风味酱鸭加工工艺优化

[目的]优化风味酱鸭的加工工艺。[方法]以鸭腿为原料,选取腌制时间、煮制时间、葡萄糖添加量和酱油添加量进行单因素试验,在此基础上采用正交试验优化,研究各自变量及其交互作用对风味酱鸭风味的影响,并对其工艺参数进行优化。[结果]风味酱鸭的最佳加工工艺条件为：腌制时间12h、煮制时间70min、葡萄糖添加量2．O％、酱油添加量30ml／kg（均以鸭腿的重量计）。在此工艺条件下,酱鸭腿风味口感较好。[结论]该研究可为风味酱鸭的工业化生产提供理论指导。     

酱油中的氯化钠测定的能力验证结果与分析

[目的]通过参加酱油中的氯化钠测定能力验证,进一步总结经验,提高实验室检测水平.[方法]比较《酱油卫生标准的分析方法》(GB/T 5009.39-2003)中直接沉淀法和《食品中氯化钠的测定》(GB/T 12457-2008)中电位滴定法的优缺点,选择直接沉淀法进行检测.[结果]样品中氯化钠含量为184.0 g/L,实验室间Z比分数为0.66,能力验证结果为满意.[结论]在此次酱油中的氯化钠能力验证中,通过对方法的比较进行实验室内部质量控制,严格按照方法操作,控制取样等关键点,获得满意结果.     

The USDA trypsin inhibitor study. I. Background,objectives, and procedural details

Short-term feeding studies have shown that raw soy flour and purified trypsin inhibitors (TI) cause pancreatic hypertrophy and hyperplasia in certain monogastric animals. Prolonged exposure to high levels of TI in raw soy ultimately leads to pancreatic nodular hyperplasia and acinar cell adenoma in rats exposed to low levels of pancreatic carcinogens. Such change has been observed even in the absence of any exposure to known carcinogens. These results emphasized the need for chronic (2 yr) feeding trials which would clearly reveal dose response relationships of alterations in pancreatic pathology to dietary TI and possible interactions with dietary protein and fat.Here we report on the objectives and designs of the first phase of the USDA TI Study, including composition of diets, preparation, and analyses of test substances. To provide the requisite TI and protein levels, raw and heated defatted soy flours, soy protein isolates, and lactic casein were used. The interrelationship of dietary level of TI (93–1270 mg/100 g diet) and that of protein (10%, 20%, and 30%) to pancreatic function and pathology will be reported in the following three papers. Both serial and chronic sacrifice regimes, respectively, were employed with 26 diets and 40 weaning male Wistar rats per dietary group.The mention of firm names or trade products does not imply that they are endorsed or recommended by the U.S. Department of Agriculture over other firms or similar products not mentioned.     

The USDA trypsin inhibitor study. II. Timed related biochemical changes in the pancreas of rats

A total of 600 rats was distributed equally among 15 diets formulated from mixtures of raw and toasted soy flour and casein so as to provide 5 different levels of trypsin inhibitor (TI) at 3 levels of protein (10%, 20%, and 30%). Animals were sacrificed at the end of 6 months and at 3-month intervals thereafter over a period of 22 months. Increases in the secretory activity of the pancreas, as measured by trypsin and chymotrypsin activities in the pancreas and small intestines, were associated with increasingly higher levels of TI and protein but did not change appreciably with time. Hypertrophy and hyperplasia of the pancreas, as reflected by changes in pancreas weight and RNA and DNA content, developed at an early stage (6 months) and were likewise positively correlated with the levels of TI and protein in the diet. Although the hypertrophic response remained unchanged with time, hyperplasia became more pronounced as the period of exposure to TI was prolonged. The peptide test confirmed the stimulatory effect of TI on the pancreas, but some functional impairment was noted in those animals which had been fed raw soy flour for 18 months of or longer. The appearance of nodules on the pancreas was observed by gross inspection after 15 months, and these became larger and more numerous with time. The incidence of nodules was highly correlated with the level of TI in the diet and was highest when the diet contained 20% protein.     

紫甘蓝花青素智能指示膜的制备及其在牛乳新鲜度监测中应用

为研究不同紫甘蓝花青素含量对大豆分离蛋白基智能指示膜性能的影响,提高指示膜的综合包装性能,考察指示膜对巴氏杀菌乳新鲜度的监测效果。以大豆分离蛋白（Soy Protein Isolate,SPI）为原料,添加紫甘蓝花青素（Purple Cabbage Anthocyanins,PCA）制备指示膜,对其结构、热性能、机械性能、色度及其稳定性和pH敏感性进行表征和分析,并将指示膜应用于巴氏杀菌乳新鲜度监测中。结果表明：相对于大豆分离蛋白膜,含有4%（质量分数紫甘蓝花青素的指示膜,拉伸强度从2.46 MPa增加到3.77 MPa,断裂伸长率从105%增加到131%;与标准白的色差从21.23增加到52.88,指示膜明度降低,色度偏黄绿色,结晶温度比SPI膜升高了3 ℃。指示膜的色度在常温下5 d内不出现可视性色差,但pH敏感性强。将指示膜应用于巴氏杀菌乳新鲜度监测中,指示膜的颜色随着牛乳变质由绿变红,指示膜与原始膜的色差变化与巴氏杀菌乳的pH值变化呈相反趋势,且色差可视。因此,该指示膜具有监测巴氏杀菌乳腐败过程的潜力,应用前景广阔。     

利用生物技术开发酱油渣试验

以假丝酵母与黑曲霉为出发菌种,经工艺条件的筛选与优化,研制出蛋白质含量明显增加,且有较高酶活的饲料蛋白质添加剂。     

豆浆处理工艺改善内酯豆腐的质构特性

豆浆的粒子大小可以通过一定的处理工艺加以改变,从而提高内酯豆腐质构特点。该文研究了胶体磨磨齿间隙(10~30μm)、超声波功率强度(1~3 W/g)、匀浆机转速(1 000~5 000 r/min)对内酯豆腐质构特点的影响。结果表明胶体磨处理能显著(p0.05)提高内酯豆腐的弹性和内聚性。但在间隙为10μm的情况下,长时间研磨会降低硬度。在不同超声波功率强度条件下,内酯豆腐的硬度和弹性都是先上升后下降。超声波处理会显著(p0.05)降低内酯豆腐的内聚性。匀浆处理对内酯豆腐的质构特点均产生先上升后下降的影响。通过Topsis法进行多指标综合评价,得出较好的豆浆处理工艺是匀浆处理1 000 r/min处理8 min。粒径分析结果证明处理工艺能降低豆浆粒径大小。豆浆处理工艺可以改善内酯豆腐的质构特点,从而满足人们的不同需求。     

不同复水方式对大豆拉丝蛋白复水品质的影响及动力学模型构建

大豆拉丝蛋白（textured fibril soy protein,TFSP）是经螺杆挤压技术生产的具有类似肉纤维结构的高密度植物蛋白,复水处理后常被用来加工仿真肉产品。为了提高TFSP的复水品质,该研究在40 ℃条件下,采用不同的超声功率和NaHCO₃浓度对TFSP 进行复水处理,通过对复水动力学模型的构建预测其复水过程,并探究不同复水方式对TFSP理化性质及微观结构的影响。结果显示,与纯水组相比,TFSP复水至120 min时,500 W超声组的最终含水率提高27.14 %、复水时间缩短20 min;2.000 %NaHCO₃组的最终含水率提高23.41 %,复水时间无明显变化。Weibull模型可较好的拟合对照组（R²≥0.993 3）、超声组（R²≥0.990 5）和NaHCO₃组（R²≥0.986 7）的TFSP复水过程。超声和NaHCO₃处理均略微降低了复水TFSP的色泽,但提高了其持水能力和不易流动水含量。复水TFSP的硬度、咀嚼性、组织化度发生变化,弹性无明显差异。400 W超声组的组织化度最大,较对照组提高41.80 %;0.250 %NaHCO₃组的硬度达到最小,较对照组减小54.17 %。扫描电镜（scanning electron microscope,SEM）观察显示,超声和NaHCO₃处理改变了复水TFSP的微观结构,使其孔隙增大,加速水分传输速率,提高了容纳水的能力。因此,若以最大组织化度为主要评价指标,应选择超声辅助TFSP复水,而若以最低硬度为主要评价指标,则选择NaHCO₃辅助复水效果为好。该研究结果可为采用不同复水方式、开发不同品质的TFSP制品提供理论基础和参考。     

木瓜蛋白酶凝固大豆蛋白质机理

本文研究了木瓜蛋白酶对豆浆的凝固机理，通过酶反应过程中游离氨基和蛋白质表面疏水性的变化，初步确定酶法凝固的机理是在酶的作用下，蛋白质暴露了一些疏水基,并立即通过蛋白质分子间的疏水相互作用结合成凝胶。     

75%咪唑乙烟酸可溶粉大豆田苗前封闭除草田间药效及安全性试验

田间试验结果表明,75%咪唑乙烟酸可溶粉用药量为5.5~11 g/667 m2,喷液量为30 kg/667 m2,此用药量和喷液量用于大豆田苗前封闭除草,可有效控制大豆田整个生育期杂草。特别对苣荬菜、藜、苋、刺菜有显著防效,对稗草、铁苋菜有理想的防除和控制作用。对大豆安全无药害产生,对大豆后期生长和产量不但无不良影响,而且在株高等方面还有一定的促进作用。