An improved method of obtaining fat or oil and feeding meal from fish, offal and thelike

摘要

Fat or oil and feeding meal is obtained from fish, fish offal, &c. by heating the material, pressing it for the extraction of oil and finally drying the pressed material. Before the fat or oil is pressed out, the water content of the raw material is reduced to 40 to 55 per cent. The material may be heated to 60-90 DEG C. before and/or after drying and pressed at that temperature. In the example given, herring is dried in an ordinary desiccator until its water content is about 45 per cent, in such a manner that its temperature on leaving the desiccator is 60-90 DEG C. Immediately afterwards, the material is pressed in a continuous screw press, leaving a residue containing about 4 per cent of fat and 40-45 per cent of water. The pressed material is then further dried and ground into meal and the oil purified in separators, centrifuges, &c. It is stated that the drying of the raw material to 40-55 per cent water content before pressing enables the oil to be extracted at lower pressures, that the fat content of the residue is very low, and that the loss of proteins in that water pressed out is reduced compared with normal practice.ALSO:Feeding meal is obtained from fish, fish offal &c. by heating the material, reducing the water content to 40 to 55 per cent, pressing out the oil, further drying the pressed material, and grinding it into meal. The material may be heated to 60-90 DEG C. before and/or after drying, and pressed at that temperature.