Abstract: To compare the differences in nutritional composition and functional properties between frozen concentrated milk and whole milk powder, this study measured changes in immunoglobulins (Igs), lactoferrin, B vitamins, and metabolomics. It was found that the frozen concentrated milk had significantly higher levels of IgA and IgG, lactoferrin, B vitamins, vitamin A, vitamin D, and vitamin C compared to whole milk powder. Non-targeted metabolomics analysis revealed that the main differential metabolites between frozen concentrated milk and whole milk powder were annotated to multiple key pathways involved in amino acid and peptide (isoleucine, levodopa, phenylalanine-tyrosine, creatine, D-proline, L-glutamate, L-arginine, asymmetric dimethylarginine, L-pipecolic acid, L-histidine, and N-methyl-L-glutamate) metabolism, and carbohydrate (maltotetraose, trehalose, D-maltose, and isomaltose) metabolism. These metabolites showed significantly higher relative expression levels in frozen concentrated milk compared to whole milk powder (P < 0.05). The results indicate that frozen concentrated milk is significantly superior to whole milk powder in terms of nutritional composition.

Key words: frozen concentrated milk, whole milk powder, nutrients, non-targeted metabolomics

摘要： 为比较冷冻浓缩乳与全脂乳粉营养成分的差异，对免疫球蛋白（immunoglobulin，Ig）、乳铁蛋白、维生素及代谢组学变化进行测定。结果表明：冷冻浓缩乳组IgA、IgG、乳铁蛋白、B族维生素、VA、VD和VC含量显著高于全脂乳粉组；分析非靶向代谢组学数据发现，冷冻浓缩乳组与全脂乳粉组的主要差异物被注释到氨基酸代谢合成、肽类代谢合成和碳水化合物代谢合成的多条关键通路中，主要是异亮氨酸、左旋水苏碱、脯氨酰-酪氨酸、肌酸、D-脯氨酸、L-谷氨酸、L-精氨酸、不对称二甲基精氨酸、L-哌可酸、L-组氨酸、N-甲基-L-谷氨酸等氨基酸和小肽类物质和麦芽四糖、海藻糖、D-麦芽糖、异麦芽糖等碳水化合物类代谢物，它们的相对表达量在冷冻浓缩乳组显著高于全脂乳粉组（P＜0.05）。本研究结果表明，冷冻浓缩乳在营养成分上显著优于全脂乳粉。

关键词: 冷冻浓缩乳, 全脂乳粉, 营养物质, 非靶向代谢组学