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Storage beyond three hours at ambient temperature alters the biochemical and nutritional qualities of breast milk

M U Eteng1, P E Ebong, E U Eyong

  • 1Department of Biochemistry, College of Medical Sciences, University of Calabar, Calabar, Nigeria.

African Journal of Reproductive Health
|December 11, 2002
PubMed

The effect of storage on stability of human breast milk was investigated in 30 lactating mothers. Samples stored for 3, 6 and 24 hours at ambient temperature of 302K (29 degrees) were analysed for protein, lactose, pH, and microbial content. There were significant (p < 0.01) decreases in protein, lactose and pH upon storage for 6 and 24 hours, compared with storage for 3 hours as control. The mean +/- SEM values for protein for 6 and 24 hours were 15.56 +/- 0.48 and 13.27 +/- 0.50, compared with 17.26 +/- 0.41 for 3 hours. For lactose, corresponding values for 6 and 24 hours were 0.08 +/- 0.005 and 0.07 +/- 0.006, compared with 3 hours (0.09 +/- 0.005). The pH values were 6.1 +/- 0.09, 5.9 +/- 0.07 in 3, 6 and 24 hour samples rspectively. The skin floras investigated were Streptococcus viridians, Straphylococcus aureus and Staphylococcus albus. The microbial content increased with increase in storage time from 3 to 24 hours. The predominant bacterial specie was S. Albus, followed by S.viridians and S. aureus. A positive correlation (r = 0.453, p < 0.01) between lactose level and pH were obtained. These results suggest that breast milk is stable for 3 hours, beyond which significant changes occur in its biochemical composition and nutritional quality. The implications of these findings are discussed with respect to its consequences on their child's survival.

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