Analysis of neutral volatiles of mayonnaise by direct gas chromatography and mass spectrometry

Abstract

AbstractSimple procedures have been developed for analyzing neutral volatiles from mayonnaise by direct gas chromatography and combined direct gas chromatography‐mass spectrometry. For gas Chromatographic analysis, a glass liner containing glass wool coated with alkali in the lower quarter and plain glass wool in the remaining space is placed in the heated inlet of a gas Chromatograph, and mayonnaise and water are injected onto the plain packing. Neutral volatiles eluted from the mayonnaise by the combined action of water, carrier gas, and heat collect on the cool column of the gas Chromatograph, but acetic acid is trapped by the alkaline glass wool and thus does not interfere with the analysis. After removal of the liner with the spent sample, the temperature of the column oven is programmed to resolve the volatiles. For mass spectrometric analysis, neutral volatiles are passed directly from a Chromatograph inlet to a second inlet liner containing a porous polymer that traps most organic compounds but has low affinity for water. These neutral organic volatiles are desorbed from the porous polymer in the inlet of a Chromatograph interfaced with a mass spectrometer for analysis. This procedure allows components resolved by the gas Chromatograph to be identified by mass spectrometry without interference from either water or acetic acid. A total of 21 neutral volatile compounds was identified in mayonnaise.