Evaluation of physico-chemical parameters of minimally processed apples packed in non-conventional modified atmosphere

Abstract

Modified atmosphere packaging (MAP) with non-conventional gas mixtures in combination with non-sulphite dipping was tested during refrigerated storage on minimally processed (MP) apple slices for the physico-chemical characteristics. `Golden Delicious' apple slices were dipped in an aqueous solution of 0.5% of ascorbic acid (AA), 0.5% of citric acid (CA), and 0.5% of calcium chloride (CC) to slow down the enzymatic browning. Apple slices were sealed in polypropylene boxes and conditioned in air (control) and in three different modified atmospheres (MAs) composed of 90% N 2, 5% O 2, 5% CO 2 (A), 90% N 2O, 5% O 2, 5% CO 2 (B) or 65% N 2O, 25% Ar, 5% O 2, 5% CO 2 (C). The packed apple samples were stored at 4 °C for 12 days and pH, soluble solids content, weight loss, CO 2 production, O 2 consumption, texture changes, surface colour (whitening index, hue angle and chroma) and percentage of browning area were monitored. Beneficial effects of B and C MAP were found on enzymatic browning together with an increase of initial firmness and total soluble solid content. Atmospheres with high argon and nitrous oxide levels are shown some beneficial effect on the product quality during the 10 days period of storage, compared to control.