美拉德反应对花生分离蛋白体外消化特性的影响

为了探讨花生蛋白饮料在热杀菌过程中的美拉德反应发生情况以及对后续模拟消化特性的的影响,本文在80℃、100℃、121℃条件下分别对外加葡萄糖的花生分离蛋白湿热处理30min,然后进行体外模拟消化,并与同样处理条件但未加葡萄糖的样品进行比较.分别检测了热处理后样品在294nm和420nm处的吸光值,模拟消化产物的水解度、蛋白消化率、肽分子量分布和游离氨基酸组成.试验结果表明:未加葡萄糖的样品热处理后也发生了褐变,加入葡萄糖后褐变程度显著加深;热处理及美拉德反应致使后续的模拟消化产物中分子量较大的肽段含量增加;三个热处理条件中只有121℃超高温热处理有利于消化产物水解度的提高,而美拉德反应的发生总体上不利于花生分离蛋白的消化利用.

Effect of thermal treatment on the in vivo digestion characteristics and antioxidant activity of PPI-glucose

Thermal sterilization is widely adopted in peanut protein beverage processing, and may cause Maillard reaction (MR). This paper was designed to research the effect of thermal sterilization induced MR on the subsequent simulated gastrointestinal digestion. Peanut protein isolate (PPI) and glucose (1:1) were heat-treated in 80/100/121 oC for 30 min, then subjected to a simulated gastrointestinal digestion to evaluate the digestion characteristics. PPI without glucose, as a control group, was dealt in the same conditions. Absorbance in 294/420 nm of heat-treated samples and degree of hydrolysis (DH), protein digestibility (PD), molecular weight distribution, free amino acid composition of simulated gastrointestinal digestion products were measured. The experimental results showed that: compared to the control group, PPI heat-treated with glucose caused stronger MR. Heat treatment and MR leaded to an increase of larger molecular weight peptides content. Only heat-treated in 121 oC for 30 min had contributed to the DH increase of simulated gastrointestinal digestion products, and from a general view, MR gone against the digestive and utilizable performance of PPI.