Assessment of oxygen sequestration on effectiveness of Purdue Improved Crop Storage (PICS) bags in reducing carotenoid degradation during post-harvest storage of two biofortified orange maize genotypes

Abstract

Increasing adoption of biofortified orange maize in developing countries requires economical storage methods to manage product quality and carotenoid retention. This study assessed the utility of the Purdue Improved Crop Storage (PICS) bags with a specific focus on retention of provitamin A and other carotenoids in two biofortified maize genotypes (OPVI and OPVII). Grain was stored at ambient conditions for eight months in PICS bags with and without an O2 scavenger, (PICS-oxy) and (PICS-noxy), respectively, or in common polypropylene woven bags. After 4 months of storage carotenoid content was significantly higher (p < 0.05) in grain stored in PICS-oxy compared to PICS-noxy or woven bags demonstrating the importance of entrapped oxygen on maize carotenoid degradation. Differences were observed in stability between the two mize genotypes. After 8 months, carotenoid stability remained dependent on storage bag and genotype with retention being greater in PICS-oxy and PICS-noxy compared to woven bags and OPVI maintained a higher carotenoid retention than OPVII maize. Oxygen content and genotype were determining factors in the effectiveness of PICS to mitigate carotenoid degradation during post-harvest storage.