A study published in the Journal of Agricultural and Food Chemistry has found that minimal processing of certain fruits, i.e. cutting up and chilling-does not significantly affect its nutritional content even after 6, and up to 9, days.
In practical terms, this means that you can prepare a bowl of fruit salad on the weekend, store it in the refrigerator, and enjoy it for about a week, receiving most of the nutritional benefits of just prepared fruit salad.
In the study, researchers cut up pineapples, mangoes, cantaloupes, watermelons, strawberries and kiwi fruit. The freshly cut fruits were then rinsed in water, dried, packaged and stored at 41°F (5°C).
After 6 days, losses in Vitamin C were less than 5% in mango, strawberry, and watermelon pieces, 10% in pineapple pieces, 12% in kiwifruit slices, and 25% in cantaloupe cubes. No losses in carotenoids were found in kiwifruit slices and watermelon cubes. Cantaloupe, mango, and strawberry pieces lost 10-15%; pineapples lost the most at 25%.
No significant losses in phenolic phytonutrients were found in any of the fresh-cut fruit products.
Lead researcher Maria Gil explained:
"Contrary to expectations, it was clear that minimal processing had almost no effect on the main antioxidant constituents. The changes in nutrient antioxidants observed during nine days at five degrees Celsius would not significantly affect the nutrient quality of fresh cut fruit. In general, fresh-cut fruits visually spoil before any significant nutrient loss occurs."
Gil MI, Aguayo E, Kader AA. Quality changes and nutrient retention in fresh-cut versus whole fruits during storage. J Agric Food Chem. 2006 Jun 14;54(12):4284-96. 2006.