酶膜反应器制备的蛋清水解物的营养评价

对酶膜反应器(EMR)制备的蛋清水解物进行营养评价。用配备截留分子质量10kD 超滤膜的EMR 制备并经大孔吸附树脂层析得到精制的蛋清水解物。以天然蛋清为对照物，分析水解物的游离氨基酸组成、相对分子质量分布及其氨基酸组成，并根据氨基酸分析结果进行氨基酸评分。结果发现：水解物的游离氨基酸质量分数为0.386%；水解物中2～4 个氨基酸残基组成的肽的质量分数约占71%；EMR 蛋清水解物所含的必需氨基酸占氨基酸总量的44.8%，氨基酸评分值为113.3，比天然蛋清的氨基酸评分值提高105.6%。该水解物易被人体吸收、营养均衡而价值较高，可广泛应用于营养保健食品中。

Nutritional Evaluation of Egg White Hydrolysates Prepared Using an Enzymatic Membrane Reactor

In this study, the egg white hydrolysates which were prepared using an enzymatic membrane reactor (EMR) equipped with a 10 kD molecular weight cut-off ultra-filtration membrane, and refined by macroporous adsorption resin chromatography were analyzed and evaluated for their nutritional composition. Native egg white was used as the control to analyze their free amino acid composition, relative molecular mass distribution and amino acid composition. Besides, their amino acid scores were determined according to the analytical results of amino acid composition. The results indicated that the free amino acid content of the hydrolysates was 0.386%. The peptides composed of 2 to 4 amino acid residues in the hydrolysates were approximately 71%. The essential amino acids in the hydrolysates represented approximately 44.8% of the total amino acids and their amino acid score was 113.3, which was much higher than that of native egg white (55.1). The hydrolysates were characteristic of fast absorption, balanced nutrition and high healthcare value. As a conclusion, they can be extensively applied in functional food products.