Functional properties of sweet potato flour and its role in product development: a review

Abstract

Producing food products from sweet potato flour are very feasible in worldwide due to wide availability, natural color, high-energy, low-protein, good biological activity in the human diet and low cost, as a result, become a key ingredient for the production of new products in the current global habitation. Sweet potato flours can be used for imparting desired properties, nutritional value, antioxidants, and natural color to processed foods and also used as thickeners and gelling agents. However, the paucity of information regarding the functional properties of the sweet potato flour greatly limits its exploitation. This review attempts at gathering data available on the functional properties of sweet potato flour, highlighting their unique properties and potential field of applications. A significant variation was observed in functional properties upon the variety and some processing methods. Also, the differences in the size of the granules and the various contents of starch, protein and amylose influenced functional characteristics such as viscosity, pasting temperature, gelatinization temperature, swelling power and solubility. The modified flours using steam and blanching are useful in food preparations to reduce paste thickness in food products such as confectioneries, as well as in pharmaceuticals industry as a drug binder and disintegrant as they exhibited high bulk density. Low-paste viscosity of the acetylated flour makes these flour to be used in formulations that require a high volume of solids. As thickening agents, enzymes modified that have high viscosity paste are good. The use of modified flours in food products would guarantee a suitable amount of digestible starch. This information can also be used to design protocols for the food processing industry, aiming at consumer's needs, such as diabetics and obese people who may benefit from low digestibility of starch. The range of characters and food developments observed makes the sweet potato flour amenable to different applications in food industries based on their properties. An awareness of their potential uses can help in large-scale cultivation of these crops and the production of flour from them.