Effects of UV-C treatment on quality and antioxidant parameters of minimally processed strawberries

AVALOS LLANO, KARINA ROXANA; SGROPPO , SONIA CECILIA; CHAVES, ALICIA RAQUEL

Foz de Iguazú, Paraná

Congreso; 16th IUFosT World Congress of Food Science and Technology. XVII Latin American Seminar of Food Science and Technology-ALACCTA.; 2012

International Union of Food Science and Technology (IUFoST) - Latin American and Caribbean Association of Food Science and Technology (ALACCTA)

It is necessary to develop technologies that improve the safety of fresh-cut products through microbial control, while they get to keep the main organoleptic and healthy properties of its components. Camarosa minimally processed strawberries were treated with UV-C radiation (5.8 KJ cm-2) and subsequently stored for 12 days at 0 °C to investigate their effects on microbial quality, titratable acidity, weight loss, reducing sugars and antioxidant properties. UV treatment resulted in initial reduction of 0.7 log units in the mesophilic aerobic bacteria count and the reduction was 1.2 units at 2 days of storage, but had no effect at day 12. It also found similar reductions in molds and yeasts counts. Treated samples showed titratable acidity 5% lower than controls during storage and weight loss slightly lower after day 6. Reducing sugars were initially decreased (18%) by treatment but then rose progressively with values slightly lower than controls but not significantly different. Antiradical power and ascorbic acid of controls decreased, whereas the treated samples remained its value during storage. Moreover, treatment did not affect total phenolics and flavonoids. Total anthocyanins increased reaching a peak on day 6 in controls, whereas those treated increased by 13% at day 2 but then remained constant until the end storage showed lower values than controls. The results suggest that the application of UV radiation (5.8 KJ cm-2) reduces the microbiological attack mainly during the first 8 storage days by maintaining its antioxidant properties which could be useful to improve postharvest storage of minimally processed strawberries.