On the viscosity behaviour of field bean protein isolates in dependence on their degree of acetylation.
The increase of apparent viscosity when protein concentration is raised becomes more and more distinctly pronounced with an increasing degree of acetylation and is displaced at lower protein concentrations. Investigations of the influence of temperature on viscosity behaviour are therefore carried out on the basis of comparable initial viscosity. 20 min heat treatment at different temperatures shows that above 40 degrees C the order of magnitude of the temperature-induced increase in viscosity depends decisively on the degree of acetylation. With an increasing degree of acetylation there is a comparably stronger increase in viscosity. An increase of viscosity is also linked to increasing duration of the heat treatment. The higher the degree of acetylation, the greater--related to a defined duration of heat treatment--is the growth of viscosity. During the heating phase in cyclical temperature tests a viscosity maximum is formed at 60 degrees C, which becomes more and more distinctly pronounced with an increasing degree of acetylation. From computerised evaluation of flow curves it is generally established that the complexity of flow properties increases with increasing degree of acetylation, increasing concentration of protein and the effect of heat.
Central Institute of Nutrition in Potsdam-Rehbrücke, Academy of Sciences of the GDR.
G
G
Schmidt
H
H
Schmandke
D000107:Acetylation; D010940:Plant Proteins / Q000032:analysis*; D013696:Temperature; D014783:Viscosity
D010940:Plant Proteins