暗色等刺参(Isostichopus fuscus)营养成分分析

目的测定暗色等刺参的主要营养成分,评价其营养价值。方法分别采用凯氏定氮法、高温灼烧法、亚甲基蓝比色法测定海参中的粗蛋白、灰分、海参多糖含量,采用氨基酸自动分析仪测定氨基酸组成,采用电感耦合等离子体质谱法测定常量、微量无机元素。结果暗色等刺参的海参多糖含量为8.04%,蛋白质含量高达83.35%,且氨基酸组成丰富,其中甘氨酸、谷氨酸、丙氨酸含量相对较高。暗色等刺参富含人体所需的多种矿物质元素,常量元素中Ca、Mg含量较高,微量元素中Fe、Zn的含量较高。结论暗色等刺参富含蛋白质、海参多糖以及人体所需的无机元素,具有较高的食用价值和开发利用前景。     

均匀试验法优化褐藻胶-乳清分离蛋白可食性膜的工艺

目的制备褐藻胶-乳清分离蛋白可食性膜幵对其工艺条件迚行优化。方法以褐藻胶(sodium alginate,SA)和乳清分离蛋白(whey protein isolate,WPI)为主要原料,甘油为增塑剂制得可食性膜。以溶胶温度、溶胶时间、SA和WPI浓度、钙化时间、钙离子浓度、甘油浓度、超声时间为因素迚行均匀试验,考察指标为溶胶黏度、膜的厚度、透光率、拉伸强度。结果可食性膜性能受WPI浓度、溶胶温度、溶胶时间、钙化时间、超声时间的影响较大,基本不受SA浓度、钙离子浓度和甘油浓度影响,所确定的最佳配比及工艺条件为:SA浓度1.1%、WPI浓度5.5%、溶胶温度65℃、溶胶时间105 min、钙化时间12 min,钙离子浓度1.1%、甘油浓度3.4%和超声时间30min。结论该工艺条件下制备的褐藻胶-乳清分离蛋白可食性膜性能较好,需迚一步验证SA浓度、钙离子浓度和甘油浓度的影响。     

4种烹饪方式对草鱼肉中孔雀石绿、结晶紫及其代谢物消减的影响

目的探讨煮、蒸、炸和微波等4种烹饪方式对草鱼肉中孔雀石绿、结晶紫及其代谢物消减的影响。方法在空白草鱼肉中添加孔雀石绿、隐色孔雀石绿、结晶紫和隐色结晶紫后,分别用4种方式烹饪,采用高效液相色谱串联质谱测定药物的含量。结果结果表明:经过炸、微波、煮和蒸等烹饪方法处理后,鱼肉中的药物浓度分别降低了79.8%～93.7%、69.4%～91.2%、72.0%～86.2%和69.6%～77.8%。相同的烹饪方式,原药的消减速度均高于代谢物,药物的消减速率顺序为:炸微波煮蒸。结论高温加热能促进孔雀石绿、结晶紫及其代谢产物的消减。     

6种鲤科鱼肌肉脂肪的脂肪酸组成比较及相关性分析

为研究鲤科鱼肌肉脂肪中脂肪酸组成及含量的差异,以鳙鱼、缩骨鳙鱼、翘嘴红鲌、鲢鱼、青鱼和脆肉鲩6种鲤科鱼为研究对象,利用气相色谱-质谱联用仪(GC-MS)测定其肌肉脂肪的脂肪酸组成及含量,再采用IBM SPSS Statistics 22. 0对各脂肪酸组成进行相关性分析和聚类分析。结果表明:6种鲤科鱼肌肉脂肪的饱和脂肪酸(SFA)含量为23. 83%～36. 35%,单不饱和脂肪酸(MUFA)含量为30. 87%～54. 34%,多不饱和脂肪酸(PUFA)含量为17. 92%～35. 07%,C20∶5+C22∶6(EPA+DHA)含量为0. 58%～16. 27%;主要组分间的相关性分析结果表明,C18∶0与EPA呈极显著正相关(相关系数r=0. 900～1. 000),EPA与DHA呈显著正相关(r=0. 800～0. 899),C18∶1与DHA呈极显著负相关,与EPA呈显著负相关;聚类分析将6种鲤科鱼分为2组,第一组为缩骨鳙鱼、翘嘴红鲌、青鱼和脆肉鲩,第二组为鳙鱼和鲢鱼。6种鲤科鱼肌肉脂肪中均含有较多的不饱和脂肪酸,具有较高的营养价值和开发利用潜力。     

Comparison of simplex and duplex real-time PCR for the quantification of GMO in maize and soybean

This paper focuses on the determination of the GMO content of maize and soybean samples using real-time PCR, comparing simplex and duplex PCR. The total DNA content of samples was determined by amplifying part of a maize gene encoding a lipid transfer protein, or part of a soybean lectin gene. The transgenic DNA was quantified by amplifying part of the CaMV 35S promoter. The importance of preparation and conservation of standards as well as the relevance of DNA extraction protocol on the variability of results are discussed. For the determination of low GMO content, limitation in the number of copies of the target gene to be amplified is considered. For samples with a theoretical GMO content of 1%, corresponding to the legal threshold for labelling, the value determined by duplex real-time PCR ranged from 0.85% to 1.20%. Both real-time simplex and duplex PCRs allowed identification of GMO free samples without ambiguity.     

Incorporation and optical behaviour of 4-dimethylaminazobenzene in sol-gel silica thin coatings

Various percentages of 4-dimethylaminazobenzene (dimethyl yellow, DY) have been incorporated into silica sol-gel coatings prepared from tetraethylorthosilicate and methyltriethoxysilane. The dye was entraped in the sol-gel layer maintaining its acid-basic properties. Sensitivity of coatings against pH in aqueous media was evaluated by absorption spectrophotometry for each type of samples, including one pre-treated at low temperature. The response time of coatings from acid pH to neutral conditions and vice versa allows to propose the use of this system as a pH optical sensor. On the other hand, several tests oriented to point out the behaviour of coatings during chemical attack were performed: firstly by dipping the samples in distilled water for different lengths of time and, secondly, submitting them to reiterated cycles at 60 °C in a washing machine using conventional abrasive detergent. Results obtained in both cases indicated good resistance, especially for those hybrid films prepared from tetraethylorthosilicate and methyltriethoxysilane doped with 5 wt.% DY.     

鲍鱼及其副产物综合加工利用研究进展

鲍鱼作为海珍品深受国内外广大消费者的喜爱。随着养殖技术的日益成熟和养殖产量的不断增长,中国已成为世界第一鲍鱼养殖和消费国家。为提高鲍鱼产品原料利用率和产品附加值,鲍鱼加工技术也逐渐向综合利用和高新技术方向发展。本文综述鲍鱼肉的加工利用现状（干鲍、冻鲍、鲍鱼罐头）,并对其加工工艺进行具体介绍;同时综述鲍鱼加工下脚料（内脏）及鲍鱼壳的高值化开发利用现状,并对鲍鱼综合加工与利用前景进行展望,旨在为鲍鱼的进一步开发利用提供参考。     

解淀粉芽孢杆菌发酵液保鲜冷却猪肉的效果研究

实验研究了解淀粉芽孢杆菌发酵液对冷却肉的防腐保鲜效果,对冷却肉的微生物、感官品质和理化指标3个方面进行了检测.结果显示,解淀粉芽孢杆菌发酵液处理组可将冷却肉的保质期延长6d～9d,而且效果优于Nisin.解淀粉芽孢杆菌发酵液对冷却肉中主要污染菌-假单胞菌和潜在致病菌-单增李斯特菌有较好的抑制效果.解淀粉芽孢杆菌发酵液作为冷却肉的生物防腐剂,具有广阔的应用前景.     

水产调味品中挥发性盐基氮的测定

为提高水产调味品中挥发性盐基氮测定的效率,对国标GB/T 5009.44-2003中的半微量定氮法进行了改进:用高氯酸溶液替代水来浸溶样品;用氢氧化钠溶液加消泡剂替代了氧化镁混悬液;用自动凯氏定氮仪替代半微量蒸馏装置和半微量滴定管.用改进的方法测定以市售蚝油和虾酱为基质的加标样品,回收率在98.82％～101.26％之间,相对标准偏差在0.80％以下.检测数据与GB/T 5009.44-2003中的半微量定氮法相比,无显著性差异.结果表明,改进的方法是一种简便、快捷、精确的水产调味品中挥发性盐基氮的测定方法.