Effect of time of harvest and packaging on quality and shelf life of litchi fruit

Generally in India, postharvest operations such as sorting, grading and packaging of harvested litchi fruit are done at the orchard itself due to non-availability of pack-house at farm and nearby places. Considering the available facilities vis-à-vis prevailing harsh weather conditions during harvesting period and rapid changes in physiology of litchi fruits, a study was carried out during 2013-2014 and 2014-2015 with the objective to assess the effect of harvesting time and improved packaging technique on shelf life of litchi fruit. Mature fruits were harvested early in the morning starting from 4 to 12 am and grouped in three lots (up to 6, 9 and 12 am). Fruit quality parameters, viz., fruit weight, pericarp properties, anthocyanin content, respiration rate, TSS and acidity were analyzed. The fruits were packed in 2-kg ventilated CFB boxes using two types of perforated polymer lining material and kept at ambient condition (32±2°C and 49±2% RH) for one week. It was evident that the fruit lot harvested late in sunny day (10 am onwards) and packed traditionally (without polymer lining) showed rapid loss of pericarp moisture accompanied by visually perceivable pericarp browning within three days under ambient storage condition. Fruit harvested early in the morning (6 AM), kept in perforated mono-polymer bag and packed in 2-kg CFB boxes recorded least physiological loss in weight (6.8%), browning index, respiration rate (116.2 mL CO2 kg(-1) h(-1)) and maximum anthocyanin content 28.36 mg 100 g-1 peel) as well as marketable fruits (74%) after 5 days of storage at ambient condition. Fruit harvested in sunny hours (10 am onwards) and kept in perforated polymer bags and packed in CFB box resulted in 62% marketable fruits, after 5 days of storage. Thus based on the studies, it can be advised to harvest litchi fruits early in the morning and pack them in CFB boxes with perforated mono-polymer lining.