水酶法从菜籽中提取油及水解蛋白的研究

Aqueous enzymatic extraction technology of oil and protein hydrolysates from rapeseed

为了同时从菜籽中提取清油和水解蛋白,依次使用复合细胞壁多糖酶和碱性蛋白酶（Alcalase 2.4 L）水解湿磨菜籽浆,并利用大孔吸附树脂纯化水解蛋白液.结果表明：经过酶解（复合细胞壁多糖酶：浓度3%（v/w）,pH 5.0,48℃,5 h;Alcalase 2.4 L：浓度1.5%（v/w）,初始pH 9.0,60℃,3 h）、洗渣和破乳后总菜籽清油提取率为88%～90%,总水解蛋白提取率为93%～95%.和溶剂萃取油相比,水酶法提取油的酸价偏高,颜色略深,但过氧化值低,两者皂化价,碘价和脂肪酸组成均接近.菜籽水解蛋白分子量小于1500的组分约占96%,其中小于600的约占87%.经过大孔吸附树脂纯化后,菜籽肽中糖和灰分含量显著降低,硫苷和植酸均未检出.

To obtain rapeseed free oil and protein hydrolysates simultaneously, wet-milled rapeseed slurry was treated with complex cell-wall polysaccharides degrading enzymes and Alcalase 2.4 L sequentially. Results show that the total extraction rates of free oil and protein hydrolysates are 88%~90% and 93%~95%, respectively, after combination of optimized enzyme hydrolysis （complex cell-wall polysaccharides degrading enzymes： enzyme concentration 3%（v/w）, pH 5.0, 48℃, 5 h; Alcalase 2.4 L： enzyme concentration 1.5%（v/w）, initial pH 9. 0, 60℃, 3 h）, washing and demulsification steps. Compared with solvent-extracted oil, the content of free fatty acid of enzyme-extracted oil is higher while the peroxide value is lower. The color of enzyme-extracted oil is slightly darker than that of solvent-extracted oil. The iodine value, saponification value and fatty acid composition between them are similar. Protein hydrolysates are composed of about 96% of peptides less than 1500 Da, of which about 87% are less than 600 Da. Protein hydrolysates are purified by macroporous adsorption resin. The sugar and ash contents of protein hydrolysates are significantly reduced and no glucosinolates and phytic acid are detected after purification.