Replacement of wheat flour by other kinds of flour in bread making is economically important in South East Africa as wheat is mainly an imported commodity. Cassava is widely available in the region, but bread quality is impaired when large amounts of cassava are used in the bread formulation. Effect of differently processed cassavas (sun-dried, roasted and fermented) on composite cassava-wheat-maize bread quality containing cassava levels from 20 to 40% (w/w) was evaluated in combination with high-methylated pectin (HM-pectin) added at levels of 1 to 3% (w/w) according to a full factorial design. Addition of pectin to cassava flour made it possible to bake bread with acceptable bread quality even at concentration as high as 40%. In addition to cassava concentration, the type of cassava flour had the biggest effect on bread quality. With high level of cassava, bread with roasted cassava had a higher volume compared with sun-dried and fermented. The pectin level had a significant effect on improving the volume in high level roasted cassava bread. Crumb firmness similar to wheat bread could be obtained with sun-dried and roasted cassava flours. Roasted cassava bread was the only bread with crust colour similar to wheat bread. 1. Introduction Bread is an important staple food in South East Africa, providing energy and many nutrients such as proteins, B-vitamins, vitamin E, and minerals. Traditionally in Mozambique, bread is produced by a mixture of wheat flour, yeast (Saccharomyces cerevisiae), salt, and water. As wheat is not grown in Mozambique, large quantities are therefore imported at high costs for the country. In order to cut the nation’s expenses, the Government of Mozambique has thus mandated the use of composite flour in breadmaking including flour of cassava, maize, or millets that are locally available. There is a growing interest in using composite flour for breadmaking owing to some economic, social, and health reasons. However, the partial substitution of wheat flour by other flour types presents considerable technological difficulties because their proteins lack the ability to form the necessary gluten network for holding the gas produced during the fermentation [1–3]. The dough formed is more difficult to handle, and the bread has poor loaf volume and crumb softness [4]. Composite flour with cassava has been evaluated in breadmaking, and general observations are reduced loaf volume, crust colour, and impaired sensory qualities as the level of substitution of wheat with other flours increased [5, 6]. Similar results were reported by Khalil
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