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Dealing with fruit from water-stressed vines is always challenging for winemakers. There are many difficulties that can occur - grapes can accumulate sugar due to dehydration but may be far from ripe: uneven ripening (sweet and sour); unbalanced pH and acidity; atypical ageing (oxidation); reduced concentration of aromatic precursors; concentrated sugar (over-ripe/jammy); microbial spoilage; higher solids affecting settling, poor colour extraction…


With drought and high temperatures, vines shutdown photosynthesis. Consequently, grapes do not reach aromatic maturity, resulting in LACK OF AROMA and even GREEN CHARACTERS in wine. Red grapes may not reach full phenolic maturity, resulting in a LACK OF COLOUR and give of UNPLEASANT TANNINS.
With the shutdown of photosynthesis, grapes begin to dehydrate and sugars concentrate. The accumulation of sugar (with potential glucose/fructose imbalances) and additional low levels of nitrogen compounds make FERMENTATION DIFFICULT. These higher sugars can lead to jammy/cooked berry characters.
As a self-defence and to regulate dehydration, grapes skins become thicker thus affecting PHENOLIC EXTRACTION and PRESS YIELD. The high ratio skin/liquid produces a must generally higher in potassium, hydroxycinnamic acids and catechins that result in wines with HIGH pH and greater sensitivity to OXIDATION and MICROBIAL SPOILAGE. The higher skin content of smaller berries may also result in higher solids content and be difficult to settle.
Finally, heat and sun exposure promote the degradation of malic acid affecting ACID BALANCE.


Low yield / Difficult extraction
Use maceration enzyme to improve polyphenol extraction, increase the yield in juice/wine and improve settling. Increase the usual dosage of enzyme to 30 g/ton of Enartis Zym Color Plus at crusher for reds, 30 g/ton of Enartis Zym Arom MP in the press or during maceration for whites and rosés.

High pH, risk of oxidation and microbial contamination
In white vinification, reduce the content of oxidisable catechins by fining with 5-15 g/hL of Plantis AF. Use a wide spectrum antimicrobial such as Enatis Stab Micro M to limit the
development of spoilage microbes and improve fermentations:
- white vinification: 5-10 g/hL during settling or after flotation;
-red vinification: 50-100 g/ton at crusher.

Difficult fermentation condition
Use a dominant yeast strain, fructophilic and resistant to high alcohol.

High sugar musts stimulate yeast growth and requires complete nutrient additions with both available nitrogen and survival factors. It is essential measure yeast available nitrogen and adjust where necessary.
1) Nutriferm Energy used at inoculation provides essential nutrients for optimal yeast development.
2) Nutriferm Arom Plus used at inoculation not only contributes to yeast growth but also fruity aroma production.
3) Nutriferm Special used after 1/3 sugar depletion to assist yeast with resistance to stress, improves fermentation kinetics and reduces production of H2S.
4) Nutriferm No Stop after 1/2 fermentation is complete, improves yeast cell membrane fluidity, yeast fermentation activity and resistance to stress and ensures reliable fermentations.

Green Character
Minimize green character expression with oak alternatives Incanto and Incanto N.C. range or by using fermentation tannins like Enartis Tan Citrus and Enartis Tan Red Fruit.

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