36E-15 |
|
M. A. ROJAS-GRAÜ1, A. Sobrino-Lopez2, M. S. Tapia3, and O. Martín-Belloso2. (1) Dept. of Food Technology, UTPV-CeRTA, Univ. of Lleida, Spain, (2) Dept. of Food Technology, Univ. of Lleida, Av. Alcalde Rovira Roure, 191, Lleida, 25198, Spain, (3) Instituto de Ciencia y Tecnología de Alimentos, Univ. Central de Venezuela, PO Box 47097, Caracas, 1041-A, Venezuela Fuji apple is a variety that does not soften significantly during postharvest storage thus being well suited for minimal processing. The main cause of cut surface deterioration of Fuji apple slices is browning, and use of natural antibrowning agents is an alternative widely investigated. The objective of this work was to evaluate the effect alone or in combination of 4-hexylresorcinol (4-HR), glutathione, N-acetylcysteine and ascorbic acid on enzymatic browning of apple Fuji slices stored at 4º C packed in air with no modification of the atmosphere. Apples were cut into 4 mm thick slices and dipped for 1 min in different combinations of antioxidant agents. Samples were stored in plastic bags for 14 days. Enzyme was extracted and quantified by a spectrophotometric method. Enzymatic activity was the response variable studied in a central composite experimental design using response surface methodology. Among all the factors investigated, cysteine as independent factor (p<0.05), and the interactions of 4-HR with glutathione or with cysteine (p<0.05), and of ascorbic acid with glutathione (p<0.0001) or cysteine (p<0.05), showed a significant effect in the control of PPO activity. These results are shown in the surface response plots presented. Storage time had a marked effect in all experimental conditions.This study, using response surface methodology, demonstrated that browning can be avoided along refrigerated storage by an appropriate concentration and combination of natural compounds. It is necessary to examine the effects of these antibrowning agents on sensory, texture and nutritional quality attributes.
Session 36E, Fruit & Vegetable Products: General
2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana |