捐赠母乳宏量营养素和能量的影响因素

Influence factors of macronutrients and energy content of donor human milk

目的:探讨巴氏消毒、储存时间及解冻方式对捐赠母乳宏量营养素和能量的影响,为母乳库捐赠母乳的合理应用提供理论依据。方法:收集33例捐赠母乳样本,在巴氏消毒前后分析营养成分;将消毒后的每份样本平均分为9份,于-20℃冷冻储存30、60、90 d时各取3份,分别用室温条件、4℃冷藏条件、37℃水浴快速解冻3种方式将母乳解冻后,测定营养成分并进行比较分析。结果 :巴氏消毒后母乳中脂肪含量及能量均有所降低(P<0.05),随储存时间延长,捐赠母乳脂肪、蛋白质和能量显著下降(P<0.01),整个过程(巴氏消毒+冷冻90 d)分别下降36.6%、32.6%和22.6%。不同解冻方式对母乳蛋白质的影响较大,冷藏解冻时母乳蛋白质的含量最高(P<0.01)。结论:捐赠母乳在经过巴氏消毒、冷冻保存后,营养成分明显衰减,在将捐赠乳喂养早产儿前应考虑到这种变化,宜尽早使用;冷冻的捐赠乳使用前最好选择4℃冷藏解冻的方式。

Objectives To explore the effect of holder pasteurization, frozen storage time and thawing methods on macronutrients and energy content of donor human milk, and to provide theoretical basis for the rational use of breast milk. Methods Thirty-three samples of donor human milk were collected and an aliquot of each sample was analyzed before and after pasteurization. The remaining milk after pasteurization was split into 9 aliquot,and frozen at-20 ℃. After 30, 60, and 90 days, the milk was thawed by three different methods of room temperature, 4 ℃ refrigeration, and 37 ℃ water bath, respectively. The nutrient components of each aliquot were analyzed and compared. Results We observed a mild reduction in fat and energy content after pasteurization（P〈0.05）. A significant decrease of fat, protein and energy content with the prolonged storage time was observed（P〈0.01）, and during the whole process（pasteurization ＋ frozen storage）, the decrease of fat, protein and energy content was 36.6%, 32.6% and 22.6%, respectively. The protein was influenced mostly by different thawing methods and the content of protein reached highest while thawed at 4 ℃ refrigeration. Conclusions Holder pasteurization and frozen storage at-20 ℃ significantly reduce fat, protein and energy content of donor human milk. The donor milk should be used as quickly as possible when applied for preterm infants and thawing at 4 ℃ refrigeration is recommended before delivery to newborn infants.