The purpose of this review was to profile the existing innovations in the value addition of agricultural by-products and suggest innovations that could yield more value-added products from the available agricultural by-products in Uganda. These by-products were from crops, livestock, fish and forestry sub-sectors. The review indicated 7.8 million tons from the crops’ subsector, 6.69 million skins and hides, 2280 million tons of cow dung and 390,550 tons of chicken dung from the livestock subsector, 36,000 tons from the fish subsector and 440,000 m3 of sawdust and offcuts from the forestry sub-sector. Current innovations in value-addition of agricultural by-products included the making of briquettes, organic fertilizers, biogas, biochar, pellets and organic pesticides from the crop subsector. Cow dung from the livestock is used for plastering walls of houses, used as fertilizer and used for the production of biogas. Chicken droppings are as well used as fertilizer and for production of biogas. Fish frames and skins are mainly consumed in smoked form whereas trimmings are usually rolled into fish balls and then fried for people to eat while the fats are used for frying the fish balls. Sawdust has been mixed with cement to make wood-cement composite bricks that reduce the overall weight of the building. It is also being used as feed in the Indigenous Micro-Organisms (IMO) technology in the production of pigs. Proposed innovations include the use of bones to produce soft tissue, buttons, knife handles and bone meal. Blood can be used in making adhesives and fertilizers while fish oil is a major dietary source of long chain omega-3 polyunsaturated fatty acids and so can be utilized to enrich different food products.
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