The influence of gentle processing of orange sweet potato on quality properties of purees

Abstract

Ipomoea batatas L. represents one of the most important tuber crops, after potato, and could be a real aid in preventing food insecurity, and malnutrition or sustaining a healthier lifestyle. Four thermal treatments were used to process the raw sweet potatoes into ready-to-eat products: boiling, steaming and steaming coupled with ohmic heating at two different voltage gradients (17.5 V/cm and 20 V/cm). Proximate composition, phytochemicals content, color parameters, viscosity, and texture as the main quality properties of the orange sweet potato purees were determined. The sample processed through steaming coupled with ohmic heating registered higher values for the total phenolic content (4.60±0.30 - 5.15±0.15 mg GAE/g DW) and total flavonoids content (7.07±0.41 - 7.66±0.88 mg EQ/g DW), compared to the control sample (4.33±0.28 mg GAE/g DW for the and 4.52±0.30 mg EQ/g DW, respectively), when determining the phytochemical profile. Among all the applied heat treatments, the mastication process was significantly improved when combining steaming with ohmic heating. These results are promising for developing new ready-to-eat products containing high nutritive tubers.