ARS | Publication request: Cultivar Variation in Apple Fruit Firmness and Texture During Maturation, Ripening and Storage

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: March 13, 2008
Publication Date: N/A

Technical Abstract: Firmness and texture dynamics of apple cultivars ('Delicious', '’Fuji’, ‘Gala’, Golden Delicious', 'Honeycrisp', and ‘Pink Lady’) with a range of maturation and ripening characteristics were instrumentally assessed. Apples were harvested on multiple dates during maturation, and fruit from a harvest at or near physiological maturity were stored in air or a controlled atmosphere. The influence of ethylene action on firmness and texture was assessed by treated some fruit with 1-MCP prior to storage. Parameters measured using whole fruit with a section of peel removed included firmness in the outer and inner cortex, creep (material relaxation under constant load), and viscoelasticity. Signal processing was used to generate an estimate for fruit crispness. Cultivar-specific patterns were identified that indicate changes in inner cortex firmness, creep, crispness and/or viscoelasticity occur in the absence of outer cortex softening. The reverse pattern, decreased outer cortex firmness without change in one or more of the other parameters measured, also was observed. Postharvest treatment with 1-MCP and/or storage in a controlled atmosphere also differentially impact these firmness and texture parameters. The results indicate a range of firmness and texture patterns is discernable during development of the cultivars evaluated and that additional measures of apple physical properties identify changes during development that are not apparent with a measurement of outer cortex firmness alone.