摘要
Cocoyams (old-taro: Colocasia esculenta;newtannia: Xanthosoma sagittifolium) yield corms as root crops produced in regions of tropical and subtropical developing countries. In certain countries such as Ghana, there are surpluses in production but deficits in cereals. Cocoyams are used in a range of indigenous foods. Post harvest losses are high due to mechanical damage of corms during harvest and microbial attacks on such damaged corms during storage. Cocoyams contain, on average, 25% starch (wet weight basis) with A-type structures characterized by small granule size (<1.5 μm). Non-starch polysaccharides in cocoyams confer gummy properties to the starch. However, mechanical effects of raphides—crystals of calcium oxalate and other components—produce irritation when raw corm tissue is ingested resulting in several levels of discomfort. With appropriate processing, cocoyams could be a rich source of starch for food and industrial applications and corms have potential for new product development. Stabilizing cocoyam crops and adding value could greatly improve its utilization in cocoyam producing countries.
Cocoyams (old-taro: Colocasia esculenta;newtannia: Xanthosoma sagittifolium) yield corms as root crops produced in regions of tropical and subtropical developing countries. In certain countries such as Ghana, there are surpluses in production but deficits in cereals. Cocoyams are used in a range of indigenous foods. Post harvest losses are high due to mechanical damage of corms during harvest and microbial attacks on such damaged corms during storage. Cocoyams contain, on average, 25% starch (wet weight basis) with A-type structures characterized by small granule size (<1.5 μm). Non-starch polysaccharides in cocoyams confer gummy properties to the starch. However, mechanical effects of raphides—crystals of calcium oxalate and other components—produce irritation when raw corm tissue is ingested resulting in several levels of discomfort. With appropriate processing, cocoyams could be a rich source of starch for food and industrial applications and corms have potential for new product development. Stabilizing cocoyam crops and adding value could greatly improve its utilization in cocoyam producing countries.
