葡萄酒抗氧化的研究进展

氧化问题是造成衰老和心血管疾病的主要原因。葡萄酒作为抗氧化良品在一定程度上可以抗衰老和减少疾病发生。该文介绍近几年,葡萄酒的最新研究进展。从抗氧化能力研究方法、抗氧化机制、葡萄酒不同成分的体外抗氧化作用、生物体(动物和人)内的抗氧化作用4个方面介绍了葡萄酒抗氧化方面的研究进展。最后综合分析当前研究情况,并展望葡萄酒抗氧化研究的发展方向。     

Simultaneous determination of three pesticides and their metabolites in unprocessed foods using ultraperformance liquid chromatography-tandem mass spectrometry

We have developed a rapid, multi-compound analytical method for measuring residues of the pesticides thiamethoxam and its metabolite, clothianidin; fipronil and its three metabolites, fipronil sulfone, fipronil sulfide, and fipronil desulfinyl; and pyraclostrobin in unprocessed foods (rice, corn, cucumbers, tomatoes, apples, and bananas) by ultra-performance liquid chromatography coupled to tandem mass spectrometry. Acetonitrile was used as the extraction solvent, and an octadecylsilane-dispersive SPE was used to clean up the analytes, which were then separated through a UPLC HSS T3 column connected to a tandem mass spectrometer via an electrospray ionisation source. The linearity of this method for the target analytes was excellent (R² ≥0.990) in the concentration range of 5–1000 μg kg^–1. The average recoveries of the seven compounds at concentrations of 10, 100, and 1000 μg kg^–1 from six spiked matrix samples ranged from 73.6 to 110.6%, all with RSD values of ≤19.7%. The limit of quantification was 10 μg kg^–1. The method validated the effectiveness of the method for routine monitoring the residue of these pesticides and their metabolites in foods.     

牛乳中主要过敏原组分的分离纯化及鉴定

目的:分离纯化并鉴定牛乳中引起过敏反应的主要致敏组分。方法:采用聚丙烯酰胺凝胶电泳(SDS- PAGE)分析了脱脂乳和乳清的蛋白组分,用饱和硫酸铵分段盐析-DEAE离子交换柱层析纯化过敏原蛋白,脱脂乳和乳清蛋白皮下注射Balb/c小鼠获得高效价特异性IgE抗血清用于免疫印迹分析。结果:免疫印迹分析显示β-乳球蛋白(β-Lg)是引起牛乳过敏的主要过敏原,建立了牛乳过敏小鼠模型。结论:明确了牛乳过敏的主要过敏组分,对牛乳过敏症的诊断治疗以及无过敏原牛乳的制备提供了实验依据。     

冷冻型乳酸发酵豆奶的研制

以豆浆为培养基 ,接种保加利亚乳杆菌和嗜热链球菌工作发酵剂 ,混合发酵 ,再将富含活性菌的发酵豆乳按比例替代冰淇淋中的乳制品 ,经老化、凝冻、速冻的方法制成冷冻型发酵豆奶。     

燕麦高纤食品基料在挂面中的应用

把燕麦高纤食品基料应用在挂面中,研究了燕麦高纤食品基料添加量为10％、20％、30％以及加入添加剂时,对燕麦高纤挂面质量指标、感官品质、加工性能的影响。     

韩式面酱的加工工艺

通过韩式面酱与甜面酱加工原料、设备、配方及加工工艺进行比较，结果表明：韩式面酱在口感、质地上优于甜面酱。     

发酵肉中有益菌的分离筛选研究

以MRS培养基和番茄汁琼脂培养基为基础培养基,从自然发酵的咸肉、咸鱼、香肠中分离得到五个菌株,均为球状菌。经过进一步测试表明:五个菌株在pH5.0左右或低于5.0时生长良好;五株菌在2%～6%的NaCl浓度内生长较适宜,其中有两株菌在10%NaCl的环境中仍能生长,五株菌的生长适宜温度范围在30℃～40℃之间,但在35℃培养时生长最好。基本都能符合肉品发酵剂的要求。     

基质固相分散在食品安全分析中的应用

MSPD作为一种崭新的SPE技术，对半固体、固体样品中目标成分分析具有独一无二的特性，国外已将此法广泛的应用于食品中药物残留、污染物和有害成分分析。本文介绍了MSPD在食品安全分析中应用，并且讨论了MSPD在样品处理中的理论和实践。     

Quantitative detection method for Roundup Ready soybean in food using duplex real‐time PCR MGB chemistry

BACKGROUND: Methodologies that enable the detection of genetically modified organisms (GMOs) (authorized and non‐authorized) in food and feed strongly influence the potential for adequate updating and implementation of legislation together with labeling requirements. Quantitative polymerase chain reaction (qPCR) systems were designed to boost the sensitivity and specificity on the identification of GMOs in highly degraded DNA samples; however, such testing will become economically difficult to cope with due to increasing numbers of approved genetically modified (GM) lines. Multiplexing approaches are therefore in development to provide cost‐efficient solution. RESULTS: Construct‐specific primers and probe were developed for quantitative analysis of Roundup Ready ^® soybean (RRS) event glyphosate‐tolerant soybean (GTS) 40‐3‐2. The lectin gene (Le1) was used as a reference gene, and its specificity was verified. RRS‐ and Le1‐specific quantitative real‐time PCR (qRTPCR) were optimized in a duplex platform that has been validated with respect to limit of detection (LOD) and limit of quantification (LOQ), as well as accuracy. The analysis of model processed food samples showed that the degradation of DNA has no adverse or little effects on the performance of quantification assay. CONCLUSION: In this study, a duplex qRTPCR using TaqMan minor groove binder‐non‐fluorescent quencher (MGB‐NFQ) chemistry was developed for specific detection and quantification of RRS event GTS 40‐3‐2 that can be used for practical monitoring in processed food products. Copyright © 2010 Society of Chemical Industry