Problems with off-odor compounds

An off-odor can be caused by a single substance or by a mixture of several substances. Difficulties in describing an off-odor occur particularly in the second case where the smallest change in the mixture composition can lead to a complete palette of odor nuances. 

The individual substances leading to the formation of off-odors can be classified according to different viewpoints source, odor thresholds and chemical structure. The main components from raw materials, contaminants as well as aroma compounds are differentiated by their origin from substances that can be taken up by the packaging from the surrounding atmosphere. 

Off-odor forming residual raw materials can be further subdivided into residual monomers, e.g. styrene, vinyl acetate, acrylic esters, and residual solvents e.g. ethyl acetate. The presence of such residual raw materials can be deduced from knowledge of the chemical composition of the packaging, which allows them to be specifically searched for and quantitatively analyzed. 

Despite these difficulties with the identification of the off-odor sources, most off-odor problems have several typical characteristics in common  

The testing of these off-flavor problems requires a systematic approach where prior 

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