With the high temperatures of the past week, many vines shut down photosynthesis, the grapes dehydrated and got concentrated, skins became thicker and winemaking challenges appear. We are observing different sugar/acid/phenolic/aromatic maturities with high Brix, high fructose content, lower phenolic content and lower yield. As winemakers, we need to adapt our winemaking practices to grapes composition. Here are some winemaking technics and tools we recommend to optimize wine’s quality.
Optimize Extraction of Skin Compounds and Juice Yield using Extraction Enzymes.
To improve extraction of skin compounds, and increase juice yield, we recommend using purified maceration enzymes, such as Oenozym Crush Red. Its application on grapes results in wines with higher color intensity, especially red pigments, higher concentration in skin tannins, more RGII polysaccharides, interesting for their stabilization and mouthfeel properties, an improved filterability due to the reduction of PRAG and increase in free run juice/wine yield
Adjust initial Brix.
The addition of water to adjust the initial Brix is a great way to manage alcohol content and reduce the risk of stuck fermentation. 2 ways can be done: replacement of must by water or simply addition of water. HERE is a link to help you calculate water additions. Adding water will help reducing initial Brix but will also dilute yeast nutrients, total acidity, and phenolic compounds. For that reason, it is important to check and adjust your acidity and pH, and your YAN to a proper level after you added the water. We also recommend adding 5-10 g/hL of Vinitan Advance (grape tannin) to the water to compensate the dilution factor on skin tannins.
Prevent stuck fermentation by using a fructophilic yeast.
To ensure completion of fermentation, especially in high Brix and high fructose conditions, we propose a “no restart” protocol that consists in using a second inoculation with a fructophilic yeast such as L.A. Bayanus at 8-5°Brix, rehydrated with OenoStim to improve yeast health, resistance to stressful conditions and optimize their metabolism.
Protocol: At 8-5°Brix to your fermenting wine, you can add L.A Bayanus to ensure fermentation completion and avoid a full restart protocol.
Rehydrate 40g/hL of L.A Bayanus with 40 g/hL with OenoStim.
Acclimate to wine by adding same volume of wine and wait 30 min.
Repeat acclimation step 2 times.
Add to fermenting tank and mix gently.
Prevent ‘overripe’ aromas by boosting fresh fruit expression
OptiEsters, is a yeast nutrient, composed of amino acids, sterols and ergosterols selected to increase the production of esters, acetates and ethylesters, thus increasing red fruits, floral, berries notes. It increases aromatic complexity and reduces the perception of overripe or green characters.
Stabilize phenolics and balance mouthfeel
Natur’Soft is a specific preparation of yeast hulls, selected for their high content of mannoproteins. Natur’Soft increases wine complexity, reduces tannins aggressivity perception, stabilizes color, and enhances fresh fruity notes.