Ginger is a tropical Asian tuber plant, whose hot, spicy root has a pungent aroma. This root is somewhat like an agglomeration of radishes, except white in color. These can be found in the produce section of the supermarket. It is used primarily in cooking or as a medicine. Powdered root is sold as a spice, and we are familiar with its flavor in Ginger Ale.
Some years ago, we almost sold a screw press to Charles Jacquin et Cia. for extracting juice from Ginger. They use the juice in the production of a fine liqueur. Unfortunately, a large amount of suspended solids were present in the press liquor, and the cost of clarification precluded an economic operation. The machine was to have been sent to China.
Another customer, Royal Pacific Foods, in California, has since built a successful ginger product line. They import cargo containers of the root from China. The material arrives washed and packed in 30# net bags like those used for onions and potatoes.
Royal Pacific first shreds the root in a Corenco M12A angle shredder. The shredded material falls directly into a standard Vincent Model CP-6 screw press with a profile bar screen and 5-hp drive.
In pressing, ginger produces an extremely high yield of juice. Normally 75 to 80% by weight is converted into press liquor. (The press cake is discarded.) The press liquor is pasteurized and packaged in 5-gallon pails, which are frozen solid. The product is sold predominately to producers of oriental cuisine.
One set of operating data gave 1.5 gpm of press liquor and 500 pounds per hour of press cake, for a total feed into the press of 1,250 pph. That was with well-ground material being fed into a CP-6 press. The air pressure on the discharge cone was 80 psi and screw speed was 17 rpm.