| Popis: |
为提高大鲵下脚料的综合利用价值，以人工养殖大鲵肝脏为原料，采用酶解法提取大鲵肝油。先对蛋白酶进行了筛选，再采用单因素实验考察了pH、液固比、酶添加量、酶解时间、酶解温度对大鲵肝油提取率的影响，在此基础上利用响应面法优化大鲵肝油提取的工艺条件，并对精炼前后大鲵肝油的理化指标及脂肪酸组成进行了测定。结果表明：大鲵肝油提取的最优工艺条件为选用木瓜蛋白酶、pH 6.5、液固比2.5∶ 1、酶添加量2 100 U/g、酶解时间4 h、酶解温度65 ℃，在此条件下大鲵肝油提取率为79.92%；粗制大鲵肝油的酸值（KOH）为5.73 mg/g，过氧化值为1.04 mmol/kg，碘值(I)为124.60 g/100 g，不饱和脂肪酸含量为69.75%；精制大鲵肝油的酸值（KOH）为0.93 mg/g，过氧化值为0.43 mmol/kg，碘值(I)为129.40 g/100 g，共检出18种脂肪酸，不饱和脂肪酸含量为73.55%，其中多不饱和脂肪酸含量为33.88%。使用木瓜蛋白酶酶解提取大鲵肝油反应条件温和、操作简便、提取率高，所得大鲵肝油品质好，不饱和脂肪酸含量丰富，具有较高的营养价值。 In order to improve the comprehensive utilization value of the waste material of giant salamander, the oil was extracted from liver of artificial cultured giant salamander by enzymatic hydrolysis method. The protease was screened, and the influences of pH, liquid-solid ratio, enzyme dosage, enzymolysis time and enzymolysis temperature on the extraction rate of giant salamander liver oil were investigated by single factor experiment. On this basis, the giant salamander liver oil extraction process conditions were optimized by response surface methodology. The physicochemical indicators and fatty acid composition of the giant salamander liver oil before and after refining were determined. The results showed that the optimal conditions of extracting oil from giant salamander liver were obtained as follows:using papain, pH 6.5, liquid-solid ratio 2.5∶ 1, enzyme dosage 2 100 U/g, enzymolysis time 4 h, and enzymolysis temperature 65 ℃. Under these conditions, the extraction rate of giant salamander liver oil was 79.92%. The acid value, peroxide value, iodine value and content of unsaturated fatty acid of the crude giant salamander liver oil were 5.73 mgKOH/g, 1.04 mmol/kg,124.60 gI/100 g and 69.75%, respectively. The acid value, peroxide value and iodine value of the refined giant salamander liver oil were 0.93 mgKOH/g, 0.43 mmol/kg, 129.40 gI/100 g, respectively. A total of 18 fatty acids were detected in refined giant salamander liver oil, and the contents of unsaturated fatty acid and polyunsaturated fatty acid were 73.55%and 33.88%, respectively. Using papain to extract giant salamander liver oil has advantages of mild reaction conditions, simple operation and high extraction rate. The giant salamander liver oil obtained is of good quality, rich in content of unsaturated fatty acids, and has high nutritional value. |
