Effect of packaging materials and storage conditions on physico-chemical, phytochemical and microstructural properties of bee pollen enriched milk powder

Abstract

Bee pollen being superfood was incorporated in skim milk and spray-dried to obtain bee pollen enriched milk powder (BPEMP), which was stored in ALP, BOPP/LDPE, and PET/Al foil/LDPE pouches (commonly used to pack food powders) at 5, 25 and 40°C for 1 year. The current study aims the determination and comparison of the physico-chemical, phytochemical, and microstructural properties of BPEMP with control during storage. Water activity and peroxide value increased whereas there was a significant (p<0.05) decrease in the carbohydrate content, whiteness, TPC, and DPPH radical scavenging activity of control as well as BPEMP sample during storage. SEM results initially showed the mild interaction between round particles (3 months) which further increased to emergence of mild edges (6 months), agglomeration (9 months) and irregular particles containing sharp edges (12 months) possibly because of liquid bridges’ synthesis and lactose crystallization. However, the degree of changes was low in BPEMP samples at 5°C. The powder developed crystallinity just after 3 months at 25 and 40°C which were confirmed by sharp peaks on the XRD hump of both control and BPEMP. The findings of present work recommend the storage of BPEMP in ALP at 5 and 25°C to further explore its food applications.

Keywords

• Bee pollen enriched milk powder
• Storage
• Packaging materials
• Peroxide value
• Phytochemical properties
• SEM