Richard H. Edwards

Factors Affecting Juice Extraction and Yield of Leaf Protein Concentrate from Chopped Alfalfa

ADSTRACTA twin screw press was used to dewater ground alfalfa feed material. The dewatering behavior of the ground alfalfa and the yield of leaf protein concentrate (LPC) were determined. Grinding signifi-cantly increased the extraction of juice, solids, and nitrogen from the feed alfalfa, the dry matter content of the resultant press cake, and the yield of LPC. The average yield of LPC was 15.2 percent of the ground alfalfa feed weight (dry basis), an increase of 62 percent compared to a chopped unground alfalfa control. The yield of LPC and other processing results were approximated by appropriate multiple linear equations. The yield of LPC was dependent on the temperature, dry matter, fiber and protein contents of the feed alfalfa. The yield of juice was dependent on the feed alfalfa fiber and dry matter contents.

Pilot-plant scale grinding and pressing of jojoba seeds

Jojoba seeds were successfully milled at ambient temperature using a modified 8 in. single disk attri-tion mill. Rates to 4000 lb/hr at low energy input (1.7 kwh/ton) were achieved. The oil was expressed with a laboratory screw press at yields from 27. to 33.6%. Multiple linear regression analysis showed the oil yield to be a function of the motor amperage and feed moisture content. The press throughput rate was a function of the motor amperage and the amount of fine and coarse particles in the milled feed.