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In order to elucidate the temperature and pressure effect on the oil expression of perilla seed, recovery´ of expressed oil (REO) and volumetric strain of both roasted and unroasted perilla seeds were observed at different temperature, pressure and for different periods of press. In this experiment, moisture content of perilla seed was adjusted to 2.5% and temperature used were 30, 40, 50 and 60℃ . Pressure applied were 10, 30, 50 and 70 MPa, and periods of press were 5, 7, 9 and 11 min. As tert~perature and pressure were increased or periods of press was lengthened, REO and volumetric strain of pressed cake were increased. Maximum REO of unroasted perilla seeds were found to be 85.59% and those of roasted perilla seeds be 85.30%, at 70 MPa, 60℃, and for 11 min. Viscosity of expressed oil were exponentially dependent on temperature and REO were increased as viscosity was decreased. From statistical analysis between effects of expression factors and REO and volumetric strain of pressed cake, importance of their effects was decreased in the order of pressure, temperature. temperatureXpressure and periods of press. The multiple regression equation between REO(Y) and temperature (T), pressure (P), and periods of press (D) were as follows; Y=7.95+36.85P+1.12T²--0.55 TP-5.08P₂ r₂-0.97 for unroasted perilla seed (p$lt;0.01), Y=4.50T+39.23P+0.83T²-1.71P-5.07P²r²- 0.99 for roasted perilla seed (p$lt;0.01).
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