Pig rind is one source of collagen for processing into products, such as sausage casings and films. However, it has a high fat content. The invention produces a defatted collagen paste from a collagen source by cutting the collagen into pieces, pressurising the collagen pieces to squeeze out fat and disintegrating the defatted pieces to form a fibrous paste. The paste can be used to produce a gel, which may be extruded to produce a collagen product.