| Abstract
| - The influence of high-pressure treatment (HPT) (200−800 MPa, 5 or 20 min, at 20 °C) on therheological properties of solutions of amidated low-methoxyl pectin (LMP) and its mixtures with micellarcasein (MC) has been investigated in the presence and absence of sucrose. The storage modulusG‘ of LMP gels containing 0−55 wt % sucrose and 0.1−1 wt % LMP was found to increase significantlyfollowing HPT at ≥400 MPa. Various concentrations of LMP in the presence of different amounts ofMC (0.5−12 wt %) showed contrasting types of rheological behavior. In the presence of a lowconcentration of LMP (<0.3 wt %), HPT was found to induce a sol−gel transformation at relativelyhigh LMP/MC molar ratios (<4 wt % MC), to reduce values of G‘ and the loss modulus G‘ ‘ atintermediate LMP/MC ratios (4−10 wt % MC), and to increase the values of G‘ and G‘ ‘ at low LMP/MC ratios (>10 wt % MC). In contrast, in the presence of a higher amount of LMP (>0.5 wt %), itwas observed that HPT enhances the values of both the storage and the loss moduli over the wholerange of MC concentrations. Keywords: Low-methoxyl pectin; micellar casein; high-pressure treatment; rheology; calcium ions;mixed biopolymers; dynamic mechanical testing
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