THE RELATIONSHIP BETWEEN CHLOROPHYLL FLUORESCENCE AND FRUIT QUALITY INDICES IN ´JONAGOLD´ AND ´GLOSTER´ APPLES DURING RIPENING

A study was conducted to characterize the relationship between chlorophyll fluorescence (CF) and quality indices in apple fruit.
Fruit of ‘Jonagold’ and ‘Gloster’ apples were harvested at commercial CA storage maturity.
Half of the fruit were treated with 1-MCP for 16 hours at 22°C. Fruit were stored at 22°C. Untreated fruit were sampled every 7 days for 35-42 days, while 1-MCP treated fruit were evaluated every 14 days for 84 days.
CF parameters, Fo, Fv, and Fm, as well as fruit quality indices, firmness, soluble solids (SS), titratable acidity (TA), SS/TA, and aroma production were measured on eight individual fruit at each sampling period.
Significant relationships between CF and the fruit quality parameters, firmness, TA, SS/TA, and aroma volatile content were found.
Among the CF parameters, Fm, Fv, Fv/Fm, Fv/Fo, and Fo/Fv showed a significant relationship with the quality parameters of firmness, TA, SS/TA, and butyl acetate (BA) and 2-methylbutyl acetate (2MBA) content.
No significant relationship was found between CF and SS. Treatment with 1-MCP did not alter the relationship between CF and most quality parameters in ‘Gloster’. In ‘Jonagold’, the relationship between CF and firmness was weaker in 1-MCP treated fruit compared to untreated fruit.
Results indicate CF can provide a meaningful non-destructive measure of internal quality.
The relationship between CF and firmness, TA and SS/TA is promising and may lead to the development of a non-destructive fruit quality detector to sort fruit based on eating quality prior to fruit being shipped to consumers.

V International Postharvest Symposium

J. Song, L. Fan, C.F. Forney, K. McRae, M.A. Jordan

Malus x domestica Borkh., eating quality, non-destructive detection, firmness, volatiles, titritable acidity, flavor

https://doi.org/10.17660/ActaHortic.2005.682.184