Improvement of shelf-life and nutrient quality of tomatoes and eggplant fruits using chitosan-starch composite coat

Abstract

Background. In developing countries like Nigeria, postharvest loss of fruits and vegetables have been a serious problem as they become unavailable outside their peak seasons due to poor preservation techniques. Methods. This study evaluated the improvement of the storage-life and nutrient retention of tomato and eggplant fruits via the application of chitosan-starch edible coat. The dip coating method was used to coat the fruit samples while standard procedures (AOAC methods) were applied in determining the shelf-life and nutrient quality of the fruit samples. Results. The results of the shelf-life study showed that the coated fruits were still fresh at day 12 of storage. A significant change in protein, fiber and carbohydrate content was observed for coated tomato (5.34, 3.2 and 26.55%, respectively) compared to the uncoated tomato (24.8, 11.4 and 62.77% respectively). There was a significant difference between the change in ascorbic acid content in coated (6.28%) and uncoated (17.11%) eggplant. In tomato fruit, a significant difference existed in the ascorbic acid content of the coated (0.59%) and uncoated (7.46%) fruit, as well as the beta-carotene level (0.81 and 7.98%, respectively). Conclusion. It is therefore noteworthy that edible chitosan–starch composite coating may be instrumental in curbing the challenges of fruit deterioration with concomitant retention of nutrients.