Stability of omega-3 enriched milk powder in different commercial packages stored under accelerated conditions of temperature and relative humidity

The effect of two storage conditions (34 °C/83% relative humidity (RH) and 43 °C/no RH control) on the stability of whole milk powder (WMP) with added omega-3 microcapsules packed in 4 different packages was evaluated. The packages were: flexible metallised polyethylene terephthalate laminated to low density polyethylene (PETmet/LDPE); flexible bioriented polypropylene laminated to polypropylene (BOPP/PP); three-piece metal can and three-piece composite can, whose body was composed of combined materials (lamination of plastic, cellulose and aluminium foil). The results showed that oxygen consumption in the package headspace was directly related to storage conditions. A lactose crystal formation occurred in the product in BOPP/PP stored at 34 °C/83% RH and in products in metal and composite cans stored at 43 °C. After 15 weeks of storage, microencapsulation was effective in maintaining the Brazilian label claim of "source of omega-3″, regardless of the type of packaging and storage condition.