|Perkins Veazie, Penelope
|CLARK, J. - UNIV. OF ARKANSAS
Submitted to: Food Quality Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/22/1998
Publication Date: N/A
Interpretive Summary: Often, blackberries are shipped at temperatures warmer than ideal and may even be held at room temperature for 24-48 hours before final distribution to supermarkets. This experiment was done to determine the shelf life and compositional changes occurring in blackberries exposed to ideal and simulated retail storage conditions. We found that 'Navaho' blackberries could be held up to 21 days at 2 C and up to 14 days at 2 or 5C followed by 2 days at 20C. 'Shawnee' blackberries could be held no longer than 7 days at 2C and exposure to 20C decreased the marketable fruit by 50%. Differences between the blackberry varieties was not due to sugar composition or acidity. Navaho is a very firm blackberry while Shawnee is quite soft. Differences in firmness most likely determine the shelf life of blackberries.
Technical Abstract: Navaho and Shawnee blackberries, representing firm and soft varieties, respectively, were subjected to simulated retail storage conditions. Fruit were stored up to 21 days at 2 or 5C. At 7 day intervals, subsamples were removed and held 2 days at 20C. Shawnee blackberries became leaky after 7 days of storage. Navaho fruit were of marketable quality after 14 or 21 days storage at 2 or 5C, but exposing fruit to 20C after 14 days storage accelerated deterioration. Titratable acidity decreased more rapidly in blackberries held at 5C or in fruit stored 2 days at 20C. Total amounts of sugar decreased very little during storage at any temperature. Sucrose was present in very small amounts in both Shawnee and Navaho and was quickly lost during storage, while fructose levels increased slightly. Data indicate that Navaho fruit can withstand much more temperature abuse than Shawnee and could be held as long as 21 days at constant 2C storage.