Effect of emulsifier type on sensory properties of oil-in-water emulsions

This work investigates the fundamental properties of emulsifiers that may contribute to the fat-associated sensory attributes of emulsions. Model oil-in-water emulsions were prepared with 0, 12, 24, 36 and 48% oil and emulsified with seven different emulsifiers; two proteins; sodium caseinate and whey protein, and five different sucrose esters. Emulsions were rated for perceived ‘fat content’, ‘creaminess’ and ‘thickness’ on nine-point category scales. Instrumental measurements of particle size, viscosity, thin film drainage, surface dilational modulus and interfacial tension were made. The sensory results indicate significant main and interactive effects of fat level and emulsifier type. At higher fat levels, emulsions prepared with sodium caseinate and whey protein emulsifiers had higher viscosities and higher sensory scores than those prepared with the sucrose esters. Results indicate that emulsifier type has a significant effect on the sensory properties of oil-in-water emulsions, and relationships between instrumental and sensory measures suggest that this may be due to the interfacial properties of emulsifiers at the oil–water interface.