Effect of edible coating in physical-chemical parameters in minimally processed cactus pear (Opuntia ficus-indica)

The purpose of this research was to study the effect of two edible coatings on the shelf-life of minimally processed cactus pears. Foodcoat® (F) and Pomfresh® (P) as standalone treatments or in combination (P+F), compared with un-treated fruit, were tested. F is an edible coating composed of fatty acids derivatives and polysaccharides in an alcohol solution, while P is composed of a mixture of organic acids and antioxidants. The fruits were peeled manually, immersed for 3 s in each emulsion and placed, in numbers of three, in easy-to-open polylactic acid (a biodegradable polymer) trays with a sterile adsorbent material and stored for 4, 8 or 12 days at 5°C. Physical-chemical analyses (texture, color, pH, titratable acidity and total soluble solids), microbial growth, taste characteristic, visually appearance and in-package CO2, O2 and ethylene were carried out. Changes in chemical parameters (pH, acidity and ascorbic acid) were affected by treatments and edible coating composition. The taste analysis showed that the control fruit and those treated with P coat scored better than those subjected to different treatments, especially for their appearance and texture. Although the lid of the trays was not hermetically sealed, gas movement was drastically restricted, generating an average in-package CO2 partial pressure of about 5.0 kPa in uncoated fruit and fruit treated with P coat and 5.7 kPa in fruit treated with F and P+F coat. All treatments reduced microbial growth compared to uncoated fruit.