Maintenance of postharvest quality of blackberry (Rubus fructicosus L.) fruits through salicylic acid and CaCl2 immersions

Blackberries (Rubus spp.) have significant nutraceutical properties, providing phenolic compounds for the consumers. These compounds are useful to human health due to their high antioxidant activity. However, most blackberries destined for fresh markets become unmarketable in 2 to 3 days due to decay and leakage, because they have thin and fragile skin. The present study was aimed to investigate the effect of salicylic acid (SA) and calcium chloride (CaCl2) on extending the postharvest quality and bioactive compounds of blackberry during refrigerated storage. Blackberry fruits cv. ‘Jumbo’ were dipped in 2% CaCl2, or in 2.0 mM salicylic acid (SA) for 10 min. Total soluble solids contents, titratable acidity, pH, ascorbic acid contents, total phenolics contents, and total antioxidant activity were investigated initially on 4th, 7th, or 10th day (d) of storage. Changes in fresh weight, titratable acidity, ascorbic acid and total phenol contents were markedly delayed by both treatments. Berries treated with 2 mM SA or 2% CaCl2 exhibited markedly better visual quality during the storage period. Considering the overall findings, this study revealed that postharvest SA or CaCl2 applications maintained the storage-life and conserved the valuable marketing features of blackberries over 10 d in cold storage, presumably due to their inhibitory effects on fruit senescence.