Commercial pasteurised liquid whole egg was spray-dried, both alone and mixed with liquid milk, and some of it was frozen. Paper electrophoresis revealed that lipoprotein fractions from the pasteurised liquid egg were mainly immobile, in contrast to unpasteurised new-laid egg which contained both mobile and immobile lipoprotein fractions. The major difference between the soluble proteins of the commercial chilled pasteurised liquid egg and those of the same egg after freezing and thawing was the presence, in the former, of an inert lipoprotein fraction, amounting to 3.6% of the total egg solids and containing 88% lipid. The "soluble" proteins of spray-dried egg and egg-milk mixture also included large "inert" lipoprotein fractions eluted with the void volume.They contained 72-81 % of lipid and accounted for 7-13 % of the total egg solids. Larger fractions were eluted by the stronger salt buffer solutions and by hydrochloric acid from the dried egg-milk mixture than from the dried egg, and these were probably derived from the milk. All the spray-dried samples possessed the "inert insoluble" protein fraction characteristic of liquid egg, and the presence of a high molecular weight lipoprotein fraction was confirmed in each case. The "insoluble proteins" of the spray-dried samples had higher protein contents than those from the original chilled liquid egg and the thawed frozen egg.