The production of aquatic animals, aquaculture, is currently the fastest growing animal production sector in the world. The rapid expansion of the aquaculture industry is most pronounced in Asia, which contributes about 90% of the total global aquaculture production (by weight). This increase in aquaculture production must be supported by a corresponding increase in the production of formulated diets for the cultured aquatic animals. For most aquaculture systems, the cost of feed constitutes 30% to 60% of the operational costs of the farm, with protein being the most expensive dietary component. Even though fish meal continues to be used as a major source of dietary protein in commercial aquafeeds, its escalating cost have stimulated much research into the use of alternative plant protein sources (El-Sayed, 1999). Among the plant proteins tested, soyabean meal has enjoyed the most commercial success. Tropical countries import a large volume of soyabean meal for use as a source of protein in the production of animal feeds.