ON EVALUATING THE EMULSIFYING PROPERTIES OF PROTEIN USING CONDUCTIVITY MEASUREMENTS

Selected oil-in-water emulsifying properties of alpha-lactalbumin, bet a-lactoglobulin and bovine serum albumin were evaluated at solution co ncentrations ranging from 0.1 to 20 mg/ml. Changes in emulsion conduct ivity were recorded during and shortly after homogenization, and inter preted for each protein in terms of properties related to emulsifying activity and emulsion stability. A new quantitative analysis of the pa ttern of the entire conductivity curve is described and defended as an improvement on current interpretation of emulsion conductivity data w hich considers only the initial slope in evaluation of short term emul sion stability. In a manner consistent with past research, emulsion st ability so calculated was found to increase with increasing concentrat ion. Moreover, differences in emulsion stability among the three prote ins were found to be consistent with known molecular influences on the ir surface activity at apolar interfaces.