Cultivar and Storage Temperature Effects on the Shelflife of Blackberry Fruit

Abstract

Arapaho,’ ‘Choctaw,’ ‘Navaho’ and ‘Shawnee’ blackberries ( Rubussp.) were stored at constant temperatures of 2°, 5°, or 10°C for 21, 14, or 7 days respectively, to determine shelflife. ‘Navaho’ consistently had fewer leaky berries than ‘Choctaw’ or ‘Shawnee’ for all storage intervals and temperatures. ‘Arapaho’ and ‘Navaho’ had a high percentage of firm berries (77 to 86%) after storage at 5 or 10°C. All fruit held in storage at 10°C prior to freezing had fewer red berries than fruit held at 2°C. At all storage temperatures, ‘Arapaho’ and ‘Navaho’ berries were more marketable, and had a higher soluble solids/titratable acidity compared to ‘Choctaw’ and ‘Shawnee.’ Of the four cultivars, ‘Navaho’ had the fewest red berries after freezing. In all cultivars, titratable acidity declined, pH increased, and soluble solids remained the same for berries held 7, 14, or 21 days at 10, 5, and 2°C, respectively. Total sugars were not different among cultivars and declined slightly during 21 d storage at 2°C (550.6 and 426.2 mg/g dw, respectively). Initially, glucose, fructose, and sucrose were present in all cultivars (46.6,48.3, 5.1%, respectively). After 21 d storage at 2°C, glucose levels increased slightly (to 54.5%), fructose levels decreased (to 45.5%), and sucrose declined (to 0%). The excellent shelflife of ‘Navaho’ and ‘Arapaho’ blackberries indicates that fruit of these cultivars should be suitable for long distance shipment.