DETERMINATION OF PROTEIN-CONTENT OF WHEY POWDER USING ELECTRICAL-CONDUCTIVITY MEASUREMENT

A new method was developed to determine the protein content of commerc ial whey powder using electrical conductivity (EC) measurement. This m ethod is based on a multi-point measurement technique and a mathematic al model that can identify the contributions of protein and non-protei n constituents to EC. Twenty-four samples were analysed separately by the Kjeldahl and EC methods under different conditions. A significant correlation (r = 0.96) was observed and no significant difference was found between these two methods (P < 0.05). The results demonstrate th at the protein content of whey powder can be estimated by measuring ch anges in the conductivity of its dilute solution. (C) 1998 Elsevier Sc ience Ltd. All rights reserved.