Inhibition of enzymatic browning in minimally processed okra

Abstract

The okra pertains to olericulture and it is very much appreciated due to its gummy texture and high nutritional value involving wide versatility in culinary practices. The objective of this work was to evaluate the effect of ascorbic acid (AA), citric acid (AC) and Ethylene diamine tetra acetic acid (EDTA) for browning inhibition in minimally processed okra. Five treatments were employed: AA 1%, AC 1%, EDTA 0.5%, AA 1% + AC 1% and control which did not have any chemical addition. The minimum processing of okra involved the selection of the material, washing, cutting into pieces (±2 cm), sanitization, addition of inhibitors and centrifugation. The products were arranged in polystyrene trays and wrapped using polyvinilchloride (PVC) film and stored at 5±1 ºC for a period of 12 days. The total soluble solids, water activity, browning index, internal and external luminosity and total phenols contents were analyzed at an interval of three days. The different chemical treatments and the storage time influenced all the variables, except that of the internal browning intensity and the total phenols content. The AC treatment was less effective in controlling the enzymatic browning when compared to other treatments employed in this work. The use of EDTA 1% and AA 1% resulted in minor losses in soluble solids content, reduction in water activity and in internal and external luminosity of okra. Minimally processed okra retained its fresh quality until 12 days of its storage. Treatments with either EDTA 0.5% or of the mixture of AA and AC both at 1% were efficient in inhibiting browning in the internal part of okra cut pieces, resulting also in the reduction of total phenols contents.