Effect of Storage Temperature and Packaging Material on Shelf Life of Thornless Blackberry

Abstract

Blackberry is a highly perishable fruit and its quality decreases very quickly during postharvest period. In this research, two types of container including: oriented poly styrene (OPS), a petroleum-based material, and oriented poly corn starch (OPCS), a bio-based material, was analyzed over 14 days to determine their effects on shelf life of thornless blackberry. Packages were placed in freezer (0˚C), refrigerator (4˚C) and room (25˚C) temperatures in a factorial format based on completely randomized design. Results showed a strong positive correlation between fruit weight and marketability (R2 = 0.726). It was confirm that fruit weight loss and shriveling can be an important reason for marketability reduction in blackberry. Blackberries were survived for 14 days at 0˚C, 8 days at 4˚C and only 3 days at room temperature. A downward trend was observed for pH, TA and TSS during the storage as well as for fruit taste and visual color. Fruits TSS was decreased regardless of the packaging materials and storage. Blackberries that were kept in OPS had significantly higher marketability and lower weight loss in comparison with OPCS that caused a reduction in fruit visual color and marketability. Results indicated that OPCS permeability caused higher fruit weight loss in comparison with other treatments. Blackberries in OPCS container had the highest amount of phenolic components following 14 days at 0˚C, which was significantly more than amount of phenolic components of fruits in OPS container. Compared to OPS, OPCS container did not make any improving in its characteristics to reduce fruit water loss that can be possible by using Nano clay particles.