The effect of fermentation on physicochemical properties and oxalate content of cocoyam (Colocasia esculenta) flour was evaluated. The cocoyam, white flesh was cleaned, washed, peeled, sliced into chips of 2–2.5？cm thickness, soaked in tap water and left to ferment for 24？h and 48？h. The fermented cocoyam was then drained, dried in cabinet dryer at 60°C for 24？h and milled. The flour samples were passed through a 45？μm mesh size sieve. Unfermented cocoyam flour was also produced and served as a control. Calcium oxalate and some physicochemical properties of flours from the fermented cocoyam were compared with the unfermented flour. Results showed that fermentation effected a significant reduction in oxalate level (58 to 65%) depending on the fermentation period. The amylose content was higher in 48？h fermented flour (55.52%) than in 24？h (54.55%). Pasting (gelatinization) temperature decreased, and water absorption capacity increased markedly due to fermentation. 1. Introduction Cocoyams are the third most important root crop (after yam and cassava) cultivated in West Africa. More than three quarters of the world cocoyam production come from Africa with Ghana and Nigeria being the world’s leading producers [1]. They are also important crops in Hawaii, Japan, and Egypt [2]. In general, they are stem tubers that are widely cultivated in both the tropical and subtropical regions of regions of the world [3]. Among seven species of Colocasia (taro) which originated from Asia and about forty species of Xanthosoma (tannia) from America, the two species mostly grown in West Africa are Colocasia esculenta and Xanthosoma sagittifolium [3, 4]. The Xanthosoma sagittifolium variety in Nigeria is hard and highly starchy which makes it easy for fufu preparation while Colocasia esculenta, with a softer tuber is usually prepared and eaten like yam. It produces a more floury starch suitable for use in composite mixture for food preparations. In some Nigerian diets, the cormels and young leaves of the taro variety serve as leafy vegetables [5]. Cocoyams can also be processed in several ways to produce food and feed products similar to that of potatoes in the Western world. Among the processes cocoyam can be subjected to, are boiling, roasting, frying, milling, and conversion to “fufu”, soup thickeners, flour for baking, chips, beverage powder, porridge, and speciality food for gastrointestinal disorders [5–8]. Several studies have shown that cocoyams contain digestible starch, protein of good quality, vitamin C, thiamin, riboflavin, niacin, and high scores of amino acids
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