Nutritional and technological properties of the starchy fraction of carioca bean obtained by functionalized air classification by microwave and ball mill

Abstract

The use of natural resources needs to be rethought due to population growth and thus ensure that basic human needs are met with emphasis on food. An important legume in world food is the bean (Phaseolus vulgaris L.), being the variety of carioca bean the most cultivated in Brazil. The starch represents about 25 to 45% of the carbohydrates present in beans, arranged as semi-crystalline granules, with a high amylose content. This composition characterizes its structural and functional properties, such as swelling power and solubility in water; gelatinization, retrogradation, shear strength, and high resistant starch content. The resistant starch present in carioca beans has a high potential for application in formulations, due to its physiological effects similar to dietary fiber. Its use would allow the use of out-of-type and hardened grains that have low commercial value. In addition to resistant starch, mechanical damage to the starch granules during production can cause changes in their structure and functionality. The Indications that the physical method of double modification of starch granules has potential applications for bean starch. The dry fractionation is an alternative to the wet fractionation method that causes negative impacts on the environment due to the use of organic solvents and water resources. For legume fractionation, air classification can be used. In this technique, the flour is separated into two fractions, a fine fraction (protein) and a coarse fraction (starch). Flours rich in bean starch obtained by dry fractionation have different characteristics from those processed in conventional mills, such as, for example, the high content of damaged starch. In the dry fractionation process, starch results as a co-product of protein extraction, which is considered the most valuable fraction, although it is present in a smaller proportion. Therefore, knowing the nutritional and technological properties of this major fraction becomes essential to determine its application in foods and to enable the efficiency of the dry fractionation process. Thereby, the objective of this project is to characterize and evaluate the coarse fraction (starch) extracted from carioca beans by dry fractionation, regarding its technological and nutritional properties to encourage its application as an ingredient in food products.