Action of Emulsifers in Promoting Fat Destabilization During the Manufacture of Ice Cream

Abstract Several emulsifiers have been examined in ice cream processing to determine their relative emulsion destabilizing power. The hydrophilic lipophilic balance value of the emulsifier did not account for all of the differences in destabilization; however, destabilizing power corresponded with the resulting interfacial tension between the serum and lipid phases of the mix. Fat destabilization results from the combination of ice crystallization and shear forces during ice cream manufacture. Neither shear nor ice crystallization alone were sufficient to cause the magnitude of destabilization encountered in a typical barrel freezer. It has also been shown that polyoxyethylene sorbitan monooleate, the most powerful destabilizing agent, reduced the amount of protein adsorbed to the fat globule surface. Thus, it is suggested that, based on their ability to lower the interfacial tension, emulsifiers control the adsorption of protein to the fat globule surface. The fat globules thus become more susceptible to coalescence induced by the shear forces of agitation and ice crystallization during ice cream manufacture.