K. MIHALEV1, M. BULEVA2, I. PETKANCHIN2 and P. MOLLOV1
1 University of Food Technologies, BG-4000 Plovdiv, Bulgaria
2 Bulgarian Academy of Sciences, Institute of Physical Chemistry, BG-1113 Sofia, Bulgaria
K. MIHALEV., M. BULEVA, I. PETKANCHIN and P. MOLLOV, 2003. Electro-optic study on the electric surface properties of cloud particles of cloudy apple juice. Bulg. J. Agric. Sci., 9: 481–486
The electric polarizability and the electrophoretic mobility (resp. ς-potential) of cloud particles, obtained from cloudy apple juice by reproducible washing procedure, were determined in model suspensions (pH 3.5–5.5, Ionic strenght 3×10–4). The electric polarizability, calculated from electro-optic studies, and the ς-potential, increased with the pH increase, especially in the range from pH 3.5 to pH 4.5, which is of interest in juice technology. Moreover the electric light scattering measurements are more sensitive to the cloud particles electric state changes than the electrophoretic ones. The results obtained show that the electro-optics is a reliable method for studying the electric surface properties of cloud particles, which could be important for understanding the stability of cloudy apple juices.