Journal of Food Processing & Technology

Abstract

Post-harvest Shelf Life Extension and Nutritional Profile of Thompson Seedless Table Grapes Under Calcium Chloride and Modified Atmospheric Storage

Imlak M, Randhawa MA, Hassan A, Ahmad N and Nadeem M

Grapes are the fruits with highest rate of phenolic substances among all other fruits and vegetables but due to its enhanced susceptibility to Botrytis cinerea, its postharvest losses are also very high. In a country like Pakistan that has lesser advancement in post-harvest technological skills, a significant segment of this delicate fruit is lost. This study was conducted with an aim to minimize these losses by retaining healthy and attractive nutritional profile. Freshly harvested grapes after being sorted and graded were divided in three lots, two lots were immersed in aqueous solutions of 1% and 2% calcium chloride followed by modified atmosphere storage at 5% CO₂ level, and third lot was control sample that was simply dipped in tap water at ambient conditions, 80% relative humidity and 10 ± 1°C temperature was kept same for all three lots. After being analyzed at harvest, stored grapes were then analyzed for total polyphenols, firmness, acidity, total sugars, total soluble solids and total viable count at 4^th, 8^th and 12^th days of storage respectively. Overall results designated that grapes pretreated with 2% CaCl₂ stored at 5% CO₂ level retained maximum firmness, acidity and phenolic substances with minimum increase in soluble solid contents and significantly reduced incidence of browning caused by gray mold as compared to water washed control sample that was spoiled at the 8^th day of storage. Grapes were stored for 12 days and the effect of storage days on differently pretreated samples was analyzed.