The invention provides a process for producing a plurality of biomoleculeproducts fromby-products of animal food processing. The process includes the steps ofmixing the by-productswith one or more digestive enzymes in the presence of an acid to promotehydrolysis of the by-product to release the biomolecules, thereby providing ahydrolysismixture. The hydrolysis mixture is subjected to a density-based fractionalseparation,thereby providing an oil fraction, a liquid fraction and a solid fraction.Then the liquidfraction is separated from the oil and solid fractions and filtered with amolecular masscutoff filter, thereby providing a peptide product and a glycosaminoglycanproduct. The oilfraction may be further refined to provide an oil product and the solidfraction may befurther processed to provide bone-derived products such as gelatin, ossein andcollagen.
