Influence of wounding intensity and storage temperature on quality and antioxidant activity of fresh-cut Welsh onions

Abstract

Welsh onion (Allium fistulosum L.) is a very popular, medicinal and functional vegetable in East Asian countries. Welsh onion can be processed into different cuts and widely used as flavoring agent in food processing. In this study, the effects of wounding intensity (slices, pieces, and shreds) and storage temperature (4 and 20°C) on postharvest quality and antioxidant activity of fresh-cut Welsh onions were studied. Our results showed that increased wounding intensity and higher storage temperature both led to the sharp rise of respiration rate, and the increasing loss of pungency, soluble solids content and ascorbic acid. On the other hand, the increase of phenylalanine ammonia lyase activity, the accumulation of phenolic compounds and the enhancement of antioxidant capacity were intensified with increased wounding intensity and higher storage temperature. The shelf life of 4°C stored slices, pieces and shreds was determined to 5 d, while for 20°C stored samples, this threshold was shortened to 1.5, 1.5 and 1 d, respectively. Thus, our results suggested that increased wounding intensity and higher storage temperature reduce postharvest quality and shorten shelf-life, but increase antioxidant activity of fresh-cut Welsh onions.