Modeling the Rheological Behavior of Chemically Interesterified Blends of Palm Stearin/Canola Oil as a Function of Physicochemical Properties

The main aim of the current study was to model the rheological and textural properties of chemically interesterified palm stearin (PS)/canola oil (CO) blends as a function of saturated fatty acids (SFA), solid fat content (SFC), and temperature. The results and proposed models in this study can be used in design and development of new fat products by trying to limit the need for instrumental methods. To describe and predict how the viscoelastic properties and firmness of the blends change with SFA content, several models have been proposed. The firmness curves of fat samples were described as a function of (SFA, Firmness(f(SFA)), Rsqr = 0.94, and mean absolute error (MAE) = 1009.00 g) and (SFC20, Firmness(f(SFC20)), Rsqr = 0.98, and MAE = 750.80 g) using a one-variable Quadratic model. In the next step, a two-variable Quadratic function for expression of firmness as a function of both SFA content and SFC20 with high goodness of fit and low error (Rsqr = 1.00 and MAE = 0.00) was developed. The G ' modulus as a function of temperature (G '(f(T))) and SFC (G'(f(SFC))) curves was S-shaped and the three Sigmoidal functions (Logistic, Gompertz, and Sigmoid models) were well able to describe their properties. However, the Logistic models described the G '(f(T)) (Rsqr>0.99 and MAE < 7838.00 Pa) and G '(f(SFC)) (Rsqr>0.94 and MAE < 20,802.00 Pa) curves in the best way. Finally, a two-variable Logistic model considering both temperature and SFC as variables was developed and fitted on the experimental data with Rsqr of 0.97 and MAE of 85,367.56 Pa. The validation of the proposed models shows their efficiency and ability for prediction of rheological and textural values of various interestrified blends.