薏仁米糠多肽的功能特性研究

摘要

The functional properties of adlay bran polypeptide obtained by two-step enzymatic hydrolysis were analyzed, and six functional properties indexes (solubility, emulsibility, emulsion stability, foaming property, foam stability and water holding capacity (WHC)) were determined under different pH and temperature conditions, at the same time, its oil absorbency was measured. The results showed that the solubility of the polypeptide was the minimum of 26.50％ at pH 4.0; and it reached the maximum of 42.13％ at the temperature of 35 ℃. The emulsibility reached the minimum of 50.52％ at pH 5.0, and it reached the maximum of 89.72％ at the temperature of 40 ℃. The WHC reached the minimum at pH 4.0, which was 6.30％,and reached the minimum of 6.81％ at the temperature of 80 ℃. The emulsion stability and foaming property were enhanced with the increase of pH value in the range of pH 5-8, and then reaching the maximum of 87.15％ and 287％ at pH 8.0, respectively. The emulsification stability reached the maximum at 60 ℃, which was 88.75％, and the foaming property was the maximum of 410.21％ at the temperature of 35 ℃, while the foam stability reached the minimum of 88.07％ at pH 6.0, reaching a maximum of 80.58％ at the temperature of 25 ℃. The oil absorption of adlay bran polypeptide was 2.17％.%该实验研究了双酶分步酶解得到的薏仁米糠多肽在不同的pH(2～8)及温度(20～50 ℃)条件下的6种功能特性指标(溶解性、乳化性、乳化稳定性、起泡性、泡沫稳定性、持水性(WHC)),同时对其吸油性进行测定.结果表明,多肽溶解性在pH4.0时达到最低值,为26.50％;在35 ℃时达到最大值,为42.13％;乳化性在pH 5.0时达到最低值,为50.52％,在40 ℃时达到最大值,为89.72％;持水性在pH4.0时达到最低值,为6.30％,在80 ℃时达到最低值,为6.81％;而乳化稳定性和起泡性在pH5.0～8.0范围内随pH值的升高而增强,均在pH8.0时达到最大值,为87.15％、287％;乳化性稳定性在60 ℃时达到最大值,为88.75％,起泡性在35 ℃时达到最大值,为410.21％;而泡沫稳定性在pH6.0时达到最低值,为88.07％,在25 ℃时达到最大值,为80.58％;薏仁米糠多肽的吸油性为2.17％.