Improved sealing polymers and cleaning procedures to mitigate aroma carryover during bottling of aromatised and regular wines on the same filling line

Bottling of aromatised wines and regular table wines often takes place on the same bottling line. Installed sealings in the bottling line absorb volatiles from aromatised wines and, due to inadequate cleaning, carryover occurs into the subsequently bottled regular wine. This unintentional carryover can lead to accusations of illegal flavouring of wine. To minimise the carryover risk, sealing materials that absorb less volatiles are beneficial. Incorporating kaolin and micro-cellulose into the ethylene propylene diene monomer rubber (EPDM) network decreased absorption of the critical α-ionone by 51 and 60 %, respectively.Besides the minimisation of the absorption, a performed cleaning can reduce aroma carryover. So far, knowledge about cleaning parameters that can increase cleaning efficiency is limited since cleaning usually focuses on surficial removal and prevents microbiological cross-contamination. An evaluation of the cleaning parameters, temperature, time and agents clearly revealed a high factor in the considered temperature. The highest cleaning efficiency was seen at 85 °C, whereas the cleaning additives such as citric acid, caustic soda, ozone or dissolved carbon dioxide had no impact. High proportions of the aroma compounds were removed from the polymer in the first 20 min at 85 °C, but none of the performed cleaning sequences was able to remove all compounds.