Study of physiological and molecular changes related with browning development on fresh cherimoya (Annona cherimola Mill.)
Reinaldo Campos-Vargas, Bruno G. Defilippi, Paula Romero, Hector Valdes, Alvaro Castro, Daniella Utz, and Humberto Prieto
Abstracts of 27th International Horticultural Congress & Exhibition (IHC 2006), August 13-19, 2006, COEX (Convention & Exhibition), Seoul, Korea. 494 pages.
2006
บทคัดย่อ
Cherimoya (Annona cherimola Mill.) are prone to browning when the fruits are wounded during minimal processing.Therefore, our study has been focused to understand the physiological basis of browning and the role of polyphenol oxidase enzyme (PPO) in this process.PPO activity apparently is related with ripening since mature fruits showed higher values than ripe fruit.In addition, the PPO activity in the rind was at least four times higher than the flesh, and there is a higher PPO activity in the flesh close to the rind than near the center of the fruit.At the molecular level, we have cloned a fragment of putative cherimoya PPO gene and experiments to study PPO expression in cherimoya tissues and fresh cut pieces are under way, as well as characterization of PPO promoters.As a technological approach we have assayed antioxidant treatments to prevent browning.The treatment with 0.5% cysteine applied just after processing has show promise in browning reduction in fresh cut cherimoya stored for 6 days at 0°C.The application of cysteine did not change soluble solids and acidity of cherimoya pieces, but the total phenolic compounds were modified (funded by FONDECYT 1040011).