Packaging preservation of β-carotene in sweet potato flakes using flexible film and an oxygen absorber

Sweet potato flakes are potentially an affordable, shelf-stable source of provitamin A beta-carotene. Because beta-carotene is susceptible to oxidative degradation, particularly in dehydrated food materials exposed to atmospheric oxygen, several packaging conditions were evaluated for enhancement of beta-carotene retention in sweet potato flakes during storage. The flakes were packaged in either a polypropylene film thigh oxygen permeability) with air headspace or a nylon laminate film (low oxygen permeability) with air headspace, under vacuum, or with an Ageless oxygen absorber sachet enclosed. Packaged flakes were stored in the dark at ambient laboratory temperature (similar to 23C), and beta-carotene content was determined at intervals from 0 to 210 day storage using reversed-phase liquid chromatography. Among the packaging conditions tested beta-carotene retention was enhanced incrementally as the apparent availability of oxygen was reduced (nylon > polypropylene, oxygen absorber > vacuum > air headspace). The combined use of oxygen absorbers and flexible oxygen barrier film gave excellent retention of beta-carotene during the 210 day trial.