Application of high-pressure homogenization to tailor the functionalities of native wheat starch

BACKGROUND: The effect of high-pressure homogenization (HPH) on the rheological and thermal properties, water retention capacity (WRC), morphology and in vitro digestion of wheat starch was evaluated. Starch suspensions (50 g kg−1, w/w) were treated at increasing pressures (up to 100 MPa) and numbers of cycles (up to 5) to generate a wide range of energy densities (70–500 MJ m−3) delivered to the sample during processing. RESULTS: High-pressure homogenization induced a partial starch gelatinization confirmed by higher digestibility. Gelatinization degree (GD) was between 13% and 83%, causing a wide range of functional properties. High-pressure homogenization-treated starch samples showed WRC values of 810–1910 g kg−1. Storage modulus (G′) and complex viscosity (η*) of starch dispersions were almost two and three times higher than the control at 13% and 83% GD, respectively. Positive linear relationships between GD (R = 0.98, P < 0.001), WRC (R = 0.87, P < 0.05), or rheological parameters (R = 0.89÷0.90, P < 0.01) and energy density of HPH treatments were found. CONCLUSION: High-pressure homogenization treatment represents a promising technology to obtain wheat starch with tailored rheological properties and digestibility, which allows the texture and glycemic response of food products to be adjusted. © 2020 Society of Chemical Industry.