Protection of methionol against oxidation by oxygen scavenger: An experimental and modelling approach in wine model solution
Résumé
The aim of this study was to evaluate the impact amount (1% and 3%) of oxygen scavengers (os) incorporated in a PET matrix on methionol oxidation in model wine solutions with different initial oxygen concentrations. At saturated oxygen concentration, the studied amount of oxygen scavenger did not affect the methionol preservation. In more realistic oxygen concentration of wine (0.117 mmol/L), methionol was only protected after contact with 3% of oxygen scavenger. For a minimal concentration of oxygen (0.024 mmol/L), the presence of scavenger slowed down the methionol degradation by 1.2 and 1.9 times for 1osPET and 3osPET respectively. For the strongest oxygen concentrations, a mechanistic model was proposed to predict methionol degradation in relation to scavenger amount. This model based on second order reactions for methionol degradation and oxygen consumption by scavenger fitted well with the experimental data. An improvement of this model has been developed for the low initial oxygen amount.