保鲜处理对冷鲜鲟鱼肉特征性风味成分的影响

为明晰保鲜处理对冷鲜鲟鱼肉冷藏期间的特征性风味物质的影响。本实验利用固相微萃取—气相色谱—质谱联用(SPME-GC-MS)结合电子鼻和电子舌技术,对经微酸性氧化电解水和ε-聚赖氨酸两步法保鲜处理的冷鲜鲟鱼肉在冷藏期间的挥发性成分和滋味成分进行分析。电子鼻能够对挥发性成分从整体上进行分析,贮藏后期保鲜处理组和对照组的鲟鱼肉挥发性气味的数据集无重叠区域,差异明显。利用SPME-GC-MS定性鉴定出46种挥发性物质,主要包括醛类、酮类、烃类和醇类等物质,其中己醛、庚醛、苯甲醛、辛醛、壬醛、癸醛和2,5-辛二酮、苯乙酮、3,5-辛二烯-2-酮为保鲜处理组的主要挥发性物质,保鲜处理延缓了冷鲜鲟鱼肉腥味的产生以及鱼肉香味的下降。电子舌检测冷藏过程中鲟鱼肉的滋味物质时发现,保鲜处理组苦味、涩味、咸味均低于对照组,两组样品贮藏6 d后,在苦味、涩味、咸味、鲜味方面均呈显著差异。保鲜处理起到了减缓冷藏期间冷鲜鲟鱼肉风味物质下降的作用,为保鲜处理在冷鲜鲟鱼肉中的应用提供了一定的理论基础。     

联合分析法在混合动力汽车产品定位中的应用研究

从消费者购买决策角度出发,利用联合分析法,构建我国市场A级混合动力汽车属性与水平模型,分析消费者购买混合动力汽车时赋予不同属性的相时重要性及属性水平的效用值,并模拟产品组合市场占有率情况,从而为混合动力汽车产品定位提供依据.     

豆制品中胰蛋白酶抑制剂活性测定方法研究

利用紫外分光光度计，对豆制品中胰蛋白酶抑制剂在抑制牛胰蛋白酶活性反应前后的吸光值差异制作差值曲线，从而得出斜率与抑制剂活性之间关系的方法。并通过反复的实验对比，最终可以快速准确地测定大豆制品中胰蛋白酶抑制剂活性。     

HACCP体系在冷却肉生产中的应用

介绍了HACCP体系及其在肉制品中的应用现状,并阐述了HACCP质量管理体系在冷却肉生产加工过程中的应用。     

基于对象建模的农机产品CAPP系统设计与应用

利用对象建模技术,通过抽象与重组形成CAPP系统的一般对象模型,并把对象、关联及操作等映射成数据库表和程序实体,结合农机产品CAPP实例论述了工艺过程卡对象模型的实现流程,分析了选单等的设计重用方法。实践证明,CAPP系统开发过程中,只需开发一个编辑窗口,而非对应每一个数据表开发相应的编辑窗口。当数据表发生结构改变时可通过修改数据窗口来实现。采用这种方法,同一个选单就可以被不同的窗口所共用,使系统的开发效率大大提高,同时系统的结构也非常合理,根据作业机的主体结构相似性,可应用于各类农机制造的工艺设计过程。     

Improvement of the traditional method of ogiri production and identification of the micro-organisms associated with the fermentation process

Fermented products were developed from different proportions of melon (Citrullus vulgaris schrad) and groundnut (Arachis hypogea) seeds after a 96 hour fermentation period. Proximate analysis, carried out on both fermented and unfermented samples, indicated that only the total carbohydrate content was appreciably reduced by the fermentation process. Micro-organisms responsible for fermentation were identified by gram staining and lactophenol staining, as bacteria and fungi. Identified bacteria were of the Bacillus and Acinetobacter species while the fungi were yeasts, rhizopus and mucor. Samples containing 50–100% melon showed a decrease in pH with increasing fermentation period. Bacteria were largely responsible in samples containing up to 75% groundnuts. Sensory analysis of dried fermented products after fortification with salt, ascorbic acid and flour indicated that they were acceptable.     

Influence of temperature on the fermentation of bambara groundnut (Vigna subterranea) to produce a dawadawa-type product

Bambara groundnut (Vigna subterranea) was fermented to produce a dawadawa-type product using a starter culture of Bacillus licheniformis isolated from naturally fermenting bambara groundnut beans. Fermentation was carried out at 30 and 37 °C for four days and at 45 °C for two days. The pH of the substrate decreased after 24 hours and then rose at 30 and 37 °C but remained constant at 45 °C after the initial drop. Total titratable acidity of the fermenting beans mimicked the pH values. Proximate analyses for moisture, protein and fat of the cotyledons showed an increase in all three constituent at each of the three fermentation temperatures. At the end of fermentation, total available carbohydrate was 55%, 59% and 62% of the original value at 30, 37 and 45 °C, respectively. Fermentation of bambara groundnut at 45 °C for two days is recommended as the ideal fermentation temperature and time.     

以“猪疫情”与“猪周期”叠加致肉价波动为契机建立新时代立体生态养殖产业链

该文从2019年中国生猪和猪肉产品价格大幅波动而带动CPI快速上调的“高通胀风险”及与工业生产PPI下降的“高通缩风险”关联性,探讨了推动猪肉价格快速上涨的机制.难控性“猪疫情”、规律性“猪周期”、投机性“猪炒作”及泛化性“外贸战”是促进肉产品价格快速上涨的“启动”、“叠加”、“内讧”及“外推”四大机制,并建议以此为机...     

茶皂素的提取纯化及成品中茶皂素含量的测定

采用AB-8大孔吸附树脂对茶皂素成品进行纯化,提取标准品。利用紫外-可见分光光度计进行扫描得出茶皂素标准品在205nm处出现最大吸收峰;经香草醛-硫酸显色,最大吸收波长为435nm,在539nm处有较弱的吸收峰。用自制茶皂素纯品为标样,采用香草醛-浓硫酸显色法,绘制茶皂素定量的标准曲线,测定成品茶皂素的含量为80.9%。