ORIGINAL PAPER Effects of Cultivar and Drying Method on Color, Pasting and Sensory Attributes of Instant Yam (Dioscorea rotundata) Flours Kolawole O. Falade & Ngozi F. Onyeoziri # Springer Science+Business Media, LLC 2010 Abstract Effect of cultivar (Efuru and Abuja) and drying method (cabinet and foam mat) on color, pasting, and sensory properties of instant pounded yam flours was investigated. Color (L*, a*, b*) values of fresh and dried flour samples were measured, and deltachroma (ΔC), color difference (ΔE), and hue angle were calculated. Pasting properties of flour and sensory attributes of fresh and reconstituted flour were determined. Foam density of yam pastes decreased from 0.97 g/cm 3 to between 0.362–0.538 and 0.308–507 g/cm 3 for cultivars Abuja and Efuru, respectively. Foam-mat dried flour showed higher L*, ΔC, ΔE, and hue angle but lower a* and b* values. Peak viscosities of cabinet and foam-mat dried Abuja and Efuru were 217, 304, 377.42, and 316.50 RVU, respectively. Sensory attributes of reconstituted foam-mat dried Abuja and fresh pounded yam were not significantly different (p > 0.05). However, fresh pounded yam (8.5–8.9) and recon- stituted foam-mat dried flour (7.4–8.5) samples were significantly different (p >0.05) from the cabinet-dried (6.9–7.9) and commercial samples (7.2–7.8). Keywords Dioscorea rotundata . Yam cultivar . Color parameters . Pasting . Drying methods . Instant yam flour Introduction Yams (Dioscorea spp.) are important source of carbohy- drate for many people of the Sub-Saharan region, especially in the yam zone of West Africa (Akissoe et al. 2003). With over 150 species grown throughout the world (Purseglove 1991), yams contribute more than 200 dietary calories per capita daily for more than 150 million people in West Africa and serve as an important source of income (Babaleye 2003). Indeed, yams, grown principally for their carbohydrate content, account for about 20% of the daily caloric intake of Nigerians (Iwueke et al. 1983) and are known to have a long standing sociocultural significance in some communities (Degras 1993; IITA 2004). Fresh yams are highly perishable primarily as a result of their high moisture content (50–80% wet basis; Degras 1993; Falade et al. 2007). However, when dried and milled into flour, yam becomes a durable commodity that can be stored for several months. Yam flours, depending on the mode of preparation, are mainly consumed in form of amala and instant pounded yam. Pounded yam is one of the most important culinary traditional preparations of yam in Nigeria and, indeed, West Africa (Ajibola et al. 1988). Pounded yam is usually consumed with vegetable soup as an accompaniment, the latter supplying the necessary protein, fat, vitamins, and minerals requirement to make it a complete diet (Aiyeleye and Eleyinmi 1997). The process of traditional production of pounded yam involves peeling of the tuber, cutting of the peeled tuber into small pieces, washing of the pieces, and boiling until the pieces are fully cooked without being soggy. The boiled pieces are removed and immediately pounded while hot using a locally made wooden mortar and pestle until a stiff moldable dough is formed. Water is added intermittently during the pounding process. The product is called in different names in different localities. For example, it is known as yam fufu or foufou in some French African countries and Iyan in Yoruba-speaking parts of Nigeria and Dahomey (Komolafe and Akinoso 2005). The traditional process of pounded yam production as reviewed above is very K. O. Falade (*) : N. F. Onyeoziri Department of Food Technology, University of Ibadan, Ibadan, Nigeria e-mail: kolawolefalade@yahoo.com DOI 10.1007/s11947-010-0383-8 Food Bioprocess Technol (2012) 5:879–887 Received: 23 December 2009 / Accepted: 11 May 2010 / Published online: 3 June 2010