A preliminary study on the effedts of hydrocooling on quality of fresh longan fruit cv. Daw
Wittaya apai; Vicha sardsud and Uraporn sardsud
20th Biennial Conference of the ASIAN ASSOCIATION FOR BIOLOGY EDUCATION “Roles of Modern Technologies in Biology Education”. Chiang Mai University. Chiang Mai, Thailand. 27-30 December 2004. Page 32
2004
บทคัดย่อ
A preliminary study on the effedts of hydrocooling on quality of fresh longan fruit cv. Daw
One day old fresh longan fruit (Dimocarpus longan Lour. cv. Daw) was used in our preliminaty study. The fruits were placed in 3 kg perforated plastic baskets of commercial scale for each treatment. The treatments were: no pre-cooling; tap water immersion; pre-cooled with iced water plus no chlorine, with iced water plus 50 or 100 or 200 ppm chlorine respectively; for cooling time of 10 min until their final temperatures of longan fruit reached 5°C to determine the effects of hydrocooling treatments on quality and decay during storage at 5°C and 93 %RH. After three week storage the results indicated that iced water plus 50 ppm chlorine longan fruit treatment significantly decreased peel browning and decreased fruit decay in comparison with no pre-cooling and tap water immersion (the control). Pre-cooling plus 50 ppm chlorine which had maintained the highest L* value both inner and outer peel, prevented peel desiccation, maintained both total soluble solids (TSS) in flesh, sensory evaluation and extended storage life of longan fruit. Higher chlorine concentration: 100 or 200 ppm increased peel browning and fruit decay. Pre-cooling with no chlorine did not prevent fruit decay from fungi. Weight loss was not significantly affected by all treatments.