高温のフライ油中に存在する水とその制御

抄録

The quality control of frying oil and the management of cooking processes are critical to the taste of fried foods, and to the safety and economic efficiency of the commercial production of fried foods. The authors conducted research to assess the degradation of frying oil by studying its electrical properties and observed peculiar behavior of the dielectric constant believed to be caused by water present in the frying oil. An analysis of the dielectric constant suggested that water remains in high-temperature frying oil for a relatively long period of time. It is generally thought that water promptly reaches its boiling point of 100°C when added to high-temperature frying oil and is immediately discharged from the oil and into the atmosphere as steam. Verification that water indeed remains in frying oil at elevated temperature for long periods of time would indicate that there is a mechanism that hinders the discharge of water from high-temperature oil. Accordingly, in this paper we reproduce the conditions in which water remains in the frying oil and consider the factors causing this retention. We also discuss methods for extending the life of frying oils by controlling and managing the degradation of oil caused by hydrolysis when used frying oil is stored.