Fat emulsions. Effect of polyoxyethylene and alkyl content of emulsifiers on stability to sterilization

Summary When a given system of emulsifiers of known compositions and molecular weights was employed, it was found that in order for fat emulsions of 15% oil content to be stable to the heat required for sterilization, the emulsifiers must meet definite requirements. Minimum weight percentage of total lipophilic groups should be 0.29%; minimum weight percentage of total hydrophilic groups should be 0.57%; the polyoxyethylene groups of emulsifiers containing such groups should account for at least 70% of the mole weight of these emulsifiers; the lipophilic/hydrophilic ratio should be about 0.5. The minimum content of lipophilic and hydrophilic groups was found to be an additive total of these groups as provided by the complete emulsifying system whether composed of individual or multiple emulsifying agents and whether of similar or dissimilar functional groups. With the emulsifiers used, an acyl group greater in length than 12 carbon atoms was found to be necessary to prepare cottonseed oil emulsions which were stable to heat. Resistance of emulsions to breakage by mechanical shock was imparted by a rather large amount of lipophilic groups, so that the lipophilic/hydrophilic ratio was 1 or over. Presented at fall meeting of American Oil Chemists' Society, Cincinnati, O., September 30–October 2, 1957. This work was supported in part by funds from the Office of the Surgeon General, U. S. Army. One of the laboratories of the Southern Utilization Research and Development Division, Agrciultural Research Service, U. S. Department of Agriculture.