We investigated the effect of pre-storage exposure to shortwave ultra-violet (UV-C) light on the decay and quality of fresh strawberries. Fresh strawberries (cv. Kent, 25% to 50% red) were exposed to UV-C at doses of 0.25 and 1.0 kJ/m 2 and stored at 4 °C or 13 °C. UV treatment controlled the decay caused by Botrytis cinerea at both temperatures and extended the shelf-life of the fruits by 4 to 5 d. UV-treated fruits had a lower respiration rate, higher titratable acidity and anthocyanin content, and were firmer than the untreated fruits. The percentage of free sugars increased faster in UVtreated fruits at the beginning of the storage period. A lower electrical conductivity in fruits treated with 0.25 kJ/m 2 suggests a slower rate of senescence compared to the control. A higher electrical conductivity observed with 1.0 kJ/ m 2 suggests damage to the fruits. Overall, UV treatment at 0.25 kJ/m 2 appears to slow down the ripening and senescence of strawberry fruits stored at 4 °C.

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Shortwave ultraviolet radiation (UV-C) was tested for controlling natural infections and inducing resistance to fungal decay caused by Botrytis cinerea Pers.: Fr. (gray mold rot) in bell pepper [Capsicum annuum L. var. annuum (Grossum Group)] fruit. All UV-C doses tested (0.22, 0.44, 0.88, or 2.20 kJ·m-2) caused a reduction in the number of natural infections occurring during storage at 13 °C. A UV-C dose of 0.88 kJ·m-2 controlled most effectively natural infections in peppers stored at both 13 or 20 °C. Although UV-C was found to be highly germicidal to B. cinerea conidia exposed on agar or on fruit wounds, it did not prevent infection of fruit inoculated with the pathogen 24 hours before exposure to UV-C. However, fruit which were exposed to UV-C 24 hours before inoculation with B. cinerea had a lower percentage of infections. For this reason, UV-C appears to act mainly as an inducer of disease resistance in this crop rather than a sanitizing agent. UV-C was effective in inducing resistance to B. cinerea in fruit at various stages of maturity, from green to red. Disease resistance was also induced in fruit which had been stored for 7 days before UV-C treatment. The effect of UV-C doses was found to be additive as two successive exposures at 0.44 kJ·m-2 had an equivalent effect as one exposure to the optimal dose of 0.88 kJ·m-2. However, two successive exposures to 0.88 kJ·m-2 were less effective than one exposure to this dose.

BACKGROUND: Seafood processing generates significant amounts of solid and liquid waste in the environment. Such waste represents a potential source of high-value biomolecules for food, pharmaceutic and cosmetic applications. There are very few studies on the valorization of wastewaters compared to solid by-products. However, cooking waters are characterized by a high organic polluting load, which could contain valuable molecules such as proteins, pigments and flavor compounds. Snow crab (Chionoecetes opilio) processing is included among the most important processes in Canadian fisheries, although its cooking effluent composition is not well characterized. RESULTS:The present study concentrated and valorized the biomass in snow crab cooking wastewaters for the development of products for food applications. A membrane process was designed and optimized to concentrate the effluents. The chemical composition of the concentrates was analyzed, including characterizing the flavor profile compounds. The extracts were mainly composed of proteins (592 g kg −1 ) and minerals (386 g kg −1 ) and contained desirable flavor compounds. Their functional properties (solubility, water-holding capacity, oil-holding capacity) and antioxidant activities were also assessed, and their safety was verified. CONCLUSION: The cooking effluents generated by snow crab processing facilities, usually considered as waste, can be concentrated and turned into a natural aroma for the food industry.

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