INFLUENCE OF GUAR GUM ON THE DISTRIBUTION OF SOME FLAVOR COMPOUNDS INACIDIFIED MILK-PRODUCTS

Acidified milk samples containing 0.1 to 0.5% guar gum were prepared w ith concentrations of milk fat from 0 to 20% and SNF from 6 to 12%. Th e partition coefficients of acetaldehyde, ethanol, and diacetyl were d etermined by headspace analysis using gas chromatography in samples th at were acidified to pH 4.5 at 30 and 50 degrees C. Guar gum did not a ffect the partition coefficients of the flavor compounds under any exp erimental condition. At both temperatures, the partition coefficient o f acetaldehyde was affected by the concentration of acetaldehyde and t he interaction of SNF and acetaldehyde concentration. The lowest parti tion coefficients of acetaldehyde were observed at 9% SNF under variou s experimental conditions. The concentration of ethanol and the intera ction of mills. fat and ethanol concentration affected the partition c oefficient of ethanol at both temperatures. The partition coefficient of ethanol increased as ethanol concentration and SNF increased. Milk fat, concentration of diacetyl, and the interaction of SNF, fat, and d iacetyl concentration affected the partition coefficient of diacetyl a t 30 degrees C. The partition coefficient of diacetyl increased as SNF increased. At 50 degrees C, concentration of diacetyl was the only si gnificant factor. Partition coefficients for ethanol and diacetyl were similar at 30 degrees C; however, at 50 degrees C, the partition coef ficient of diacetyl was higher than the partition coefficient of ethan ol. The partition coefficient was largest for acetaldehyde at both tem peratures.