Determination of total dietary fibre and available carbohydrates: A rapid integrated procedure that simulates in vivo digestion

The new definition of dietary fibre introduced by Codex Alimentarius in 2008 includes resistant starch and the option to include non‐digestible oligosaccharides. Implementation of this definition required new methodology. An integrated total dietary fibre method was evaluated and accepted by AOAC International and AACC International (AOAC Methods 2009.01 and 2011.25; AACC Method 32–45.01 and 32–50.01, and recently adopted by Codex Alimentarius as a Type I Method. However, in application of the method to a diverse range of food samples and particularly food ingredients, some limitations have been identified. One of the ongoing criticisms of this method was that the time of incubation with pancreatic α‐amylase/amyloglucosidase mixture was 16 h, whereas the time for food to transit through the human small intestine was likely to be approximately 4 h. In the current work, we use an incubation time of 4 h, and have evaluated incubation conditions that yield resistant starch and dietary values in line with ileostomy results within this time frame. Problems associated with production, hydrolysis and chromatography of various oligosaccharides have been addressed resulting in a more rapid procedure that is directly applicable to all foods and food ingredients currently available.

     

多孔性交联淀粉絮凝剂的制备研究

以玉米淀粉为原料,先用a-耐高温淀粉酶处理,制备多孔玉米淀粉,然后以环氧氯丙烷(ECH)为交联剂,合成具有多孔结构的颗粒态交联淀粉絮凝剂,并对交联工艺进行了初步优化。制备多孔交联淀粉的最佳条件为:25 g多孔淀粉,碱性硫酸钠溶液用量50 mL,环氧氯丙烷用量0.75mL,反应温度25℃,反应时间18 h。     

氧化法玉米淀粉胶的制备和改性及其在内墙涂料中的应用

面临石油危机和环境恶化的双重威胁,作为石油替代品,天然高分子的开发利用又一次成为高分子材料研究领域的热点之一。本文以双氧水为氧化剂,硫酸亚铁为催化剂,将玉米淀粉氧化变性后,和苯乙烯及丙烯酸酯单体接枝共聚,获得改性玉米淀粉胶,并以其作为基料,复配得到改性玉米淀粉胶内墙涂料,明显改善了涂料的贮存稳定性和涂膜的附着力、流平性、耐水性、抗飞溅性等性能,是一种环境友好、成本低廉的内墙涂料。     

国外可降解淀粉发泡材料最新研究进展

主要综述了国外可降解环保型淀粉发泡材料的研究现状,阐述了淀粉挤出发泡和烘焙发泡以及淀粉基聚氨酯泡沫塑料的最新研究进展.同时也概述了超临界熔体挤出法应用于淀粉发泡的最新研究成果和淀粉发泡过程的模型建立,为淀粉发泡材料的进一步工业化应用提供了一定的参考.     

天然高分子吸水材料的制备工艺与性能评价

以天然薯粉为基本原料,采用直接聚合法和反相悬乳法两种不同方式,研究了淀粉接枝丙烯酸制备高叹水材料的工艺条件及产品性能,探讨了接枝剂用量、丙烯酸中和度、反应温度、反应时间等对产品吸水性能的影响,评价了下同方法制备所得吸水材料对淡、盐、肥水的吸水速率、吸水量、保水率和重复使用性能．研究结果表明,直接聚合法在简化工艺、降低成本等方面有明显优势,可制得吸水量约410g／g,吸盐水量约40g/g,吧乏吧水量约49g／g,且可多次重复使用的产品,具有广泛的工农业和市场应用前景．