HACCP体系在果蔬保鲜处理过程中的应用

为了确保果蔬食用的安全性、有效延长保鲜期,通过对果蔬保鲜处理过程中的各个环节可能潜在的危害进行生物性、化学性和物理性分析得出关键控制点。应用HACCP七个步骤确定果蔬保鲜过程中的关键控制点及关键限值,制定相应纠偏措施和关键控制点的监控方法,有效地预防了潜在危害对果蔬的污染,最大程度地确保产品的安全与卫生,从而为HACCP在果蔬加工生产中的应用提供了有力的参考依据。     

乳源性金黄色葡萄球菌肠毒素A的间接ELISA检测方法建立

从乳品中筛选出金黄色葡萄球菌,并对其所产的肠毒素进行分离纯化。制备出金黄色葡萄球菌肠毒素的特异性抗血清,建立金黄色葡萄球菌肠毒素A特异性血清间接ELISA方法。结果表明,最佳抗原包被浓度为10μg/mL,抗体最佳稀释倍数为1︰1 600,抗血清效价达到1︰3 200。通过建立此检测方法可以为乳源金黄色葡萄球菌肠毒素的检验提供依据。     

凡纳滨对虾酶解产物过敏原消减效果的评价

采用木瓜蛋白酶分解凡纳滨对虾的蛋白质,以消减其中的蛋白质过敏原;应用豚鼠全身过敏反应和离体回肠平滑肌过敏性收缩实验模型,对该蛋白酶酶解产物的致敏性进行评价。结果显示,虾蛋白和虾肉经木瓜蛋白酶水解后,其酶解产物所致的全身过敏反应明显减轻(与虾蛋白组和虾肉组比较,0.01相似文献   

MP-AES法测定皮革和纺织品中可萃取重金属含量

采用微波等离子体原子发射光谱法(MP-AES)测定皮革和纺织品中9种可萃取重金属的含量。样品经过人工酸性汗液萃取,MP-AES测定其As、Cd、Co、Cr、Cu、Hg、Ni、Pb、Sb的可萃取含量。结果表明:方法检出限在0.004～0.330mg/kg之间,加标回收率在89%～108%之间,相对标准偏差小于1.5%。该方法操作简便,可实现多种元素同时测定,检出限低、线性范围宽并具有良好的准确度和精密度,与ICP-OES法具有极佳的吻合性,适用于皮革和纺织品中可萃取重金属含量的检测。     

液质联用分析常见植物油甘油三酯

采用高效液相色谱-串联飞行时间质谱法分析了常见植物油如大豆油、芝麻油、花生油、特级初榨橄榄油、葵花籽油、玉米油、油茶籽油、棉籽油和菜籽油的甘油三酯。结果显示每种植物油甘油三酯的种类和含量均不相同。该方法测定甘油三酯有效可行,可为甘油三酯结构信息研究及油脂掺伪鉴别提供基础支持。     

Hydroxypropylated microcrystalline pea starch: optimisation,functional characterisation

Pea starch (PS) appears to be very attractive for the peculiar physicochemical characteristics, which is used for the vermicelli, film‐forming material due to the high amylose content. The aim of this study was to optimise the hydroxypropylation technology parameters of the microcrystalline pea starch based on pea starch as a raw material, hydrochloric acid as an hydrolysis reagent, epoxy propane as an etherisation reagent by the Box–Behnken method. The thermal properties of hydroxypropylated microcrystalline pea starch were characterised by the thermogravimetric analyser and differential scanning calorimeter, respectively. Through the analysis of Design‐Expert software, the regression model and corresponding variances were obtained. In this case, the determination coefficient (R²) was 0.9631. This implied that 96.31% of the variation could be explained by the regression model. The best reaction conditions for preparing the hydroxypropylated microcrystalline pea starch were as follows: reaction temperature 40 °C, reaction time 16 h, amount of epoxy propane 14%, amount of sodium hydroxide 1.2% and amount of anhydrous sodium sulphate 12%. After the microcrystalline pea starch was hydroxypropylated, its peak temperature, melting enthalpy, temperature range of the endothermic peak increased, but its the thermal stability, onset temperature decreased.     

Influences of superheated steaming and roasting on the quality and antioxidant activity of cooked sweet potatoes

Roasted sweet potato is a popular food because of the attractive aroma produced by the Maillard reaction. However, the roasting process may lead to charred skin. Cooking with superheated (saturated) steam provides a solution to this problem. As the results show, when comparing sweet potatoes cooked by superheated steam, and those roasted for 40 min, respectively, the degree of gelatinisation could reach as high as 95% with only 140 °C superheated steam, while roasting required temperatures up to 240 °C. Moreover, in appearance, the skins of the sweet potatoes cooked using superheated steam were not charred like the roasted ones. However, sweet potatoes roasted at 240 °C for 60 min had the highest overall sensory score. When comparing the antioxidant activity, the sweet potatoes cooked by superheated steam had the highest content of total phenol and flavonoids, the best scavenging ability of 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) and the highest ferric‐reducing ability of plasma (FRAP).     

Effect of thermal treatment on the characteristic properties of loach peptide

The effects of thermal treatment on the changes in the colour, the molecular weight distribution, amino acid profiles and the overall antioxidant activities of loach peptide were investigated. When the thermal temperature was rising, the browning was enhanced. The contents of free amino acids Gly, Arg, Thr and Tyr were increased, whereas those of Asp, Ser, Met, Cys, Trp and Lys were decreased. The scavenging activities (1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical scavenging activity, the oxygen radical absorbance capacity (ORAC) and the reducing power of loach peptides after different thermal treatments were lower than those of the control, whereas the Cu²⁺ chelating activity was higher (except from the sample treated at 100 °C, 20 min). The heat treatment at 121 °C, 15 min was shown to be the best thermal processing, as it caused the least loss in radical scavenging activity and showed relatively higher Cu²⁺ chelating activity.     

浅析珠三角广绣产品的营销策略

通过对广绣产品营销现状的了解,进行SWOT分析及市场定位,提出将广绣归为奢侈品消费的基本概念,结合广绣产品的特色总结出适宜珠三角地区的广绣产品营销策略.     

我国电力行业安全防护服的现状及发展

分析我国电力行业安全防护服的发展现状、相关标准和存在的问题。介绍了我国电力行业安全防护服的分类,包括防电弧工作服、带电作业屏蔽服、高压静电防护服、焊接服和高可视警示服等;从防护意识、防护性能和防护标准等方面,分析了我国电力行业安全防护服的应用现状及存在问题。认为:我国应在防护服的功能性、舒适性、外观、款式等方面加强研发,并尽快制定相关标准,为电力行业人员提供可靠的安全防护。