Light-induced modulation of aroma, sugars, and phenolics in strawberries (Fragaria × ananassa Duchesne) during cold storage

Strawberries rapidly lose nutritional quality after harvest. Ultraviolet (UV) light provides a residue-free alternative to chemical treatments, but wavelength-dependent physiological effects remain underexplored. While UV-C is well recognized for its antimicrobial action, UV-B can stimulate phenolic metabolism and antioxidant defenses yet has been rarely examined in postharvest. Here, pre-storage UV-B and UV-C, with or without photosynthetically active radiation (PAR), were applied to strawberries for 7-day storage. UV-B increased anthocyanins after day 1, enhanced antioxidant activity, maintained sugar-to-acid ratio, and promoted key fruity esters. In contrast, UV-C lost 24-40 % more weight than control and delayed phenolic accumulation until day 7, particularly with PAR. Multivariate analysis revealed strong correlations among anthocyanins, antioxidant activity, sugars, and aroma, indicating coordinated light-regulated metabolic responses. Overall, UV-B outperformed UV-C in preserving strawberry quality, bridging a critical gap in wavelength-specific postharvest responses and highlighting UV-B as a promising non-chemical strategy for light-based preservation.