卫生研究

目的 分析测定银川市售乳及乳制品中脂肪酸含量，评价其营养价值。方法 于2022—2023年采集银川市售22种乳及乳制品，宁夏生产14种，非宁夏生产的8种，依据《食品安全国家标准食品中脂肪酸的测定》(GB 5009.168—2016)第一法进行脂肪酸测定，利用脂肪酸多不饱和指数、致动脉粥样硬化指数和血栓形成指数评价乳及乳制品营养价值。结果 宁夏产乳及乳制品脂肪酸共有25种，种类多于非宁夏产乳制品。主要的饱和脂肪酸(saturated fatty acids, SFA)是棕榈酸(30.14%～42.57%),主要的单不饱和脂肪酸(monounsaturated fatty acids, MUFA)是油酸(15.45%～25.21%),主要的多不饱和脂肪酸(polyunsaturated fatty acids, PUFA)是亚油酸(1.79%～9.37%),α-亚麻酸含量为0.04%～0.95%,n-3 PUFA含量为0.14%～0.95%。油酸含量较高的有纯牛乳、枸杞乳、中老年乳粉和羊乳粉，亚油酸含量较高的有核桃牛乳和中老年乳粉。宁夏产纯牛乳中油酸和亚油酸高于进口纯牛乳，n-6 PUFA/n-3 PUFA值远低于进口纯牛乳。宁夏产枸杞乳中油酸、亚油酸含量与宁夏产纯牛乳接近，高于儿童乳，总脂肪含量低于儿童乳。浓缩牛乳、核桃牛乳、甜牛乳、纯牛乳、枸杞乳、中老年乳粉1、羊乳粉等n-6 PUFA/n-3 PUFA比值接近中国营养学会推荐人体膳食脂肪酸理想摄入值。除低脂纯牛乳、冰激凌酸乳、进口纯牛乳、儿童牛乳1、中老年乳粉1和羊乳粉外，其余宁夏乳及乳制品n-6 PUFA/n-3 PUFA的比值均接近联合国粮食与农业组织及世界卫生组织推荐值。SFA∶MUFA∶PUFA为(1.99～4.23)∶1∶(0.08～0.38),脂肪酸多不饱和指数范围为1.87～11.27,致动脉粥样硬化指数范围为1.67～4.32,血栓形成指数范围为2.34～5.76。结论 银川市售22种乳及乳制品脂肪酸构成不同，营养价值也有所不同。

OBJECTIVE To analyze fatty acid composition of milk and dairy products sold in Yinchuan City, and to evaluate their nutritional value.METHODS Twenty-two types of milk and dairy products were collected in 2022-2023, including 14 types produced in Ningxia and 8 types not produced in Ningxia. Fatty acids were determined and analyzed according to the first method of National Standard for Food Safety Determination of fatty acids in Food(GB 5009.168—2016). The fatty acid polyunsaturated index(PI), atherogenic index(AI) and thrombosis index(TI) were used to evaluate the nutritional value of milk and dairy products.RESULTS There were 25 kinds of fatty acids in milk and dairy products produced in Ningxia, which were more than those not produced in Ningxia. The main saturated fatty acids(SFA)were palmitic acid(30.14%-42.57%), the main monounsaturated fatty acids(MUFA)were oleic acid(15.45%-25.21%), the main polyunsaturated fatty acids(PUFA)were linoleic acid(1.79%-9.37%), the content of α-linolenic acid was 0.04%-0.95%, n-3 PUFA was 0.14%-0.95%. Oleic acid of adult milk powder, sheep milk powder, pure milk and Ningxia wolfberry milk were higher than others, linoleic acid of adult milk powder and walnut milk were higher than others. The value of oleic acid and linoleic acid of Ningxia pure milk was higher than that in imported pure milk, and the value of n-6 PUFA/n-3 PUFA was much lower than that in imported pure milk. The content of oleic acid and linoleic acid in Ningxia wolfberry milk was close to that of pure milk, higher than that of children's milk, and the total fat content was lower than that of children's milk. The n-6 PUFA/n-3 PUFA ratio of concentrated milk, walnut milk, sweet milk, pure milk, Ningxia wolfberry milk, adult milk powder 1, sheep milk powder was close to the ideal intake value of dietary fatty acids recommended by the Chinese Nutrition Society. Except for low-fat pure milk, ice cream yogurt, imported pure milk, children's milk 1,adult milk powder 1 and sheep milk powder, the n-6 PUFA/n-3 PUFA ratio of other milk and dairy products in Ningxia were close to the recommended value of the Food and Agriculture Organization of the United Nations and World Health Organization. SFA∶MUFA∶PUFA was(1.99-4.23) ∶1∶(0.08-0.38), PI range: 1.87-11.27, AI range: 1.67-4.32, TI range: 2.34-5.76.CONCLUSION The fatty acid composition of 22 types of milk and dairy products in Yinchuan City was different, and the nutrition was slightly different.