Castor seed harvested from field is dried till the pods open. Seeds are hulled by using de-hullers or by hand to remove the seed from the pod. Extraction of oil from castor seeds is done in a manner similar to that for most other oil seeds. The ripe seeds are allowed to dry. These seeds are cleaned, cooked and dried prior to extraction. Cooking is done to coagulate protein (necessary to permit efficient extraction). The first stage of oil extraction is pre-pressing, using a high pressure screw press – called the expeller. Extracted oil is filtered and the material removed from the oil is fed back along with fresh material. The Indian variety of castor has an oil content of 42-48%.

Castor seed harvested from field is dried till the pods open. Seeds are hulled by using de-hullers or by hand to remove the seed from the pod. Extraction of oil from castor seeds is done in a manner similar to that for most other oil seeds. The ripe seeds are allowed to dry. These seeds are cleaned, cooked and dried prior to extraction. Cooking is done to coagulate protein (necessary to permit efficient extraction). The first stage of oil extraction is pre-pressing, using a high pressure screw press – called the expeller. Extracted oil is filtered and the material removed from the oil is fed back along with fresh material. The Indian variety of castor has an oil content of 42-48%.