Use of riboflavin to reduce decay and extend the shelf-life of fresh-cut sweet pepper

Riboflavin (vitamin B2) generally is recognized as a safe (GRAS) additive. It is used in food to fortify products with low natural content or compensate for the possible vitamin losses during processing. In this work, we studied the effect of pre-storage riboflavin dips on the quality maintenance of fresh-cut pepper (Capsicum annum L). We initially tested the efficacy of different riboflavin concentrations (0, control; 1; 10 and 100 μmol L−1) to reduce spoilage in fresh-cut green sweet pepper sticks (5 × 1 cm). Treatments with 100 μmol L−1 riboflavin effectively controlled pepper spoilage and were therefore selected for further evaluation along with refrigerated storage. Riboflavin dips reduced soft-rot decay incidence and severity and prevented the increase in electrolyte leakage, and respiration during storage. Riboflavin treatments preserved textural properties by preventing tissue hardness, stiffness, and resistance to bend losses. Treated peppers also presented lower yeasts and molds and aerobic mesophilic bacteria counts. Finally, riboflavin-dips improved antioxidant and phenolics retention without alterations in color, weight loss, sugar, or organic acids. Taken together, results show, for the first time, that riboflavin may be used as a postharvest preservative agent to extend the shelf-life of fresh-cut vegetables.