Apples are popular due to their freshness and nutritional quality but tissue browning decreases both aesthetics and nutritional value of fresh apples. Enzymatic browning caused by polyphenol oxidases (PPO) is the second largest cause of quality loss in fruits and vegetables due to its negative effect on color, flavor, and taste. Tissue browning product(s) are the results of phenolic compound oxidation that are inherent to the apple tissue. It was established that PPO’s catalyze oxidation of phenolic compounds to corresponding quinones and subsequently to melanin resulting in the brown coloration. However, the identity of the quinones remains somewhat elusive. In order to understand the mechanism of browning, we investigated apple tissue oxidation products using enzyme tyrosinase (a PPO) in an ex vivo model. The phenolic oxidation products were extracted, purified and analyzed using high performance liquid chromatography with photodiode array detection. We will present detailed methodologies and results.

Ex vivo characterization of tissue browning products using apple (<i>Malus spp.</i>) as a model system

251st National Meeting (2016)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.

Ex vivo characterization of tissue browning products using apple (Malus spp.) as a model system