Effects of pregelatinized waxy maize starch on the physicochemical properties and stability of model low-fat oil-in-water food emulsions

The effects of pregelatinized waxy maize starch (WMS) concentration (0.0-5.0 wt%) on the physicochemical properties and stability of model low-fat (20.0 wt% rapeseed oil) oil-in-water emulsions, made with dried egg yolk or sodium caseinate (2.0 wt%) were explored. All samples exhibited shear-thinning flow behavior, and the detected from HerscheleBulkley's model parameters: yield stress (tau(0)), consistency coefficient (K), and flow behavior index (n) were highly affected (p < 0.001) by WMS addition. Oscillatory test data revealed that the structure of emulsions changed from liquid (<= 2 wt% WMS) to gel-like (>= 3 wt% WMS). The storage (G') and loss (G '') moduli were modeled as a power function of oscillatory frequency. WMS concentration had a significant (p < 0.001) impact on the emulsions stability with respect to creaming and fat holding capacity. Positive correlation values were found between Bohlin's and stability parameters of emulsions. The obtained results can be exploited for the development of low-fat health-oriented food emulsions. (C) 2013 Elsevier Ltd. All rights reserved.