Hygienic-sanitary quality and effect of freezing time and temperature on total antioxidant capacity of human milk

Abstract

Knowledge of the hygienic-sanitary quality of raw human milk helps to establish the best storage conditions for the preservation of its nutritional and functional components. Therefore, this study aimed to evaluate the hygienic-sanitary quality of human milk extracted at the mothers’ homes, and to analyze the effect of freezing time and temperature on the milk’s total antioxidant capacity. Milk of five mothers was evaluated individually for Staphylococcus aureus, total aerobic mesophilic counts, mold and yeasts, total and thermotolerant coliforms. The milk pool was stored at -8 °C, -18 °C and -40 °C for 2, 4, 8 and 15 days and analyzed for the total antioxidant capacity by the 2,2-diphenyl-1-picrylhydrazyl free radical and 2,2-azino 3-ethylbenzothiazoline-6-sulfonic acid scavenging methods. The microbiological analyses of the raw human milk samples indicated counts of all the studied microorganisms above the safe limits. Related to the effect of freezing time and temperature on total antioxidant capacity, it was concluded that, regardless of the freezing temperature, a significant reduction occurred on total antioxidant capacity over time and that the lower the storage temperature, the greater its total antioxidant activity.

The Influence of Time and Temperature on Human Milk Storage Antioxidant Properties, Oxidative Stress, and Total Protein

“…There was variation in the antioxidant profile until the 21 st day at both temperatures (4 °C and -20 °C). However, Lopes et al (2020) observed a change in the antioxidant profile when the human milk was stored at temperatures lower than -40 ºC, demonstrating that freezing may not be the best way to store human milk.…”