Effect of temperature and aggregation rate on the fractal dimension of renneted casein aggregates

Abstract

This study deals with the influence of chymosin/casein ratios and temperature on the fractal dimension of renneted casein aggregates in diluted milk. The angular dependence of static light scattering, from 50 to 110°, was used to determine fractal dimension from double logarithmic plots of intensity versus scattering vector. No significant effect was observed when varying chymosin/casein ratios from 3.3 to 79.2 μg of chymosin/ g of casein at 30°C with a resultant fractal dimension value of 2.20. Temperature, on the other hand, influenced the aggregation mechanisms with fractal dimension values equaled to 2.32, 2.22, and 2.15 at 25, 30, and 35°C, respectively, for a chymosin/casein ratio at 13.2 μg of chymosin/g of casein. The importance of hydrophobic interactions in fractal aggregation of renneted casein particles is discussed.