大豆蛋白胶枫木刨花板热压工艺研究

为了解决甲醛等有害物质的释放问题,使用大豆蛋白胶作为热压枫木刨花板的无甲醛胶粘剂,研究了刨花板的热压工艺.在实验室条件下,通过单因素试验分别分析了热压温度、热压时间、施胶量和密度对枫木刨花板内结合强度及表面结合强度的影响;并通过响应面设计得出最佳试验参数.结果表明,大豆蛋白胶可以用于枫木刨花板的制造,其最佳工艺参数为:热压温度180℃,热压时间27.5min,施胶量15.7%,密度780kg/m3.在此条件下,压制的板材性能均达到GB/T4897.1-2003对在干燥状态下使用的普通用板要求.     

大豆异黄酮甙元提取工艺的研究

采用先酸水解、后碱水解的方法从大豆中提取游离型大豆异黄酮甙元成分，并通过单因素实验和正交实验确定了碱水解的最佳提取工艺条件．结果表明，碱水解的最佳条件是：pH8．75、温度50℃、提取时间90min，此条件下大豆异黄酮甙元的提取率为44．3％，粗提品纯度为19．9％．     

酱油增香发酵用酵母的纯化和生长特性分析

对酵母菌种进行了分离纯化,绘制出分离纯化后的酵母菌种的生长曲线。通过设计正交试验,确定出各菌种的最适生长条件。实验结果表明,T酵母的最适生长条件为:培养基中食盐添加的质量分数为0.07,温度28℃,pH值5,Ca2+浓度10-3mol·L-1;鲁氏酵母的最适生长条件为:培养基中食盐添加的质量分数为0.08,温度32℃,pH值5.5,Ca2+浓度10-4mol·L-1。     

空气/水界面上大豆11S球蛋白吸附膜的膨胀特性

采用轴对称滴形分析法检测了不同体相蛋白含量和pH值条件下，空气／水界面上大豆11S球蛋白吸附膜的表面膨胀特征参数随吸附时间的变化．结果表明：随着吸附时间的延长，吸附膜的表面膨胀模量增大，相角减小；膨胀弹性明显高于膨胀粘性，因此，从流变学的角度分析，空气／水界面上大豆11S球蛋白吸附膜的粘弹性实际上是弹性的；表面膨胀模量随体相蛋白浓度的增加而增大，受pH值的影响更为明显．     

混合菌种发酵生产酱油的工艺研究

利用米曲霉(Aspergillus oryzae)和黑曲霉(Aspergillus niger)混合接种,并在制曲后期混合添加嗜盐片球菌(Pediococus halophilus)和高渗酵母进行多菌种发酵生产酱油实验研究。结果表明,混合发酵的菌种最佳培养时间为36～40h,最佳发酵温度为45～48℃。米曲霉和黑曲霉的接种比为90%∶10%时,全氮利用率提高13.2%,氨基酸生成率提高6.8%。将成熟曲拌以10%的食盐水,在pH值为6.5的环境下,混合添加嗜盐片球菌和高渗酵母参与发酵可以提高酱油产品中的醇类含量和酸类含量,改进酱油的风味。     

常用食品强化铁锌对儿童铁锌缺乏的效果观察

已证明铁和锌在膳食中供给不足，造成这二种元系缺乏所引起的各种疾病在儿童中所占的比率分别为５９％和５０％。选用日常生活中不可缺少的酱油作为载体，用人体易吸收的葡萄糖酸亚铁，葡萄糖酸锌作为强化剂制成强化酱油，缺铁、锌儿童各４０例服用一个月以后，结果表明：血清铁、锌明显上升，统计学分析有显著性差异（ｐ〈０．０５）。     

豆乳粉生产过程中的关键控制点确定与危害分析

就豆乳生产中原料进货，贮存、产品生产和出场合格检验，产区卫生，员工培训等方面进行了危害分析，对豆乳生产中常见质量问题的主要原因，并提出了相应的预防措施和控制方法。     

广州地区市售酱油污染黄曲霉毒素和花椒毒素的抽样调查

目的:对2000年广州地区部分市售品牌酱油以及12所高校的35间食堂、餐厅、饮食店等使用的酱油进行了污染黄曲霉毒素B1(AFB1)、花椒毒素(XAT)情况进行抽样调查,以了解当年该地区市售酱油的污染情况.方法:采用国际通用的高效薄层层析法(HPTLC)进行检测.结果:AFT阳性(AFB1≥5μg/kg)检出率为24%～33%,污染量从5μg/kg到25μg/kg,最高的高出国家标准4倍;样品中XAT阳性(XAT≥5μg/kg)检出占20%.结论:当年该地区部分市售酱油存在着黄曲霉毒素及花椒毒素的污染.     

Effects of soy isoflavone extracts on the growth of estrogen-dependent human breast cancer (MCF-7) tumors implanted in ovariectomized nude mice

In this study, we explored the effects of soy isoflavone extracts on the growth of estrogen-dependent human breast cancer (MCF-7) tumors implanted in ovariectomized athymic mice. The ovariectomized athymic mice were implanted with MCF-7 cells. They were fed with low, moderate and high doses of soy isoflavone extracts, at dietary concentrations of 6.25, 12.5 and 25 g/kg, respectively. The expression of ki-67 was detected by immunohistochemistry. The pS ₂ expression in tumors was analyzed by real-time PCR. Estrogen level in the serum was measured by chemiluminescence enzyme immunoassay. Compared with the control group, dietary soy isoflavone extracts had a significant stimulatory effect on MCF-7 tumor growth in mice (P < 0.05). The ki-67 and pS ₂ mRNA expressions in tumors were significantly increased by 6.25 and 12.5 g/kg dose of soy isoflavone extracts (P < 0.05). And, estrogen level in serum of 6.25 and 12.5 g/kg dose groups was higher than that of control group (P > 0.05). In conclusion, in the tested dietary concentration range soy isoflavone extracts had a stimulatory effect on tumor growth. 6.25 and 12.5 g/kg doses of soy isoflavone extracts can increase the cell proliferation in tumors and induce estrogen-responsive pS2 expression. Supported by National Natural Science Foundation of China (Grant No. 30572133)     

Rheological Properties of Soy Protein Isolate and Polyurethane in the PAN/DMSO Solution

The rheological properties of soy protein isolate (SPI) and polyurethane (PU) in the PAN/DMSO solution were investigated in this study. The results showed that all these solutions possessed pseudo-plastic solution properties. There are opposite effects of SPI and PU in the PAN/DMSO solution. Their apparent viscosity, degree of non-Newtonian fluid, and extent of structuralization of blend system increase with the addition of SPI, whereas, all of these decrease with the addition of PU. Moreover, the rheologic...