The rheological behavior of native and high-pressure homogenized waxy maize starch pastes
- Authors: Wang, Bao , Wang, Lijun , Li, Dong , Wei, Qing , Adhikari, Benu
- Date: 2012
- Type: Text , Journal article
- Relation: Carbohydrate Polymers Vol. 88, no. 2 (2012), p. 481-489
- Full Text: false
- Reviewed:
- Description: Both steady and large amplitude dynamic rheological testes were carried out in hydrothermally gelatinized waxy maize starch (WMS) pastes. The concentration of WMS was maintained at 6.0% (w/w) throughout these tests. The WMS pastes exhibited shear thickening behavior during the first up curve in steady shear tests. The shear thickening behavior was found to be irreversible and could not be retained after equilibrating the pastes beyond 6 h. The change in the shape of Lissajous curves was insignificant during strain sweeps at higher angular frequencies. This arose because of slow response of WMS pastes to oscillatory strain within a period of oscillatory shear, which can be attributed to the domination of rheological properties by amylopectin in continuous phase. High-pressure homogenization (HPH) was found to significantly reduce the apparent viscosity of the WMS pastes. After HPH, the WMS pastes behaved like typical Newtonian fluids. © 2011 Elsevier Ltd. All rights reserved.
Effect of high-pressure homogenization on microstructure and rheological properties of alkali-treated high-amylose maize starch
- Authors: Wang, Bao , Li, Dong , Wang, Li-jun , Liu, Yan-hong , Adhikari, Benu
- Date: 2012
- Type: Text , Journal article
- Relation: Journal of Food Engineering Vol. 113, no. 1 (2012), p. 61-68
- Full Text: false
- Reviewed:
- Description: The effect of high-pressure homogenization (HPH) on the microstructure, rheological properties, paste clarity, as well as gel retrogradation behavior of alkali-gelatinized high-amylose maize starch (HMS) was investigated. The alkali-treated HMS pastes were subjected to HPH at homogenizing pressures of 25, 50, 75, 100, and 125 MPa. After HPH treatment, the uniformity in the microstructure of HMS pastes was greatly increased. At homogenizing pressures greater than 100 MPa, starch ghost particles were found to completely disappear. The apparent viscosity of the HMS pastes was found to decrease significantly due to the application of HPH. The paste clarity of the HMS pastes increased when HPH treatment was applied. After storing at 4 °C for 7 days, HMS pastes homogenized at 50 and 100 MPa displayed weaker viscoelastic behavior than their corresponding unhomogenized pastes. This indicated that HPH treatment is capable of inhibiting starch retrogradation in gels. © 2012 Elsevier B.V. All rights reserved.