BP neural network algorithm has great application value and potential in the field of food storage. In the present study, BP neural network was introduced into the quality warning model of stored wheat, and the quality prediction and influence analysis of stored wheat were carried out by recording the indoor temperature and regularly detecting elevenphysiological and biochemical indexes, such as moisture, starch and protein, based on the sampling data of stored grain in Tianjin. The simulation results showed that the data prediction method based on BP neural network has less process error and higher result accuracy, providing an effective research method for the quality prediction of stored wheat.

小麦霉变是食品仓储中常见现象,对小麦霉变过程中品质演变与微生物间的关系进行了介绍,研究在小麦储藏过程中小麦霉变时期的组成和结构、导致霉变的主要微生物种类以及霉变过程中营养成分变化.通过研究小麦霉变各个时期的颜色、气味、硬度、营养成分以及毒素含量变化情况,对淀粉酶、蛋白酶、脂氧合酶、挥发性物质等含量的变化进行论述,确定霉变对小麦品质变化的影响与微生物生长之间的关联规律,为实际生活中安全储存生产小麦提供理论依据和实际指导.

In order to definite the molecular structure and allergic characteristics of cashew nuts, the main allergic proteins were isolated and purified by organic solvent defatting, salting out, dialysis and Sephadex G-150 gel. The allergenic proteins were definitely by UV, BCA kit, SDS-PAGE and Western-Blotting. The amino acid sequence and the DNA sequence of cashew allergic protein were obtained by using the NCBI database and protein mass spectrum sequencing. The structure of cashew allergic protein was predicted by DNAstar bio-information software and circular dichroism (CD). The results showed that the Ana o 2 and Ana o 3 were the main cashew allergenic proteins with molecular weight of 33 and 17 kD. The results of CD and Protean program in DNAstar predicted that there were α-helical, β-folded regions and corner regions which was a hydrophilic protein with strong sensitization because of the β-corners and random curls were found in 54% in Ana o 2. The secondary structure had only a small amount of β-folded region and corner region, accounted for 12%, but had mainly α-helix and random coil structure. It was also hydrophilic allergic protein, and the formation of allergenic epitopes was relatively weak. This study would provide reference for further clarifying the structure of the main allergens of natural cashew nuts and exploring the sensitization mechanism of cashew nuts.

小麦仓储过程中品质会发生一系列的变化,保持其品质新鲜,控制和减缓粮食品质劣变,不用或少用化学熏蒸药剂,为消费者提供绿色放心粮食,是中国粮食仓储行业目前面临的一项紧迫任务.文章对气调储粮、温湿调控、智能监控、害虫检测、菌群检测等储粮检测方法方式进行了系统阐述分析,综述了仓储小麦品质劣变监控检测的研究进展,并结合当前存在的问题,展望了粮食仓储技术的未来发展趋势.

针对小麦仓储过程中出现的品质劣变问题,以北方实仓储藏的硬质白小麦为研究对象,通过测定仓储过程中小麦的色差、水分、脂肪、脂肪酸、淀粉含量等指标反映品质劣变程度;采用低场核磁共振成像技术(low-field nuclear magnetic resonance,LF-NMR)和差示扫描量热法(differential scanning calorimetry,DSC)可视化检测小麦仓储过程中水分传递和淀粉转变现象,寻找仓储过程中小麦水分迁移变化规律以及直链淀粉、支链淀粉的转化关系,探索小麦淀粉糊化反应.结果表明,小麦在仓储过程中色泽逐渐变暗,脂肪酸含量增加,水分、脂肪和淀粉总量减少,LF-NMR和DSC检测结果表明长期仓储小麦受环境因子影响会使其结合水的含量升高,自由水含量下降,糊化温度降低.