狭果茶藨子营养成分分析与氨基酸提取工艺优化及评价

Analysis of nutritional components and optimization of amino acidextraction process of Ribes stenocarpum Maxim

以青藏高原狭果茶藨子为原料,对其果实中营养物质含量进行了测定,通过超声波辅助提取法结合响应面试验优化氨基酸提取工艺参数,并基于国际粮农组织和世界卫生组织(World Health Organization/Food and Agriculture Organization of the United Nations,WHO/FAO)氨基酸衡量标准,评价了狭果茶藨子果实的营养品质。结果表明,狭果茶藨子果实中粗脂肪含量为2.2 g/100 g,粗蛋白含量为7.9 g/100 g,粗纤维含量为24.4 g/100 g,总糖含量为17.0 g/100 g,同时富含K、Ca、Mg等微量矿质元素。利用单因素试验、Plackett-Burman试验、响应面试验优化得到氨基酸最佳提取工艺参数为:超声时间30 min、液料比35∶1(mL∶g)、超声温度55℃、超声功率300 W、乙醇体积分数40%、提取次数2次,此条件下狭果茶藨子氨基酸提取量达(47.57±0.67)mg/g。采用氨基酸分析仪检出狭果茶藨子果实中含有17种氨基酸,必需氨基酸总量为1.81 g/100 g,占总游离氨基酸的38.51%,其构成比例基本符合WHO/FAO的标准,是一种营养丰富的野生浆果资源,具有较好的开发利用前景。

In this study,the nutrient of Ribes stenocarpum Maxim from Qinghai-Tibetan Plateau was determined,and the extraction process parameters of amino acids were optimized by ultrasonic extraction combined with response surface test.The amino acid composition was analyzed using WHO/FAO amino acid reference model as the evaluation standard.The results showed that R.stenocarpum fruit contained 2.2 g/100 g crude fat,7.9 g/100 g crude protein,24.4 g/100 g crude fiber and 17.0 g/100 g total sugar,and was rich in trace mineral elements,such as K,Ca,Mg and Fe.Single-factor experiment,Plackett-Burman experiment and response surface experiment were used to optimize the extraction process conditions,and the optimal extraction parameters of amino acids were obtained as follows:ultrasonic treatment for 30 min at 55℃with solid-liquid ratio of 1∶35(g∶mL);ultrasonic power was 300 W,ethanol concentration was 40%,and extracted for 2 times.Under this condition,the extraction amount of free amino acids from R.stenocarpum fruit was(47.57±0.67)mg/g.The results of amino acid analyzer showed that there were 17 kinds of amino acids in R.stenocarpum fruit.The total amount of essential amino acids was 1.81 g/100g,which accounting for 38.51%of the total free amino acids.The proportion of essential amino acids in R.stenocarpum fruit was basically in line with the standard of WHO/FAO.R.stenocarpum fruit was a kind of wild berry resource with rich nutrition and had good development and utilization prospects.