Maintenance of fresh boysenberry fruit quality with UV-C light and heat treatments combined with low storage temperature
Sommaire de l'article
Mature boysenberries (Rubus hybrid) were harvested, heat-treated (45degreesC for 1 or 3 h or 47degreesC for 1 h) or exposed to UV-C light (2.3,4.6 or 9.2 kJ/m²), and stored at 20degreesC for 2 d. Fruit treated with 9.2 kJ/m² or 45degreesC for 1 h showed less damaged drupelets per fruit and/or remained firmer than untreated fruit after 2 d. Those treatments were selected for further analyses. In another experiment, boysenberries were either UV-C (9.2 kJ/m²) or heat-treated (45degreesC for 1 h) and stored either at 20degreesC for 1 d or at 0degreesC for 4 d before transfer to 20degreesC for 1 d. Both UV-C and heat treatments reduced softening and/or fruit damage. Treated fruit had lower respiration rates and anthocyanin leakage than control fruit suggesting greater tissue integrity. Titratable acidity, PH, total sugar content and antioxidant activity in treated fruit showed fewer changes than in control fruit when stored at 20degreesC for 1 d. Results suggest that beat or UV-C treatment, alone or in combination with refrigerated storage, may be a useful non-chemical mean of maintaining boysenberry fruit quality and extending postharvest life.