Carbon dioxide assimilation during postharvest removal of astringency from persimmon fruit

Application of anaerobic conditions with CO2 or N2 atmospheres to remove astringency from harvested persimmon fruit (Diospryros kaki L. cv. Triumph), caused production of more acetaldehyde under CO2 than under N2, 14CO2 applied in a 100% CO2 atmosphere, for 48 h to astringent persimmon fruits was incorporated mainly into malate and very little into other metabolites, such as carbohydrate or amino acids. Application of malate or pyruvate to pulp discs of astringent persimmons caused an immediate rise in acetaldehyde production. The higher levels of acetaldehyde produced by whole fruits held in a CO2 atmosphere, than by fruits held in a N2 atmosphere, can be explained through fixation of atmospheric CO2 into malate, leading to acetaldehyde production.