Defatted flours, oilseed processing

Whole oilseeds and legumes and their derivatives (defatted flours, and protein concentrates and isolates) are used in traditional foods as sources of protein and for their texture-modifying functions. This article reviews, on a comparative basis, processes for preparation of vegetable food proteins, compositions and characteristics of the resulting food ingredients, and their functionalities and uses in traditional foods. 

A flowsheet for preparation of glandless cottonseed full-fat kernels and subsequent processing of defatted flours and concentrates and isolates is shown in Figure 1. This scheme, with specialized adaptations depending upon oilseed species, is typical for processing of all oilseeds. 

Use of some oilseed proteins in foods is limited by flavor, color, and flatus effects. Raw soybeans, for example, taste grassy, beany, and bitter. Even after processing, residues of these flavors may limit the amounts of soybean proteins that can be added to a given food (87). The use of cottonseed and sunflower seed flours is restricted by the color imparted by gossypol and phenoHc acids, respectively. Flatus production by defatted soy flours has been attributed to raffinose and stachyose, which are removed by processing the flours into concentrates and isolates (88). 

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