Accelerated shelf life testing of whey-protein-coated peanuts analyzed by static headspace gas chromatography

Four different formulations of whey-protein-based coatings were used to coat peanuts. Four controls were used to investigate the effects of different ingredients in the coating formulation on the peanut shelf life. Untreated peanuts were designated as the reference. The peanut samples were stored in duplicate at 40, 50, and 60 °C for storage durations of up to 31 weeks. The analysis of hexanal indicated that the coated samples were oxidized significantly slower than the reference; hence, the predicted shelf life was longer for the coated samples. However, the investigation of the control ingredients revealed that even when only water was applied onto the peanuts the oxidation was delayed.