Dados do Trabalho

Título

BIOACTIVE COMPOUNDS PRESERVATION IN STRAWBERRY BY APPLICATION OF EDIBLE COATINGS

Introdução

Strawberry (Fragaria x ananassa) is a non-climacteric pseudofruit with high economic importance and perishability. The use of techniques to increase their post-harvest shelf life has been extensively studied, and the application of edible coatings is an efficient possibility. However, only some studies have evaluated how bioactive compounds behave when applied to edible coatings. This study aimed to apply edible coatings containing arrowroot starch and natamycin to fresh strawberries and evaluate bioactive compounds' content during refrigerated storage.

Material e Métodos

Three treatments were developed (NR: strawberry without coating; RA: strawberry containing an edible coating of arrowroot starch; RAN: strawberry containing an edible coating of arrowroot starch and natamycin), which, after coating application, were stored for up to 12 days at 6°C. At the initial time and every three days, samples were evaluated for the content of total phenolic compounds, monomeric anthocyanins, and antioxidant activity using the DPPH, ABTS, and FRAP methods.

Resultados e Discussão

The anthocyanin content and total phenolic content increased significantly throughout storage (p<0.05), with RAN having a higher content (7.9 mg pg 3-glu/g and 20.4 mg GAE/g, d.b., respectively). The antioxidant activity on NR remained constant (p>0.05) at the initial and final times (118.8 umol TE/g for ABTS, 140.2 umol TE/g for FRAP, and 404.8 umol TE/g for DPPH) of storage. Similar behavior was observed for RA samples. However, for the RAN strawberry, an increase (p<0.05) in antioxidant activity was observed throughout storage, presenting, at the end of 12 days of storage, 190.6 umol TE/g for ABTS; 214.2 umol TE/g for FRAP and 574.5 umol TE/g for DPPH (d.b.).

Conclusão

Applying coatings on the surface of strawberries reduces the respiratory rate and delays gas exchange with the environment, reducing of phenolic degradation during storage. The presence of the antimicrobial natamycin contributed to less fungal growth in strawberries and a higher content of bioactive compounds. Applying a coating containing arrowroot starch and natamycin is promising for increasing the shelf life of strawberries and promoting an increase in the content of bioactive compounds in the product.