Ion-Exchange Chromatography of Egg Yolk

Abstract

MODIFICATIONS of egg yolk protein fractions caused by physical treatments such as pasteurization, freezing or spray drying have received little attention. The gelation of thawed frozen yolk, and the loss of some of the leavening, foaming, and emulsifying abilities of spray dried egg yolk are well known. Powrie et al. (1963) showed that the lipoproteins are affected by freezing. Saari et al. (1964) reported that the low protein lipoproteins of the yolk were specifically changed by freezing. The lipoprotein which was denatured by freezing was shown to contain a high percentage of free fatty acids. The mechanism of the gelation is not completely understood. Fevold and Lausten (1946) reported that lipovitellenin prepared by acetone drying is unstable in the dry form but after drying by lyophilization solubility was retained. The effect of spray drying on the yolk proteins has not been investigated. The heat sensitivity of various yolk protein fractions…