Broken rice rejected in the milling process, barley, maize, and cassava meal are commonly used as feeds in Thailand. The use of these residues may be considered a form of bioconversion in common practice throughout the world. Where cellulosic materials have high lignin components, digestion by animals is minimal. In such cases, a small amount of fermentable carbohydrates such as corn meal or molasses is added to produce silage, thus ensuring rapid fermentation. Silage making normally serves as one of the effective means of conserving high-moisture products for animal feed.
Many crop residues are deficient in protein and minerals.
It is therefore not uncommon for farmers to add products such as urea and minerals at the time of ensiling. Fermentation of carbohydrate residues for human consumption is negligible in Thailand. Biogas production in Thailand has not received adequate attention. Recently, some attempts have been made to promote this type of bioconversion. There has been increasing interest in the productive utilization of agricultural and agro-industrial residues throughout the world.