Tropical fruit aroma in white wines: the role of fermentation esters and volatile thiols

Tropical fruit aromas in wines are thought to be important to wine consumers, although there is little research to confirm this statement. With so many wine styles available, it has become important to understand the qualities that are desirable to consumers and how to achieve those qualities. Thiols and esters are compounds that have been found to cause tropical fruit aromas in chardonnay (ref). Fermentation temperature gradients and skin contact were found to increase these compounds using micro scale fermentations. This work aimed to scale up these fermentations/operations to determine if the desired tropical fruit aromas could still be achieved and if there is a perceivable difference in tropical fruit aromas, liking, and emotional response in the wines at the consumer level.

It is fundamental for wineries to know the potential yield of their vineyards as soon as possible for future planning of winery logistics. As such, non-invasive image-based methods are being investigated for early yield prediction. Many of these techniques have limitations that make it difficult to implement for practical use commercially. The aim of this study was to assess whether yield can be estimated using images taken in-field with a smartphone at different phenological stages.

Regenerative agriculture (RA) practices aim to minimize soil disturbance, keep soil covered, maintain living roots underground, and integrate livestock to improve soil health and sustainability.

Solo attraverso un adeguato intervento di estirpazione e reimpianto dei vigneti è possibile preservare, adeguare e valorizzare il patrimonio viticolo e le produzioni che da esso derivano.
Il reimpianto dei vigneti è pertanto da intendersi come una normale pratica agricola, alla pari della rimonta di stalla in campo zootecnico, ma può assumere toni problematici quando, come si verifica adesso in Toscana per una serie di circostanze legate alla profonda trasfor­mazione della viticoltura avvenuta negli ultimi 30 anni, troppi impianti giungono contem­poraneamente a fine ciclo produttivo e devono essere rinnovati.

The use of glutathione (GSH) in winemaking has been legitimated recently, according to OIV resolutions OENO 445-2015 and OENO 446-2015 a maximum dose of 20 mg/L is now allowed to use in must and wine. Several studies have proven the benefits of GSH, predominantly in Sauvignon blanc. Thus, oxidative coloration of must and wine is limited, aroma compounds such as volatile thiols are preserved, and the development of ageing flavors such as sotolon and 2-aminoacetophenone is impeded. The protective effect may be explained by the high affinity of GSH to bind o-quinones which are formed during phenolic oxidation and which are known to initiate browning and other oxidative changes. Some researchers have proposed the hydroxycinnamic acid to GSH ratio (HGR) as an indicator of oxidation susceptibility of must and could show that lower ratios yielded lighter musts.