portions of the dough with their fingertips and dip them into a 

 stew (8). Fufu is extremely popular throughout West Africa, 

 where it is made not only from yams but from other starchy 

 foods, such as cassava, plantains, and cocoyams. 



Yams are also boiled. They may be served in pieces or 

 mashed, alone or with a sauce or gravy. In soups or stews, pieces 

 may be used, or mashed yam may be added as a thickener. 

 Mashed yam may also be formed into cakes and fried. 



Yam tubers may be cut into thin slices or strips to be cooked 

 in the style of potato chips or french fries (18). However, not all 

 cultivars are suitable for this use because frying produces a bitter 

 flavor. 



Instant yam flakes are prepared by peeling, cooking, mixing 

 in a slurry, and drum drying (12). The flakes can be stored for 

 long periods and reconstituted by adding hot water or milk. The 

 product is highly acceptable, but quality depends on the use of 

 appropriate cultivars. Some D. rotundata cultivars are good for 

 this purpose, but D. cayenensis is not recommended because of its 

 yellow color. 



An interesting alternative to yam flakes is yam flour, which 

 is made by grinding cooked, dried tubers. The technology is 

 reported by Jarmai and Montford {13). The flour can be stored 

 for long periods and used to make fufu and mashed yam. It may 

 also be substituted for part of the wheat flour in baking bread 

 and pastry. D. alata has been studied more extensively in this 

 respect than D. rotundata, but the latter is probably the most 

 used. Better home and factory methods are needed both for the 

 preparation and the use of the flour, as this could constitute an 

 effective way to utilize yams through the entire year. 



COMPOSITION 



The dried weight of the edible portion of the tuber varies 

 from about 13 to 36 percent of the whole-tuber weight. Tubers 

 from the first harvest of D. rotimdata usually have low dry 

 weights. The mature tuber of most cultivars is quite dense. 

 Density, however, is a varietal as well as a physiological trait. 



The major part of the dry weight can be accounted for by 

 starch, which varies, with the dry weight, from about 10 to 28 

 percent. In addition to starch, the dry weight includes cellulose 

 or fiber, about 9 percent; protein, about 5 percent; sugars, 2 to 

 3 percent; and fatty materials, less than 1 percent. 



The starch of D. rotundata and D. cayenensis is rather coarse 

 {22). The individual granules are large and triangular, the 

 average measuring 10 to 70 micrometers in length. In addition, 

 a typical starch preparation contains a very large number of very 

 fine grains, but these make up a very small percentage of the 



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