A combination process including ionizing radiation for hygienization and shelf life extension of leafy vegetables

Raw leafy greens are commonly associated with global foodborne outbreaks due to pathogenic contaminants. In the current study, greens, such as spinach (Spinacia oleracea L.), coriander (Coriandrum sativum L.) and mint (Mentha spicata L.) showed presence of coliforms (including E. coli)along with other aerobic microbes, yeast and molds. These vegetables mostly consumed in raw or culinary purpose, and hence increase the chances of food borne illnesses. Moreover, the leafy greens are perishable. In this context, we optimized a combination process including radiation treatment to achieve hygienization and shelf life extension of these leafy green vegetables. The combination treatment comprising potable water wash, chlorination (NaOCl-200 ppm) followed by irradiation (2 kGy using electron beam or gamma) was developed, and the processed samples showed keeping quality up to 15 days at 4-6°C, whereas control samples spoiled within two days. The treatment resulted in coliform count below detection level while retaining the nutritional, phenolic content and organoleptic qualities. Thus, the combination treatment could ensure safety, keeping quality enhancement of perishable leafy greens and to control global food outbreaks. Electron beam over gamma processing found to be a commercial viable option due to its high throughput and equal efficacy in microbial decontaminatio

A combination process including ionizing radiation for hygienization and shelf life extension of leafy vegetables

474-486Raw leafy greens are commonly associated with global foodborne outbreaks due to pathogenic contaminants. In the current study, greens, such as spinach (Spinacia oleracea L.), coriander (Coriandrum sativum L.) and mint (Mentha spicata L.) showed presence of coliforms (including E. coli)along with other aerobic microbes, yeast and molds. These vegetables mostly consumed in raw or culinary purpose, and hence increase the chances of food borne illnesses. Moreover, the leafy greens are perishable. In this context, we optimized a combination process including radiation treatment to achieve hygienization and shelf life extension of these leafy green vegetables. The combination treatment comprising potable water wash, chlorination (NaOCl-200 ppm) followed by irradiation (2 kGy using electron beam or gamma) was developed, and the processed samples showed keeping quality up to 15 days at 4-6°C, whereas control samples spoiled within two days. The treatment resulted in coliform count below detection level while retaining the nutritional, phenolic content and organoleptic qualities. Thus, the combination treatment could ensure safety, keeping quality enhancement of perishable leafy greens and to control global food outbreaks. Electron beam over gamma processing found to be a commercial viable option due to its high throughput and equal efficacy in microbial decontamination

Differential gene expression in irradiated potato tubers contributed to sprout inhibition and quality retention during a commercial scale storage

Abstract Current study is the first ever storage cum market trial of radiation processed (28 tons) of potato conducted in India at a commercial scale. The objective was to affirm the efficacy of very low dose of gamma radiation processing of potato for extended storage with retained quality and to understand the plausible mechanism at the gene modulation level for suppression of potato sprouting. Genes pertaining to abscisic acid (ABA) biosynthesis were upregulated whereas its catabolism was downregulated in irradiated potatoes. Additionally, genes related to auxin buildup were downregulated in irradiated potatoes. The change in the endogenous phytohormone contents in irradiated potato with respect to the control were found to be correlated well with the differential expression level of certain related genes. Irradiated potatoes showed retention of processing attributes including cooking and chip-making qualities, which could be attributed to the elevated expression of invertase inhibitor in these tubers. Further, quality retention in radiation treated potatoes may also be related to inhibition in the physiological changes due to sprout inhibition. Ecological and economical analysis of national and global data showed that successful adoption of radiation processing may gradually replace sprout suppressants like isopropyl N-(3-chlorophenyl) carbamate (CIPC), known to leave residue in the commodity, stabilize the wholesale annual market price, and provide a boost to the industries involved in product manufacturing