In vitro Digestibility of Starch from Ready-to-Eat Cassava and Corn Flours

Abstract

Slowly digestible starch (SDS) and resistant starch (RS) associate with health benefits when present in the diet. This study aimed to evaluate ready-to-eat corn and cassava flours regarding their commercial presentation (dry or flaked), composition and in vitro digestibility of starch. Sixteen samples from Southern Brazil were procured in the market: eight dry cassava flours, six biju-type (flaked) corn flours and two biju-type cassava flours. Dry cassava flours had higher L* and lower b* values, and higher RS, relative crystallinity and viscosity peak values. Dry cassava flour partially preserves granular starch, as its processing involves lower drying temperatures and lower moisture of the pressed pulp. Dry cassava flours that had higher b* values also had higher rapidly digestible starch (RDS) levels, since higher temperatures are required in their production. Both biju-type flours showed the highest RDS values and no RS due to processing with elevated temperature and high moisture of the pressed pulp. In this study starch digestibility from the flours depended on processing, with minor influence of the raw material, fiber content HIGHLIGHTS  Ready-to-eat flours, used without further processing, deliver raw starch to diet.  Dry cassava flour had the best starch digestibility profile from all samples. Processing of the flours influences starch gelatinization degree and digestibility. Consumption of cassava flour can benefit nutritional quality of a meal.

Nutritional composition and in vitro starch digestibility of Banku flour processed from cassava (Manihot esculenta Crantz) root and quality protein maize grains

“…In contrast, as the quantity of QPM flour increased from 10% to 50%, the resistance starch increased from 19% to approximately 73%. Higher levels of slowly digestible and resistant starch in all of the samples containing QPM flour could be attributed to the higher peak viscosity measured in all of these samples (Table 3), because viscous media slows down the mobility of α‐amylase, lowering the rate of digestion (Ma et al ., 2019; Piroski et al ., 2021). Also, higher crude fat levels recorded in these flour samples could lead to the creation of an amylose–lipid complex, making starch digestion more challenging.…”