-2．0μg/g，测定低限饮料1mg/L,-4mg/L，固态食品为5μg/g-20μg/g，线性范围2．0mg／L～100mg/L，加标回收率97．1％～88．7％，相对标准偏差为4．27％～6．74％（n=9）。     

AN INTRODUCTION TO MASS SPECTROMETRY AND ITS APPLICATION IN THE ANALYSIS OF BEER,WINE, WHISKY AND FOOD

Mass spectrometry is a powerful analytical technique by which different chemical compounds can be identified, and valuable information gained as to their chemical structure. Both qualitative and quantitative data can be obtained and the instrumentation can be used on a stand-alone basis, or as a detector for a chromatographic system such as gas chromatography or high performance liquid chromatography. This paper provides a basic knowledge for analysts and brewers alike not familiar with the technique. To illustrate its utility, a number of examples are given for the analysis of food, beverages and contaminant components in raw materials and product. These include the identification of phenolic flavour components in whisky and beer, fatty acids in pizza, diethylene glycol confirmation in wine and contaminants identified from beer packaging materials.     

食品及包装材料中双酚A及其环氧衍生物残留分析的研究进展

双酚A及其环氧衍生物在食品包装材料中的迁移可能会造成人类和野生动物的内分泌系统、免疫系统、生殖系统和神经系统出现异常,是导致食品污染的重要途径之一.综述食品及包装材料中双酚A及其环氧衍生物的残留分析方法,并对未来食品中双酚A及其环氧衍生物的控制进行展望.     

大豆多肽的生理功能及在食品工业中应用前景探讨

以大豆分离蛋白为原料经现代生物技术加工研制大豆多肽和大豆多肽的营养生理功能厦加工特性进行综述，并进一步探讨了大豆多肽作为一种新型的食品功能因子在一些食品开发中的应用前景。     

PREPARATION OF CLOVE BUDS DEODORIZED AQUEOUS EXTRACT (CDAE) AND EVALUATION OF ITS POTENTIAL TO IMPROVE OXIDATIVE STABILITY OF CHICKEN MEATBALLS IN COMPARISON TO SYNTHETIC AND NATURAL FOOD ANTIOXIDANTS

ABSTRACT

Antioxidative properties of prepared clove buds deodorized aqueous extract (CDAE) in chicken meatballs are studied. Total phenolic and flavonoid contents were found to be 271.9 ± 12.0 mg gallic acid equivalent per gram and 161.6 ± 7.7 mg rutin equivalent per gram CDAE, respectively. Chicken meatball samples were: (1) C (control, i.e., without CDAE), and those supplemented with 200 ppm of; (2) T1 (CDAE); (3) T2 (ascorbic acid); and (4) T3 (butylated hydroxyanisole [BHA] : butylated hydroxytoluene [BHT] = 1:1). Oxidative stability was assessed by measuring peroxide value (PV) and 2‐thiobarbituric acid reactive substances (TBARS) besides determination of color and sensory acceptability, over 12 days of chilled storage (8 ± 1C). All the treated samples showed higher induction period as well as lower PV and TBARS values than “C” throughout 12 days of storage (*P < 0.05). Color analysis showed that CDAE greatly improved redness of meatballs as compared with ascorbic acid and BHA‐BHT (*P < 0.05). Meanwhile, hedonic test indicated that treatment T1 did not affect sensory acceptability of chicken meatballs for all the tested attributes (color, aroma, taste, texture and overall acceptance) (*P > 0.05) up to comparable extent with T2 and T3.

PRACTICAL APPLICATIONS

The study provides a valuable method for the preparation of meatballs by replacing harmful synthetic antioxidants with natural ones with promising antioxidant and shelf‐life potential besides maintaining sensory attributes. This adaptation may result in massively enhanced consumption of these meatballs with disease‐preventive and health‐promoting effects. The main hurdle in commercialization of spicy meatballs is the pungent smell of spices as well as use of toxic organic solvents for extraction. The problem has been overcome by developing a method for the preparation of deodorized extracts in aqueous medium, which may significantly enhance the commercialization potential of meatballs and meatball‐based functional foods.