Gamma irradiation of trilamellate packaged yellow corn (Zea mays) kernels enhances lutein content and shelf life

Yellow corn kernels were subjected to gamma (γ) irradiation (1.0–10.0 kGy), post packaging in polypropylene/polyethylene terephthalate/aluminium foil trilamellate. These packaged‐irradiated corn grits were stored under ambient conditions (23 ± 2°C, 80% R.H.) and their shelf lives were ascertained chiefly w.r.t. lutein and aflatoxin contents. Among all samples investigated, 3 kGy‐irradiated samples exhibited a unique combination of maximum carotenogenesis (lutein content: 422 ± 2.30 µg/100 g [d.b.] corn grits, on day 120) and minimum aflatoxin content (1.35 ± 0.10 µg/kg [d.b.] corn kernels, on day 120) during storage, causing minimum alterations to their sensory, physicochemical, phytochemical, and nutritional characteristics. Thus, packaged‐cum‐3 kGy‐irradiated yellow corn kernels with a lead of 30 days in shelf life vis‐à‐vis their non‐irradiated counterparts were considered to be the “best shelf stable” (shelf life: 120 days) sample set and γ‐irradiation in combination with flexible packaging was established to be a new preservation technology for this horticultural produce. PRACTICAL APPLICATIONS: Gamma (γ) irradiation is a well‐known food preservation technology. Although there is published literature on the effects of the application of this technology on yellow corn kernels; enhancement of the content of its biotherapeutic molecule, lutein has not been reported. This study reports for the first time on increased carotenogenesis, that is, enhanced production of lutein (a member of the family of carotenoid pigments) in corn kernels consequent to γ‐irradiation, besides increasing shelf lives of the irradiated kernels. The data presented in this study would be certainly useful for producers and consumers alike and offers a new advantage of γ‐irradiation to industrial/commercial food irradiators who can commercialize the utilization of irradiated corn kernels as enhanced sources of its major bioactive compound, lutein.