Study on techno-functional properties of pecan flour with different lipid content

Abstract

Pecan flour, obtained from the solid residue left after walnut oil extraction, is rich in proteins, dietary fiber, and phenolic compounds with antioxidant properties. This study evaluates the techno-functional properties of pecan flour with varying lipid contents. Key parameters include color (L*, a*, and b* values), bulk density, oil absorption capacity (OAC), water absorption capacity (WAC), emulsifying activity (EA), and stability (ES). A two-way factorial design was used to assess WAC, EA, and ES while varying pH and NaCl concentrations. Low-lipid pecan flour (20.7% ± 0.51%) showed a higher OAC (3.990% ± 0.024%) and a light beige color, while high-lipid flour (68.7% ± 0.61%) had a dark brown color and greater bulk density (0.532 ± 0.003 g/mL versus 0.217 ± 0.005 g/mL). WAC increased significantly in low-lipid flour at higher pH and lower NaCl levels, whereas high-lipid flour required higher NaCl concentrations to optimize WAC. EA and ES peaked at intermediate pH and NaCl levels, with low-lipid flour demonstrating superior emulsion properties due to its favorable hydrophilic-hydrophobic balance. The study highlights the complex interactions between pH, NaCl, and lipid content, significantly influencing WAC, EA, and ES. These findings provide insights for optimizing the functionality of pecan flour in food formulations. Also, the research establishes pecan flour as a promising ingredient for enhancing water retention and emulsion stability in food systems, contributing to sustainable food innovations and offering the potential for further exploration in complex food matrices.