Egg white with margarine, and xanthan gum, have been used to produce alternative breads from cassava flour fortified with 200 g kg-' soya flour. All the additives increased the amount of air entrapped in the cassava batters at the mixing stage, as indicated by their lower batter densities. The lower the batter density the higher was the maximum gas retention volume attained in the 60 min fermentation stage. However, final loaf volume also depends on the stability of the batter; egg white primarily acts as a stabiliser. Margarine, and more significantly egg white, reduced the extent of starch gelatinisation and solubilisation in the bread. Breads made with locally available egg white and margarine are sensorily acceptable to Nigerian consumers and have very good keeping qualities.

Abstract:Bread was made using a straight-dough baking process from a local soft wheat flour partially substituted at four levels with flour from nine different cassava (Manihot esculenta, Crantz) clones. The physicochemical properties of the blended flours, including starch quality, were determined and related to dough rheology, bread volume and crumb characteristics. Breadmaking quality at substitution levels of 100 and 200 g kg-' of mixed flour was reliably predicted from the cassava flour diastatic activity only. Flours with relatively high diastatic activities, ie above -145 mg of maltose, had deleterious breadmaking effects.Baking absorption effects were more critical at substitution levels of 300 and 400 g kg-'. Cassava flour diastatic activity was highly dependent on the moisture contents of the respective tuberous roots, and affected the extent of starch gelatinisation in the breadcrumbs.

Alternative (wheatless) cassava breads were made with cassava flour from eight different cassava (Munihot esculenta, Crantz) clones fortified with soya flour (200g kg-' total flour) using margarine and egg white, or xanthan, as additives. In this study, bread specific volumes were reliably predicted from only the diastatic activity and maximum paste viscosity of the cassava flour, although further variables still need to be investigated. Flours with diastatic activities above -145 mg of maltose, and indirectly low maximum paste viscosities, produced dense, pudding-like structures with completely gelatinised crumbs. The flour diastatic activity was dependent on the moisture content of the freshly harvested tuberous root; above a critical threshold moisture ( N 75 %) content the specific air intake of the loaves decreased sharply. The extent of starch gelatinisation and solubilisation did not critically affect loaf volumes but affected crumb structures.

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