A coating containing phenolic extract from açaí seeds for the preservation of strawberries

Strawberries are highly perishable fruits due to their high metabolic activity and high moisture content, making it necessary to adopt technologies that extend their shelf life. In this context, active coatings incorporating natural phenolic compounds represent a promising alternative for postharvest preservation. The objective of this study was to develop and characterize a sodium alginate coating incorporating phenolic extract from açaí seeds and to evaluate its effectiveness in preserving refrigerated strawberries. The fruits were divided into three treatments: uncoated (NR), coated with alginate (ALG), and coated with alginate incorporating the extract (EXT). Mass loss was assessed daily, while color (CIELAB), total soluble solids (TSS), pH, and titratable acidity were determined on days 0, 3 and 5. Mass loss increased in all treatments, reaching 8,7% (NR), 8,56% (ALG), and 9,29% (EXT) on the fifth day. pH decreased during storage, while titratable acidity was highest in the EXT treatment, reaching 6,10 g of citric acid/100 mL on the third day. TSS increased in all treatments and, at the end of storage, did not differ among themselves (1,19–1,23 °Brix). The coating with the extract provided better preservation of lightness (L = 52,0) and hue (h = 56,0), indicating better maintenance of the fruit’s visual quality. Thus, the alginate coating incorporating phenolic extract from açaí seeds showed potential for preserving the physicochemical and visual quality of strawberries during refrigerated storage, although it did not reduce mass loss.