不同酸奶脂肪营养价值的评价及其影响因素

Nutritional value of fat in yogurt and its influencing factors

酸奶因对人体的多种健康作用成为健康饮食的标志,提高酸奶营养与健康功能成为研发新产品的重要内容。在分析烧酸奶(A组)、益生菌酸奶(B组)、普通酸奶(C组)脂肪酸分布及其营养价值差异基础上,探讨了原料脂肪、前处理工艺、发酵剂、乳酸菌数量对脂肪营养价值的影响。结果显示,三类酸奶具有相同的脂肪酸组成和无统计学差异的饱和脂肪酸(SFA)、单不饱和脂肪酸(MUFA)含量,但多不饱和脂肪酸(PUFA)表现为A组显著低于B与C组,而n-6/n-3 PUFA比例为A组(5.5)显著高于C组(2.8)和B组(2.4)组,PUFA/SFA则为B组最高(P<0.05)。因素相关性和方差分析表明,显著影响酸奶脂肪酸分布和脂肪营养价值的因素依次为原料脂肪、发酵剂、乳酸菌数量和原料前处理工艺。结果可为指导酸奶消费和生产更高营养价值的酸奶产品提供参考。

Yogurt is a healthy diet due to its beneficial bacteria to human body.Improving nutrition and function of yogurt is important for the development of new yogurt product.Based on the difference of fatty acid and nutritional value in caramel flavor yoghurt(A),probiotic yoghurt(B)and regular yoghurt(C),the effects of fat in raw material,pretreatment process,starter and lactic acid bacteria(LAB)amount on the fatty acid profile and yogurt nutrition were studied.No statistical difference in saturated fatty acid(SFA)and monounsaturated fatty acid(MUFA)among three groups of yoghurt,but a significantly low polyunsaturated fatty acid(PUFA)was tested in group A than that in groups C and B.The ratio of n-6/n-3 PUFA in group A(5.5)was significantly higher than that in group C(2.8)and B(2.4),and the PUFA/SFA in group B was the highest(P<0.05).The correlation and variance analysis indicated that the order of influencing factors on fatty acids and nutritional value of yogurt was raw fat>starter>LAB counts>pretreatment of raw material.Those results could provide a guidance for consumer and yogurt product development.