Effect of emulsion characteristics on the release of aroma as detected by sensory evaluation, static headspace gas chromatography, and electronic nose.

The effects of emulsion structure and composition of the matrix on the release of linalool (nonpolar) and diacetyl (polar) were studied using sensory evaluation, static headspace gas chromatography, and an electronic nose. The matrices used were water, rapeseed oil, and eight oil-in-water emulsions differing in oil volume fraction (0.05/0.5), emulsifier type (sucrose stearate/modified potato starch), and homogenization pressure (100/300 bar). Fat content strongly affected the release of linalool, but it was not as critical a factor in the release of the more polar compound, diacetyl. A slight effect of the emulsifier type on the release of aromas was observed with sensory and gas chromatographic methods. The reduced droplet size, resulting from higher homogenization pressure, enhanced the release of linalool but had no effect on diacetyl. Sensory and gas chromatographic methods detected aroma changes quite similarly. The electronic nose was capable of detecting only the effect of fat on linalool.