母乳成分在-80℃保存过程中的稳定性研究

Study on the Stability of Human Milk Components during -80 ℃ Storage

通过对母乳脂肪酸、维生素、活性成分以及p H值和酸度在超低温冷冻条件下的稳定性研究,最终制定伊利母乳研究实物库的母乳质量标准,以确保伊利母乳研究实物库中的母乳样本在-80℃保存过程中营养成分的损失率最小。试验结果表明,母乳在-80℃冷冻保存12个月的过程中,随着保存时间的延长,维生素含量显著降低,脂肪酸、核苷酸含量以及p H值和酸度没有发生显著性变化。母乳-80℃保存3个月时,V_B_2和V_A的含量分别减少为新鲜母乳的35%和29%,V_C含量无法检出;-80℃保存12个月时,烟酸含量减少为新鲜母乳的69%。因此,从现有检测指标来看,母乳库的质量标准应根据分析研究的母乳成分而定,若分析稳定性较差的营养成分如维生素尽量使用新鲜母乳。

Based on the stability study of human milk vitamins and activity components in cryogenic freezing con-ditions,the quality standards of Yili Human Milk Physical Library were made to ensure the minimum loss of nu-trients of the human milk samples stored in Yili Human Milk Physical Library at-80 ℃. The results showed that freezing at-80 ℃ for 12 months significantly reduced vitamins contents,did not significantly change fatty acid contents nucleotide contents and p H or acidity,compared with fresh milk. V_B_2 and V_A levels were reduced to 35 %and 29 % of fresh breast milk respectively at-80 ℃ for 3 months,and VCwas not detected;nicotinic acid was reduced to 69 % of fresh breast milk at-80 ℃ for 12 months.Therefore,from the existing test indicators,the quality standards of human milk freezing storage should be based on human milk composition analysed,if stable nutritional ingredients such as fatty acids can be used to store human milk at-80 ℃ for 12 months.