Term for the "atypical ageing tone" or "atypical ageing note" in wine, emphasising the distinction from the "true ageing tone". There are very many synonyms such as acacia, floor wax tone, hybrid tone, candle wax, Mediterranean note, furniture polish, naphtalone, wet cardboard (papier mâché), wet cloth, dirty cloth, mothball tone, moth powder tone, soap tone (soapy), nitrogen builder, dull, detergent tone and washing powder tone. Aminoacetophenone (AAP) was identified as the responsible aroma component in 1993. The plant hormone indoleacetic acid is likely to have a high proportion as the starting substance. It is a natural wine substance that only causes negative sensory changes at higher concentrations. The perception threshold is 0.5 µg/l (microgram = millionth of a gram), values between 0.5 and 1.5 µg/l are considered mild UTA. In aqueous solution, the substance causes a floral aroma of acacia and oranges; only when combined with other aroma substances does the typical UTA tone develop. Together with other substances, AAP is the cause of the foxy of certain American vines, especially the species Vitis labrusca. This is why UTA wines often have this typical "fox taste".
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freier Autor und Weinberater (Fine, Vinum u.a.), Bad Krozingen