Multidimensional Gas Chromatography-Olfactometry Based Investigations of Odor Quality Issues in Packaging and Consumer Products, 2004 PLACE Conference

Application: Many important factors such as packaging appearance, product presentation, and sensory impact influence the commercial success of packaged consumer products. Consumer perception of aroma quality is very much context driven.

Executive Summary: A "flora"’ aroma character perceived as wonderful in a garden or fragrance environment is an unacceptable taint in bottled drinking water. Alternately, the unpleasant odor of butyric acid perceived as a major malodor contributor in high-density livestock environments is a primary aroma and flavor contributor to Parmesan cheese. Unfortunately, malodor characterization is a very demanding analytical challenge. This is due to the fact that aroma or odor critical components are typically present at very trace levels in a complex matrix of odor insignificant volatiles.

The typical response to crisis-driven malodor issues is to extract or concentrate from headspace the volatile compounds, separate them by GC, identify them by MS, and speculate which of many compounds might cause the odor. Experience has shown that a much more effective approach to these investigations is GC-olfactometry based. With GC-O technologies, odor profile ranking studies are carried out relative to the in-situ headspace volatiles collections taken directly from the product under investigation. This GC-olfactometry approach begins with the development of a detailed odorant ranking profile for a sensory graded "worst" case sample. Equivalent comparative odorant ranking profile analyses for equivalent sensory graded "best" case samples will indicate which "potential" odorants account for the odor quality defect.

The applications presented in this paper illustrate that an integrated MDGC-MS-Olfactometry system can be a powerful tool for maximizing the efficiency of odor and aroma investigations. Illustrated odor quality degradation processes can include odorant cross-contamination between packaging and product, critical aroma volatile loss through scalping by packaging wall surfaces, and oxidation based odor quality degradation. As the application series shows, oxidation based odor quality degradation can occur through more indirect and complex processes compared with the more commonly expected through-wall oxygen transmission. When considering aroma/odor/ flavor quality of any packaged product, package selection is essential in relation to the aroma character defining components associated with the particular product being packaged. This is also true for bottled drinking water where the defining character is no odor. Any odor deviation from this absence of odor character—whether good or bad—is an odor quality taint.