Thermal Oxidation of 9'-cis-Neoxanthin in a Model System Containing Peroxyacetic Acid Leads to the Potent Odorant beta-Damascenone

摘要

The potent odorant beta-damascenone was formed directly from 9'-cis-neoxanthin in a model system by peroxyacetic acid oxidation and two-phase thermal degradation without the involvement of enzymatic activity.beta-Damascenone formation was heavily dependent on pH(optimum at 5.0)and temperature,occurring over the two sequential phases.The first was incubation with peroxyacetic acid at 60 deg C for 90 min,and the second was at above 90 deg C for 20 min.Only traces of beta-damascenone were formed on application of only one of the two phases.Formate and citrate solutions produced a much better environment for beta-damascenone formation than acetate and phosphate.About 7 mug/L beta-damascenone was formed from 5.8 mg/L 9'-cis-neoxanthin under optimal experimental condition.The detailed pathway by which beta-damascenone is formed remains to be elucidated.