Influence of milk on the rheological behaviour of cross-linked waxy maize and tapioca starch dispersions

The influence of the addition of milk on the pasting behaviour, the flow and the viscoelasticity of dispersions of three medium cross-linking modified starches was studied. Viscosity values registered after heating and after cooling and the increase of viscosity during cooling ran parallel to the increase in starch concentration in both media, and for the same starch level they were higher in milk systems. These increases also depended on the type of starch. All samples exhibited shear-thinning behaviour and most of them showed time dependent flow behaviour (thixotropy or antithixotropy). The substitution of milk for water originated an increase on both yield stress and apparent viscosity at 1 s(-1) values that was different depending on starch concentration but similar for all starch types. Most samples showed a clear gel-like behaviour, the storage modulus being higher than the loss modulus. Both moduli values increased with starch concentration and were higher in milk systems, also depending on starch type. (c) 2005 Elsevier Ltd. All rights reserved.