PARTIAL DEFATTING OF ROASTED PEANUT MEALS AND KERNELS BY SUPERCRITICAL CO2 USING SEMICONTINUOUS AND INTERMITTENTLY DEPRESSURIZED PROCESSES

Roasted peanut kernels were ground into meal and subjected to supercri tical carbon dioxide (SC-CO2) defatting using a semicontinuous process (SCP). The amount of oil recovered from meal increased with increased pressures and temperatures from 3000 to 8000 psi and from 40 to 80 de grees C. When SCP and an intermittently depressurized process (IDP) we re applied at 8000 psi and 80 degrees C, the amount of oil recovered f rom roasted, deskinned kernels was less than that recovered from roast ed peanut meals. When IDP was done at 80 degrees C and various CO2 pre ssures, the amount of oil recovered decreased with a pressure reductio n from 8000 to 4000 psi and increased with a further reduction to 2000 psi. The breaking intensity of kernels partially defatted by IDP was significantly less than that of full-fat kernels. The fatty acid compo sition of SCP-extracted oils from peanut meal differed insignificantly , while that of IDP-extracted oils from peanut kernels differed slight ly depending on extraction conditions. Infrared and Raman spectra of t he oils extracted from kernels using SCP or IDP did not vary significa ntly.