Sensory relevance of seven aroma compounds involved in unintended but potentially fraudulent aromatization of wine due to aroma carryover.

Bottling regular wines following aromatized wines on the same filling lines bears the risk of unintentional aroma carryover, which has led to accusations of illegal aromatization. Obeying guidelines of good manufacturing practice, aroma carryover with no sensory relevance shall be considered as a technical unavoidable transfer having no legal consequences. To detect sensory relevance, odor activity values greater than one are proposed. Odor detection thresholds (OTs) were determined in water, model wine, and white wine for three lactones, α-ionone, ethyl 2-methylbutanoate, trans-cinnamaldehyde, and eugenol. Using different matrices OTs varied by factors of 2 for α-ionone and up to 23000 for ethyl 2-methylbutanoate. For α-ionone, being most prone for carryover, the three times higher OT of consumers did not trigger any preference for the aromatized wines, but rejection at 300 µg/L. Assessing α-ionone spiked wines by descriptive analysis, significant changes in sensory attributes only occurred at concentrations 10 times above OT.

Uptake and Release of Aroma Compounds by an Ethylene Propylene Diene Monomer Rubber Sealing Polymer: Investigating Aroma Carryover in a Model Wine System.

Aromatized wines and regular table wines are often filled on the same bottling line. Sealing polymers in the filling line absorb volatiles from aromatized wines and may migrate due to insufficient cleaning into the subsequently bottled regular wine. Unintentional carryover of volatiles may lead to accusation of illegal aromatization of wine. Absorption, cleaning efficacy, and migration of volatiles into ethylene propylene diene monomer rubber were investigated in a model system. Direct thermal desorption-gas chromatography-mass spectrometry analysis of seven aroma compounds monitored variation in the polymer (µg/g). Absorption of volatiles was mostly driven by their octanol/water partition coefficients. Cleaning of polymers removed 11 to 62% of the absorbed volatiles. Subsequent immersion of cleaned polymers into model wine revealed migration of 20 to 57% of the remaining volatiles. Sensory tests suggested the impact of transferred volatiles into subsequent model wine. For α-ionone, an odor activity value of 1.03 indicated a potential sensory impact.