Autor: |
Kiani H; Department of Food Science and Technology, Faculty of Agricultural Engineering and Technology, Campus of Agriculture and Natural Resources, University of Tehran, Karaj, Iran., Mousavi ME, Mousavi ZE |
Jazyk: |
angličtina |
Zdroj: |
Food science and technology international = Ciencia y tecnologia de los alimentos internacional [Food Sci Technol Int] 2010 Dec; Vol. 16 (6), pp. 543-51. Date of Electronic Publication: 2010 Nov 22. |
DOI: |
10.1177/1082013210367511 |
Abstrakt: |
Fluid gels are known to be very shear-thinning materials with yield stress. In this study, the rheological properties of gellan and gellan-pectin fluid gels in fermented dairy drinks were evaluated using viscometric measurements. Both gellan- and gellan-pectin-containing solutions showed the rheological properties of fluid gels resulting in stabilization of particles; but no evidence of a fluid gel was observed for those with pectin alone and those with no hydrocolloid content. Unlike pectin, gellan gum was capable of creating significant values of yield stress and accordingly stabilized colloidal particles and extrinsic added solid particles in the fermented dairy drink. However, pectin improved the stability in combination with gellan. The origin of fluid gel formation was assumed to be both permanent interactions occurring between gellan and proteins, forming hairy particle gels and transient interactions between the particle gels. The significance of yield stress values for particle stability was demonstrated and two methods, including a noteworthy infinite apparent viscosity method and a conventional Bingham approach, were employed to calculate the values of yield stress. Both the methods showed a good application potential due to their simplicity, reasonable results and also wide availability of the instrument applied. |
Databáze: |
MEDLINE |
Externí odkaz: |
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