油脂预乳化提高大豆拉丝蛋白素食香肠品质

为了提高大豆拉丝蛋白(Textured Fibril Soy Protein,TFSP)素食香肠的品质,该研究将油脂预乳化工艺应用于TFSP素食香肠的加工,利用响应面试验设计优化了预乳化工艺条件,采用质构分析仪测定分析了产品的质构特性,并进行了感官评价。结果表明优化后的最佳预乳化工艺条件为菜籽油含量445g/L、大豆分离蛋白浓度105g/L、乳化机剪切速率9.0×103r/min。与对照组相比,此条件下制作的预乳化-TFSP素食香肠的凝胶强度、硬度和咀嚼性分别提高了约1倍、10%和26%,且产品口感鲜嫩、富有汁液感,感官评价得分显著提高。采用激光共聚焦显微镜观察分析了不同工艺制作的TFSP素食香肠在煮制前后微观结构的变化,结果发现油脂预乳化工艺可大大提高乳化油脂的稳定性和在香肠凝胶基质中的均匀分布,从而使乳化油脂的‘填充作用’得以发挥,不仅增强了TFSP素食香肠的保水保油能力,降低了蒸煮损失率,而且对香肠的质构和感官特性产生了重要影响。因此油脂预乳化工艺是一种辅助提高素食香肠整体品质行之有效的方法。     

Effects of natural feeding stimulants and glutamic acid supplementation on the feed intake,growth performance and digestive enzyme activities of red sea bream (Pagrus major) fed fish meal‐free soy protein concentrate (SPC)‐based diet

Two experiments were conducted for red sea bream (Pagrus major). In experiment 1, the optimum level of glutamic acid and natural feeding stimulants to enhance feed intake were determined and found that glutamic acid level of 0.5% and fish meat hydrolysate (FMH) were effective. In experiment 2, fish were fed with soy protein concentrate (SPC)‐based diet with synthetic feeding stimulants (Basal diet), the Basal diet with FMH (FMH diet), the FMH diet with glutamic acid (FMHG diet) and with fish meal diet (FM diet) as a control until satiation for 8 weeks. Feed intake of FMHG‐fed fish was significantly higher than others (p < 0.05). Specific growth rate and the feed conversion ratio of FMHG were comparable to those of FM‐fed fish (p > 0.05). Relative visceral fat ratio and crude lipid content of any SPC‐based diet‐fed fish tended to be lower than those of FM diet‐fed fish. There were no significant differences in trypsin and lipase activities hepatopancreas among treatments. SPC can be utilized as a sole protein source in a diet for red sea bream. The lower growth performance in SPC‐based diet‐ fed fish was not due to poor digestive enzyme secretion but could be associated with lipid utilization disorder.     

电子鼻和电子舌单独与联合检测掺大豆蛋白或淀粉的鸡肉糜

为实现掺杂掺假鸡肉的快速、客观评价，该研究利用电子鼻和电子舌联合检测技术对掺杂鸡肉糜进行快速检测，通过对采集的数据进行主成分分析和偏最小二乘法分析，所得结果表明，采用主成分分析，电子鼻和电子舌联合检测掺大豆蛋白鸡肉糜和掺淀粉鸡肉糜的主成分总贡献率分别为99.8%和99.1%；采用偏最小二乘法分析，电子鼻和电子舌联合检测鸡肉糜中掺杂大豆蛋白含量的预测值与真实值之间的决定系数为0.992，均方根误差为2.8%；联合检测鸡肉糜中掺杂淀粉含量的预测值与真实值之间的决定系数为0.996，均方根误差为2.4%。表明电子鼻和电子舌联合检测对鸡肉糜的掺杂情况具有良好的区分和预测能力，并且是一种有效、高精度的肉类掺假检测方法。     

Substitution of fish meal by soybean meal in diets for juvenile marbled spinefoot,Siganus rivulatus

The present work was performed to assess whether soybean meal (SBM) could replace fish meal (FM) as a source of dietary protein in diets of the marine herbivore Siganus rivulatus. Five iso-nitrogenous (40% protein) and iso-energetic (14 MJ/Kg) diets were prepared with SBM replacing fish meal at 0%, 25%, 50%, 75%, and 100% dietary protein. A 60-day feeding trial was conducted with 240 juvenile S. rivulatus (initial body mass 1.74 ± 0.03 g). Survival, growth, feed, and protein efficiency and hematological parameters were assessed. Growth correlated negatively with increase in dietary SBM. All production parameters measured were negatively affected at all levels of SBM inclusion. There were no effects on total or differential blood counts, hemoglobin, or plasma protein, but hematocrit values were negatively correlated with SBM addition. Results suggest that total replacement of FM by SBM without adding other supplements is not recommended, even for an herbivorous marine fish such as S. rivulatus.     

SPI凝胶颗粒制备及其Pickering高内相乳液特性研究

制备了大豆分离蛋白（Soy protein isolate，SPI）凝胶颗粒，并使用该颗粒制备了稳定的Pickering高内相乳液。通过粒径和ζ 电位测定、冷冻扫描电镜和光学显微镜观察以及外观分析，以流变特性为指标，对SPI凝胶颗粒和Pickering高内相乳液特性进行研究。结果表明，SPI凝胶颗粒的粒径和ζ 电位随pH值的变化而变化，当SPI凝胶颗粒pH值为4.0～5.0时，临近SPI等电点，ζ 电位的绝对值最小，此时凝胶颗粒相互聚集，不能成功制备稳定的高内相乳液。在pH值为 9.0时，大豆分离蛋白凝胶颗粒紧密结合在一起，呈凝胶网络状结构。在碱性条件下，蛋白质质量分数为1.00%、内相体积分数为78%～82%时，可以制备稳定的Pickering高内相乳液。通过增加内相体积分数，使大豆分离蛋白凝胶颗粒稳定的Pickering乳液体系分布更加均匀，不易发生聚集，形成更加致密稳定的多孔结构，且具有更强的弹性凝胶乳液特性。     

卵磷脂桶混助剂的特性及其在防治稻飞虱中对氟啶虫胺腈的协同增效作用

为明确新型卵磷脂类桶混助剂“融透”的特性，采用透射电镜和激光粒度分析仪表征了其物理性质，并通过室内生物测定和田间药效试验测定了其在防治稻飞虱中对氟啶虫胺腈的协同增效作用。结果表明，“融透”中含有圆形脂质体，Z平均粒径为129.5 nm。室内生物测定结果表明，“融透”可使氟啶虫胺腈对褐飞虱的毒力增加1.67倍。田间药效试验表明，“融透”可使氟啶虫胺腈对稻飞虱的防效提高9.04%~41.77%；当氟啶虫胺腈减量40%时，添加“融透”的处理对稻飞虱的防效与未添加“融透”的常量组相当。研究结果表明，卵磷脂桶混助剂“融透”可以通过形成脂质体提高药剂的利用率，从而达到增效的作用。     

Comparative effect of advanced soy products or corn protein concentrate with porcine meal on growth,body composition,and distal intestine histology of Florida pompano,Trachinotus carolinus

The present study was designed to investigate the effects of diets containing advanced soy products (enzyme‐treated soy and fermented soy) or corn protein concentrate (CPC) in combination with porcine meal (PM) to completely replace poultry byproduct meal (PBM) on growth performance, body composition, and distal intestine histology of Florida pompano, Trachinotus carolinus. Four experimental diets were formulated to be isonitrogenous and isolipidic, to contain 400 g/kg crude protein and 80 g/kg lipid. A reference diet (PBM diet [PBMD]) contained 150 g/kg PBM and 495 g/kg soybean meal (SBM), and three test diets were formulated replacing PBM with 15 g/kg of CPC (CPC diet [CPCD]) or replacing all SBM and PBM with 535 g/kg fermented soy (fermented soybean meal diet [FSBMD]) or 451.3 g/kg enzyme‐treated soy (enzyme‐treated soybean meal diet [ESBMD]). All three test diets were supplemented with 38 g/kg of PM. Diets were fed based on a percentage of bodyweight adjusted after sampling the fish every 2 weeks to triplicate groups of Florida pompano juveniles (mean weight 8.06 ± 0.22 g). After 8 weeks of feeding, fish fed CPCD and ESBMD performed equally well in terms of final body weight, thermal growth coefficient, and percentage weight gain in comparison to fish fed PBMD. In all cases, feeding FSBMD resulted in poor feed conversion and lower feed intake compared to other treatments. Protein retention efficiency, whole‐body proximate composition, phosphorus, sulfur, potassium, magnesium, calcium, sodium, and zinc contents were not significantly influenced by the dietary treatments. The results obtained in the present histological study showed no significant differences in the thickness of serous layer, muscular layer, and submucosal layer of the intestine among treatments. Fish fed CPCD showed a significant widening of the lamina propria with an increase of cellular infiltration and higher presence of goblet cells compared to other dietary treatment. Based on these results, 451 g/kg ESBM or combination of 150 g/kg of CPC and 495 g/kg SBM supplemented with 38 g/kg PM can be utilized to develop a practical diet for juvenile Florida pompano without impacting growth, nutritive parameters, and several distal intestine health parameters.     

α和α'亚基缺失对大豆分离蛋白乳化特性的影响

为了探究β-伴大豆球蛋白(7S)中α和α′亚基缺失对大豆分离蛋白乳化特性的影响,该文以东农47(对照)和3种不同蛋白亚基缺失型(α缺失、α′缺失以及α、α′缺失)大豆为原料提取大豆分离蛋白(SoyProteinIsolate,SPI),通过十二烷基磺酸钠聚丙烯酰胺凝胶电泳(Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis,SDS-PAGE)技术分析其亚基组成,然后制备乳状液并测定乳化活性指数(Emulsifying Activity Index,EAI)、ζ-电位、粒径、微观结构、稳定动力学指数(Turbiscan Stability Index,TSI)及界面蛋白吸附量。结果表明:α′亚基缺失型SPI乳状液乳化活性指数最大,为87.59 m2/g;ζ-电位绝对值最大,为47.7 mV;粒径最小,为2.223μm;显微结构显示其分子最小且分布最均匀,稳定动力学指数最小;界面蛋白吸附量最大,为31.40%。4种不同SPI乳状液的稳定性结果由大到小为α′亚基缺失型、东农47、α亚基缺失型、α和α′亚基缺失型。研究结果可为高乳化性大豆蛋白系列产品的开发应用提供理论支撑和技术支持。     

大豆卵磷脂分离纯化工艺的研究进展

大豆卵磷脂是以大豆油脚为原料提炼的卵磷脂,含有胆碱、维生素、矿物质、亚麻酸及次亚麻酸等成分,具有多种生理功能,并在许多领域内得到了广泛的应用。然而由于技术原因,高纯度卵磷脂的生产仍存在一定的技术障碍,阻碍了其在医药等领域的推广应用。为此,对近年来大豆卵磷脂分离纯化工艺的研究进展做一简要综述和分析,以期为高纯度大豆卵磷脂的研究与应用提供参考。