Effect of blends of short and long-chain inulin on the rheological and sensory properties of prebiotic low-fat custards

Long-chain inulin (TEX) and short-chain inulin (CLR) combined in different proportions (25:75, 50:50, and 75:25) were added (7.5 g/100 g) to low-fat custards and their rheological and sensory properties were studied. The effect of the inulin blends on the rheological properties depended on the presence of λ-carrageenan (0.01 g/100 g). Slight variations were observed when inulin blends were added to custards without λ-carrageenan, whereas in samples with carrageenan, there was an important increase in thixotropy, consistency and elasticity. In both cases (samples with and without carrageenan), the differences perceived by assessors indicated that the blends 50:50 and 25:75 TEX:CLR were those affording greater thickness, sweetness and vanilla flavour intensity to the custards. Addition of inulin blends to low-fat samples did not manage to fully emulate the rheological behaviour of full-fat custard. However, the low-fat sample with the inulin blend 50:50 TEX:CLR added was perceived to have the same creaminess and thickness as the full-fat sample. The use of this blend combined with carrageenan gave thicker, creamier custard, which was preferred over the full-fat custard.