FATE OF ANTIOXIDANTS IN FRESH-CUT PRODUCE: PROCESSING AND STORAGE CONDITIONS TO MAXIMISE RETENTION
Fruits and vegetables are rich sources of antioxidants, compounds considered protective against a range of degenerative diseases including cancer and heart disease. Ascorbic acid, carotenoids, and phenolic compounds are the main antioxidants present; levels of these vary with produce item and cultivar. For example, there are major differences in antioxidant levels among lettuce types. Concerns have been expressed about possible losses of antioxidants in fresh-cut produce as a result of processing and storage. However, processing and storage cause complex effects. Processing can result in an increase in general metabolism due to the mixing of previously compartmentalised enzymes and substrates, and labile compounds such as ascorbic acid can be lost. Polyphenoloxidase converts phenolic compounds to ortho-quinones, and these are converted back to phenols with the loss of ascorbic acid. The extent of this loss is dependent on the level of tissue disruption, gas atmosphere, temperature and other factors. Processing and storage can also induce stress response-type reactions which may lead to de novo synthesis of some antioxidant compounds. We have seen this in increasing levels of carotenoids and phenolic compounds during storage. Severity of processing, washing treatments, gas atmospheres and temperature all affect antioxidant levels. Antioxidant levels found in the laboratory are compared with those in commercial products, and recommendations are made for optimal processing and storage.
O'Beirne, D. and Kenny, O. (2009). FATE OF ANTIOXIDANTS IN FRESH-CUT PRODUCE: PROCESSING AND STORAGE CONDITIONS TO MAXIMISE RETENTION . Acta Hortic. 837, 35-40
minimal processing, modified atmosphere packaging, ascorbic acid, carotenoids, phenols, vegetables, fruits.