PURPOSE: To obtain a parched oil feedstock useful as a feedstock for e.g. flavoring oil excellent in flavor, by putting an oil feedstock except sesame seeds onto a substrate followed by irradiating the feedstock with far-infrared rays under specified conditions to efficiently treat it with improved heating efficiency.

CONSTITUTION: An oil feedstock such as various seeds (except sesame seeds), nuts or embryo buds, is put onto a substrate and parched by irradiating it with far-infrared rays from above and also from the substrate side, thus treating the feedstock. It is preferable that various flavoring oils be produced by squeezing this feedstock.