Clark R M, Hundrieser K H, Ross S, Brown P B
J Pediatr Gastroenterol Nutr. 1984 Sep;3(4):567-70. doi: 10.1097/00005176-198409000-00016.
Milk was collected from five mothers. Upon collection, serum-stimulated and serum-independent lipolytic activities were determined. The milk samples were aliquoted and stored at 25, 4, -20, and -70 degrees C. After storage for 3, 6, 12, and 24 h, serum-stimulated and -independent activities were again determined and compared with the initial activities. Storage at 25 degrees C resulted in a significant (p less than 0.05) decrease in lipolytic activity. Serum-stimulated activity decreased 83.4% and serum-independent activity decreased 66.9% over the 24-h period. Storage at 4 degrees C resulted in a significant (p less than 0.05) decrease of 22.6% in serum-stimulated activity and a 7.2% decrease in serum-independent activity. No significant changes were observed in milk stored for 24 h at -20 and -70 degrees C. Milk was stored at -20 and -70 degrees C for an additional 1, 2, and 4 weeks. Serum-stimulated lipolysis did not change significantly over the 4-week period. Serum-independent lipolysis increased significantly (p less than 0.05) with storage time. Storage at -20 degrees C resulted in an increase of 20% and storage at -70 degrees C resulted in an increase of 36% over the 4 weeks.
从五位母亲处采集了乳汁。采集后，测定了血清刺激和非血清依赖的脂解活性。将乳汁样本进行分装，并分别储存在25℃、4℃、-20℃和-70℃。储存3小时、6小时、12小时和24小时后，再次测定血清刺激和非血清依赖的活性，并与初始活性进行比较。在25℃储存导致脂解活性显著（p<0.05）下降。在24小时内，血清刺激的活性下降了83.4%，非血清依赖的活性下降了66.9%。在4℃储存导致血清刺激的活性显著（p<0.05）下降22.6%，非血清依赖的活性下降7.2%。在-20℃和-70℃储存24小时的乳汁未观察到显著变化。乳汁在-20℃和-70℃下额外储存1周、2周和4周。在4周期间，血清刺激的脂解作用没有显著变化。非血清依赖的脂解作用随储存时间显著增加（p<0.05）。在-20℃储存4周导致增加20%，在-70℃储存4周导致增加36%。
