Food irradiation and its role in shelf life extension of horticulture produce: a comprehensive evaluation of studies carried out in India and abroad

Food irradiation is the process of treating foods to a controlled source of ionizing radiation, to reduce post-harvest losses and ensure its safety. With respect to horticulture produce, the role of food irradiation has been well established to fulfill the phytosanitary requirement of the importing countries and also to ensure food safety in certain commodities. Still for establishing its relevance in extending the shelf-life of horticulture produce, substantial scientific inputs are required. Our objective was therefore to summarize in brief the research findings where role of radiation processing in shelf-life extension of horticulture produce has been addressed. Low dose (0.1 kGy) of γ-radiation resulted in sprout inhibition in potatoes and onions, thus prolonging their storage life upto 4 months at 11-12℃. Radiation processing also delayed ripening process in the climacteric fruits by a week upto one month depending on the cultivars and stored condition. Shelf-life of button mushroom (Agaricus bisporus) was extended up to 10-15 days by γ-radiation treatment of 2-3 kGy and storage at 10±2℃ . A 5 kGy radiation dose and 10℃ storage temperature increased the shelf life of peeled ginger samples upto 70 days. Irradiation of guava fruits with 0.1 kGy γ-radiation increased its post harvest life by 8 days. Shelf-life of Litchi was increased upto 28 days by radiation treatment at 0.5 kGy and subsequent low temperature storage. Shelf-life of leafy vegetables increased upto 20 days by a combination process including γ-radiation (Khade, et.al., unpublished data). Electron beam irradiation (2 kGy) extended shelf-life of fresh strawberry fruits upto 4 day. Apples irradiated at 0.2-0.4 kGy showed improved quality upto 3 months of storage. Shelled sweet corn kernels treated with combination process including γ-radiation (5 kGy) treatment showed prolonged shelf-life of 30 days at 4℃ (Kumar S. et.al., unpublished data). In recent study conducted by us on shelf life extension of fresh date palm fruit using γ-radiation treatment and other hurdles have shown promising results. Thus, it can be concluded that besides ensuring food safety and security, radiation processing has tremendous potential of extending the shelf-life of horticulture produce in its fresh or minimally processed form. (author)