商品奶中褪黑激素的含量分析

Analysis of Melatonin Concentration in Milk Products

为研究商品奶中褪黑激素的浓度,比较不同品牌、不同品种、不同产地商品奶中褪黑激素浓度的差异,于2015年2月选择北京一中型超市,共采集6个品牌、7个品种,以及3个产地的奶制品,通过放射免疫法检测奶制品中褪黑激素的浓度。结果表明,除无菌砖脱脂鲜牛奶外,同一品种不同品牌,以及同一品牌不同品种商品奶中褪黑激素的浓度无显著差异(P>0.05)。品牌1无菌砖脱脂鲜牛奶中褪黑激素浓度显著高于无菌砖纯牛奶、无菌枕纯牛奶、无菌砖鲜牛奶、巴氏奶、儿童奶和酸奶(P<0.05),品牌5的无菌砖纯牛奶褪黑激素浓度在3个产地之间无差异(P>0.05)。由此可见,北京市售脱脂鲜牛奶中褪黑激素浓度最高,而品牌和产地对其他品种商品奶中的褪黑激素浓度无影响。此外,目前市售牛奶中褪黑激素的浓度基本在15 pg/m L以下,较专门生产的夜间牛奶的褪黑激素浓度低很多,开发高褪黑素夜间奶具有一定的可行性。

This study was aimed to investigate the melatonin concentration of milk products and the difference of various brands, different kinds and different producing areas on melatonin concentration of milk products. A variety of milk products （six brands, seven kinds and three producing areas） were collected from a supermarket of Beijing in February 2015. Melatonin concentrations were measured by a commercial radioimmunoassay kit. The results show that no significant difference in melatonin concentrations were observed in the same kind from different brands and the different kinds of the same brand except for the skim milk （P〉0.05）. The melatonin concentration of skim milk from brand 1 is higher than that of aseptic brick pure milk, aseptic pillow milk, pasteurized milk, fresh milk, kids＇ milk and yoghourt （P〈0.05）. The aseptic brick pure milk products of brand 5 which were manufactured in three different producing areas are no differences in melatonin concentrations （P〉0.05）. Therefore, the melatonin concentration of skim milk is the highest in Beijing and the brands have no effects on melatonin concentration as well as the producing areas. In addition, the melatonin concentration of milk products is almost below 15 pg/mL and is significantly lower than the specializing nightmilk, hence the development of nightmilk with a high proportion of melatonin in China is feasibility.