Stability of Volatile Compounds Recovered During the Winemaking Process

• Published in: Chemical engineering transactions 2019-06, Vol.75
• Main Authors: Lorenzo Guerrini, Piernicola Masella, Giulia Angeloni, Fabio Baldi, Luca Calamai, Alessandro Parenti
• Format: Article
• Language: English
• ISSN: 2283-9216
• DOI: 10.3303/CET1975009

The alcoholic fermentation has a marked impact on wine aroma. During this phase, several compounds are produced by yeasts, and they overall constitute the so called “wine secondary aroma”. However, several of these compounds, mainly the esters responsible for the fruity flavour, are lost during the process. The preservation of beverage aroma and the loss recovery during processing is a key issue that is becoming extremely important in the winemaking technology. Thus, in a previous experiment, the aroma fermentation losses were recovered and added back to the wine. The effect of this practice was measured with chemical analysis, and the flavour difference was perceived at a panel test. Hence, a device was developed to recover these compounds by condensation was developed and patented. The condensation device avoids the escape of aroma compounds from the grape juice during the fermentation. Immediately after the production, the wines made were different from the control wines. However, there is a lack of information about the stability of the recovered compounds during the wine aging. Hence, this study evaluates the aroma of 3 wines produced with the condensation technology during 1 year of storage. In this trial, three fermentations on different grapes (cv. Sangiovese, Merlot, and Cabernet Sauvignon) were conducted with and without the condensation device. The fermentations were conducted at industrial scale. The produced wines were analysed immediately after the production, and during 1 year of storage. The differences were assessed chromatographically (HS-SPME-GC-MS) and with dedicated discriminant sensory test (i.e. a triangular test). Immediately after the fermentation, in the condensed wines significantly higher concentrations of esters were found. The interested compounds are considered positive in wines and responsible for the fruity flavour. Furthermore, alcohols increased as well as the hexanoic acid. The differences were perceived at the sensory test immediately after the wines production. During the storage all the differences in chemical composition was maintained. Furthermore, after 1 year, the differences were perceived at the sensory test.