亚麻籽全籽蛋白和亚麻籽饼蛋白提取工艺优化及其品质研究

Optimization of extraction process of flaxseed whole seed protein and flaxseed cake protein and analysis of their quality

以亚麻籽全籽和亚麻籽饼为原料,采用超声-碱溶工艺提取蛋白质。以蛋白质提取率为指标,在单因素试验的基础上通过响应面法优化提取工艺,并对2种蛋白质品质进行对比分析。结果表明:亚麻籽全籽蛋白最佳提取工艺为超声时间60 min、超声功率400 W、超声温度45℃,在此条件下亚麻籽全籽蛋白的提取率为53.47%;亚麻籽饼蛋白最佳提取工艺为超声时间60 min、超声功率480 W、超声温度40℃,在此条件下亚麻籽饼蛋白的提取率为56.47%。亚麻籽全籽蛋白的纯度和表面疏水性指数(H_(0))均显著高于亚麻籽饼蛋白(P<0.05),2种亚麻籽蛋白的必需氨基酸含量均占总氨基酸含量的40%以上。亚麻籽饼蛋白较亚麻籽全籽蛋白二级构象更稳定、更有序。亚麻籽全籽蛋白具备较高的泡沫稳定性、持油性、起泡能力、乳化活性和乳化稳定性,而亚麻籽饼蛋白具有较高的溶解性和持水性。

Using flaxseed whole seed and flaxseed cake as raw materials,the protein was extracted by ul-trasonic-alkaline solution process.Taking protein extraction rate as the index,the extraction process was optimized by response surface methodology on the basis of single factor experiments,and the quality of two types of proteins was compared.The results showed that the optimal extraction conditions for flaxseed whole seed protein were ultrasound time 60 min,ultrasound power 400 W,ultrasound temperature 45℃.Under these conditions,the extraction rate of flaxseed whole seed protein was 53.47%.The optimal extraction conditions for flaxseed cake protein were ultrasound time 60 min,ultrasound power 480 W,ultrasound temperature 40 C.Under these conditions,the extraction rate of flaxseed cake protein was 56.47%.The purity and surface hydrophobicity index(H_(0))of flaxseed whole seed protein were significantly higher than those of flaxseed cake protein(P<0.05),and the essential amino acid content of two types of pro-teins were more than 40%of the total amino acids.Flaxseed cake protein had a more stable and ordered secondary conformation compared to flaxseed whole seed protein.Flaxseed whole seed protein had higher foam stability,oil retention,foaming ability,emulsifying activity and emulsifying stability,while flaxseed cake protein had higher solubility and water retention.