Effect of storage on retinol content and total antioxidant capacity of human milk

Purpose The purpose of this paper is to evaluate the effect of different times and freezing temperatures on the antioxidant activity of raw human milk (HM) and the impact of light by different packaging on retinol level and the antioxidant activity of pasteurized HM. Design/methodology/approach Donor milks were homogenized to form the pool of the experimental study characterized by the evaluation of the effects of time (0, 2, 4, 8 and 15 days) freezing temperatures (−3°C, −8°C and −18°C) and the interference of the type of packaging on the antioxidant activity and retinol levels of HM. Findings The existing studies do not reveal the real impact of HM storage conditions adopted by human milk banks (HMB) in Brazil on their compounds, mainly in relation to the effects of temperature and freezing time and the incidence of light on retinol levels and antioxidant activity. In view of the already documented importance of these compounds for the growth, development and health of children, it is extremely important to assess their stability according to the procedures adopted by the banks. It has been observed in this study that lower freezing temperatures (−18°C) further preserve the antioxidant activity. It was found that the amber and transparent vials wrapped with aluminum foil allowed for greater retinol stability of HM, with values of 2.501±0.757 µmol/L and 4.991±0.825 µmol/L, respectively. On the contrary, there was no significant influence on antioxidant activity. Originality/value It is suggested that HMB store milk at lower temperatures and use glass jars that block the passage of light.