Effect of Hot Water Treatment on Astringency Removal in Persimmon Cultivars

Abstract

ABSTRACT The aim of this study was to investigate the effect of hot water treatments on the removal of astringency in ‘MKU Harbiye,’ ‘Kaki Tipo,’ and ‘Vainiglia’ persimmon cultivars. Fruits were dipped in tap water at hot water at 40°C for 5 h (HW 40°C-5 h) or hot water at 50°C for 1 h (HW 50°C-1 h). Untreated (Control 1), 20°C for 1 (Control 2, 20°C-1 h), or 5 h (Control 3, 20°C-5 h) and treated fruits were then kept at 20ºC for 10 days of shelf life period. Changes in weight loss, appearance, firmness, total soluble solids, taste, fungal decay, fruit skin color, soluble and insoluble tannin content were determined during shelf life. In all cultivars, HW 40°C-5 h was found to be successful in reducing the astringency and maintained firmness above the marketability limit for 10 days of shelf life period. The fruit treated with HW 40°C-5 h became edible after 7 days at 20°C while control fruits remained astringent based on soluble tannin content the entire shelf-life period. Although the HW 50°C-1 h and Control 2 and 3 (20°C-1 h or 20°C-5 h) treatments received acceptable taste scores after 10 days, fruits from these treatments were slightly astringent.