INVESTIGATIONS INTO THE PHYSIOLOGY OF VOLATILE AROMA PRODUCTION OF APPLE FRUITS

A restricted capacity for aroma volatile production of apple fruit is often observed if fruits are harvested prior to maturity or stored for an extend period of time in low O₂ and/or high CO₂ concentrations.
It appears that in the two cases, similar or identical physiological events may be responsible.
When such fruit are fed with various volatile precursors they immediately start producing high amounts of aroma volatiles, indicating that the enzymes needed for their production are present, while precursors are lacking.
Analysis of various lipid fractions yielded a good correlation between content of some unsaturated free fatty acids and volatiles production.
Further experiments employing (for example) inhibitors of fatty acid biosynthesis and desaturation suggest that these substances are limiting under the above conditions.
We propose that the failure in aroma production is caused by the impact of low respiration leading to depletion of metabolites (such as ATP, NADPH) required for fatty acid biosynthesis and desaturation.

International Postharvest Science Conference Postharvest 96

F. Bangerth, J. Streif, J. Song, A. Brackmann

https://doi.org/10.17660/ActaHortic.1998.464.26