Abstract: The present invention relates to an improved method for the modification of a food for a ruminant mammal such that the mammal will produce a modified milk fat or meat fat which method comprises:(a) producing an emulsion of(i) a non-toxic food substance to be encapsulated; and(ii) an acid sensitive nontoxic crosslinkable material which will surround and encapsulate the substance with the proviso that no added crosslinking chemical is present in the emulsion; (b) subjecting the emulsion to reaction conditions which crosslink the crosslinkable material and encapsulate the substance. Specifically, the method is useful to encapsulate emulsified unsaturated fatty acids with a natural protein such as whey protein concentrate containing a reducing sugar, such as lactose, with crosslinking and encapsulating using the Maillard browning reaction. Cattle sheep or goats feed the modified food produce a higher level of unsaturated milk fat and meat fat.