黄原胶流变特性的应用

黄原胶具有独特的流变特性,其粘度值随不同剪切速率发生明显变化,是典型的假塑性流体,其粘度值随浓度的升高而增大,成线性关系,pH为4-10时,黄原胶溶液粘度值不受影响,大于80℃的加热温度可使黄原胶溶液粘度降低,黄原胶与羧甲基纤维素钠混合具有增粘效应。     

卡拉胶、瓜儿豆胶与果胶复配在酸奶中的应用

首先确定卡拉胶、瓜儿豆胶、果胶在酸奶中的用量范围,研究了三种胶体与变性淀粉复配做为酸奶增稠剂.通过感官评定与流变仪分析相结合,获得最适合酸奶发酵体系的胶体配比组合,果胶0.25‰,卡拉胶0.15‰,瓜儿豆胶0.55‰,变性淀粉4‰.     

硅窗气调包装与普通气调包装对茶树菇贮藏品质的影响

为了提高茶树菇的贮藏品质,通过采用硅窗气调包装与普通气调包装对茶树菇进行贮藏,研究硅窗气调包装与普通气调包装的茶树菇总糖含量、原果胶含量、可溶性果胶含量、蛋白质含量及总氨基酸含量、游离氨基酸含量和粗纤维含量的变化情况。结果表明：与普通气调包装相比,硅窗气调包装贮藏的茶树菇总糖含量、原果胶含量、蛋白质含量及总氨基酸含量下降较慢,而粗纤维含量、可溶性果胶含量及游离氨基酸含量增加较少。由此得出,硅窗气调包装是一种贮藏茶树菇比较好的方法,用这一方法贮藏的茶树菇保持了较多的糖类和蛋白质,保持了较好的口感和相应的脆度,具有更好的贮藏品质。     

Doses response of dietary viscosity on digestibility and faecal characteristics of striped catfish (Pangasionodon hypophthalmus)

The study analysed the dose–response relationship between dietary viscosity and nutrient digestibility, faecal waste characteristics in striped catfish and the long‐term impacts of viscosity on performance of striped catfish. This was done in two experiments: Exp.1 lasted 29 days, in which six dietary viscosity levels were created by including different amount of guar gum (GG; 0, 0.25, 0.5, 1.0, 2.0 or 3.0 g/kg) and Exp.2 lasted 60 days and assessed the long‐term effects of three dietary GG levels (0, 0.5 and 3.0 g/kg) were checked. In Exp.1, digestibility of nutrients (except crude fat) decreased linearly with dietary viscosity. With increasing viscosity, removal efficiency of faeces from the water reduced linearly, whereas the total amount of faeces produced and the fraction of big‐sized faecal particles (>2 mm). increased linearly. In Exp.1, viscosity did not affect performance. However, in Exp.2, the GG inclusion level of 3.0 g/kg (1.72 cP for the viscosity) affected fish performance. In conclusion, the best strategy for faecal waste management in striped catfish by dietary viscosity is to keep it as low as possible in the diet.     

白及胶复合保鲜液对芒果的保鲜作用研究

[目的]自制白及胶复合保鲜液用于芒果的保鲜,以解决新鲜芒果贮藏和运输难的问题。[方法]以白及胶、金银花-槐米-广藿香制得的天然抑菌剂、纳米二氧化钛为原料制得白及胶复合保鲜液,并研究其对芒果的保鲜作用。[结果]白及胶复合保鲜液处理的芒果各项测定指标均优于国内同类产品鲜立克保鲜液,其能有效延缓芒果的失重、转黄、腐烂,降低芒果呼吸强度,抑制可滴定酸、Vc、可溶性总固形物含量的下降,明显抑制病害,降低腐烂指数,保持果实的良好品质,延长果实的贮藏寿命。[结论]白及胶复合保鲜液的原辅料均来源于天然生物,无毒、无害、可食用、安全可靠、易于生物降解、不污染环境,具有广阔的应用前景。     

低酰基/高酰基复合酸性结冷胶凝胶的凝胶特性研究

利用应力松弛模式研究了低酰基结冷胶(LA)/高酰基结冷胶(HA)质量配比、基体总浓度、pH值对低酰基/高酰基复合酸性结冷胶凝胶(L/H-GLG)凝胶特性的影响。结果表明,复合酸性凝胶的应力松弛行为可用Peleg模型进行拟合,平衡模量EA可用来表征复合酸性凝胶的凝胶强度。LA/HA质量配比、pH值和基体浓度对复合酸性结冷胶凝胶的凝胶特性影响显著。随着LA/HA质量配比的增加,EA和k1均表现出先增大、后减小的变化规律,在LA/HA质量配比为50∶50时获得最大值,说明此时LA和HA形成了互穿网络。随着pH值的增加,复合酸性结冷胶凝胶的EA呈现了先增大、后减小的变化趋势,pH值为3时最大。结冷胶总浓度越高,EA越大。相对于高酰基结冷胶,低酰基结冷胶对酸更为敏感。此外,模拟胃液酸环境时,以pH值为2的酸液浸泡可以对复合凝胶的结构与凝胶特性产生影响。     

亚麻胶浸提工艺研究

以水为浸提溶剂,以亚麻籽为原料,研究了溶剂倍量、浸提温度和浸提时间对产胶率的影响,得出了产胶率随这些因素变化的规律,确定了试验条件下的最适溶剂倍量为16、最适浸提温度为80℃、最佳浸提时间为5h。     

松脂加工中松节油损失的探讨

松脂加工中松节油的回收率在 60 %～ 70 % ,松节油损失严重。本文对松脂加工过程的松节油损失进行了探讨 ,提供了减少松节油损失的改进措施和建议     

植物胶体与植物蛋白复配对午餐肉品质特性的影响

为改善传统午餐肉易软烂，质构松散的特性，以传统配方午餐肉为对照，选用魔芋胶、大豆分离蛋白及海藻酸钠为辅料进行复配优化，探究植物胶体与植物蛋白对午餐肉质构和感官品质的影响。结果表明，优化组的最佳配比为：魔芋胶添加量0.200%，大豆分离蛋白添加量2.687%，海藻酸钠添加量0.173%。优化组煮制前后的硬度、黏附性、弹性、咀嚼性均显著高于对照组（P＜0.05）。与对照组相比，优化组午餐肉煮制前后的组织形态和总体接受度评分均更高。研究表明植物胶体和植物蛋白的添加明显提高了午餐肉煮制前后的质构特性和感官品质。     

Correlating the fineness and residual gum content of degummed hemp fibres

It is well known residual gum exists in degummed or retted hemp fibres. Gum removal results in improvement in fibre fineness and the properties of the resultant hemp yarns. However, it is not known what correlation if any exists between the residual gum content in retted hemp fibres and the fibre fineness, described in terms of fibre width in this paper. This study examined the mean width and coefficient of variation (CV) of fibre width of seventeen chemically retted hemp samples with reference to residual gum content. The mean and CV of fibre width were obtained from an Optical fibre diameter analyser (OFDA 100). The linear regression analysis results show that the mean fibre width is directly proportional to the residual gum content. A slightly weaker linear correlation also exists between the coefficient of variation of fibre width and the residual gum content. The strong linear co-relation between the mean of fibre width and the residual gum content is a significant outcome, since testing for fibre width using the OFDA is a much simpler and quicker process than testing the residual gum content. Scanning Electron Microscopy (SEM) reinforces the OFDA findings. SEM micrographs show a flat ribbon like fibre cross-section hence the term “fibre width” is used instead of fibre diameter. Spectral differences in the untreated dry decorticated skin samples and chemically treated and subsequently carded samples indicate delignification. The peaks at 1370 cm⁻¹, 1325 cm⁻¹, 1733 cm⁻¹, and 1600 cm⁻¹ attributed to lignin in the untreated samples are missing from the spectra of the treated samples. The spectra of the treated samples are more amine-dominated with some of the OH character lost.