Ultra-weak photon emission from roasted sesame oil at different roasting temperatures and different qualities [Japanese]

摘要

Roasted sesame oil has many different kinds of lignans such as sesamin, sesamolin, and sesamol, so sesame oils have very high oxidative stability. However, there arc few methods for evaluating the oxidative stability and other qualities. The purpose of this study is to estimate the quality of roasted sesame oil using ultra-weak photon emission. In this report, we investigated how roasting sesame seeds influenced the ultra-weak photon emission from its extracted oils. We also investigated how the ultra-weak photon emission was influenced by the quality change in accelerated degradation tests (120degreesC and 201/h aeration) and long-storage tests. The results were as follows. The sesame oil became dark and the amounts of sesamol increased when roasting temperature was raised. Ultra-weak photon emission from the sesame oils also became higher at higher roasting temperatures. Accelerated degradation test revealed, through ultra-weak photon emission measurement and quality analysis, that there were three chemical reaction phases during degradation of the sesame oil. First, the balance between the hydroperoxide production rate from oils and the hydroperoxide decomposition rate was unstable. Second, the balance became stable. Finally, the hydroperoxide production rate became very high. The photon emission from sesame oils decreased when the quality became poor in the second reaction phase. The photon emission decrease with quality degradation was a characteristic emission phenomenon for roasted sesame oils. And we also clarified that sesamol addition in the sesame oil was caused higher photon emission. These results demonstrated the possibility of quality evaluation of roasted sesame oil using ultra-weak photon emissions.