燕麦粉蛋白的理化性质研究

Study on Physico-chemical Properties of Oat Flour Protein

采用扫描电子显微镜(SEM)观察燕麦粉蛋白的结构特点,垂直电泳仪测定其分子量的分布范围,AR1000型动态流变仪分析其凝胶特性,结果表明:燕麦蛋白是包裹着燕麦淀粉的胶状物质,结构紧密;燕麦粉蛋白分子量分布在14.4～66.2kD之间,分子量大小在35.0～45.0kD之间和20.0～28.5kD之间蛋白含量较大;在pH5时,起泡性最差,泡沫稳定性最好,乳化性最差,乳化稳定性最好;燕麦蛋白在第一步升温过程中,贮能模量G'随着温度的增加先降低后增加,在62.1℃时的G'最小为48.11Pa,在90.8℃时G'最大为369Pa;损耗模量G"和G'的变化趋势基本相同,在62.1℃时的G"最小为38.66Pa,在93.7℃时G"最大为106.9Pa;在20～28℃之间tan(delta)>1,黏性大于弹性,28～100℃之间tan(delta)<1,黏性小于弹性。在冷却降温过程中,G'随着温度的降低在100～48℃之间缓慢增加,48～20℃之间急剧增加,燕麦蛋白的耐热性为844.1Pa,凝胶强度为9194Pa。

The physico-chemical properties of the oat protein were researched by the machine of SEM and AR1000 dynamic rheometer analyzes and so on. The results showed that, the protein is material as glue wrapping the oat starch, with maximum molecular weight 66.2 kD, and the smallest molecular weight betweenl4.4-20.0 kD; At pH 5, its foamability is the worst and the foam stability is the best. Meanwhile, the emulsibility is worst and the emulsion stability is the best; During the first temperature ascending step, G＇ reduces firsty increases with the temperature raising,with the smallest 48.11 Pa at 62.1 ℃ and the highest 369 Pa at 90.8℃; G has the same change tendency with G＇with the tan（delta） 〉 1 between 20 ~28 ℃; The stickiness is bigger than the elasticity with tan（delta） 〈 1 between 28-100 ℃, and the stickiness is smaller than the elasticity.