Original scientific paper
Rheological properties of whey proteins concentrate before and after tribomechanical micronization
Zoran Herceg
; Prehrambeno-biotehnološki fakultet, Pierottijeva 6, 10000 Zagreb
Vesna Lelas
Suzana Rimac
Abstract
Hydrocolloids are long-chain polymers, used in food production at small quantities (from 0,05 to 5 %) to achieve appropriate rheological properties, prevent syneresis, increase the viscosity and stability of foodstuffs and for crystallization process control. The aim of this work was to investigate the influence of tribomechanical micronization of powdered whey protein concentrate on the rheological properties of whey proteins model systems as well as the influence of several carboxymethylcellulose hydrocolloids addition in such systems. Measurements were done using rotational viscosimeter, Brookfield DV-III at temperature 20 ºC. The rheological parameters were determined by powerlaw model. The results of investigation have shown that all investigated systems are non-Newtonian. Depending on the pretreatment of whey proteins and the mass fractions of hydrocolloids they exhibited pseudoplastic or dilatant properties. Particle size analysis was performed using Fritsch – laser particle sizer “analysette 22”. The operation of tribomechanical micronization caused the decreasing of particle size and incrasing specific area of whey proteins. Tribomechanical treatment of whey proteins had significant influence on the rheological parameters and the type of flowing.
Keywords
rheological properties; carboxymethylcellulose; whey protein concentrate; tribomechanical micronization
Hrčak ID:
1886
URI
Publication date:
18.4.2001.
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