TANIN VR SUPRA® & TANIN VR COLOR®: The winning team

Tannins in winemaking have 4 points of interest:
• the “sacrificial” effect,
• the anti-oxidant effect,
• the co-pigmentation effect in the presence of colour components,
• the effect of stabilisation in the presence of acetaldehyde.

PRECIPITATION OF PROTEINS OR “SACRIFICIAL” EFFECT Grape proteins combine and precipitate with phenolic compounds. This precipitation reduces the natural amount of grape tannins and can be limited due to the “sacrificial” effect: by using extra tannins that will combine specifically to the proteins. This “sacrificial” effect can be evaluated in the laboratory by measuring the tannins reactivity with a reference protein such as BSA. TANIN VR SUPRA® provides a strong protective effect for natural grape phenolic compounds. Its reactivity is 5 times superior than other vinification tannins.

THE ANTIOXIDANT EFFECT
The use of tannins has always been linked to their ability to moderate the effects of oxygen. They have antioxidant properties and protect the oxidisable compounds. It has been proven that 30 g/hL of TANIN VR SUPRA® added in increments during fermentation reduces the amount of dissolved O₂ three fold in must at the beginning of the fermentation which limits the oxidation risk of easily oxidisable compounds.

THE INHIBITION OF LACCASE ACTIVITY Botrytis on grapes brings with it some laccase and polyphenol oxidase activities that are negative for wine quality. In Botrytis affected musts, the addition of TANIN VR SUPRA® efficiently limits the negative enzymatic oxidase activities.

THE CO-PIGMENTATION EFFECT
Copigmentation comes from the association of coloured pigments with other polyphenolic compounds, usually non-coloured. This association leads to stable co-pigments showing a more intense colour than the single coloured molecules. Red wines that are rich in co-pigments will have a more intense colour at both early and late stages of the vinification. TANIN VR SUPRA® and TANIN VR COLOR® are both tannins with a high co-pigmentation ability.

CONDENSATION EFFECT (STABILISATION OF COLOUR)Acetaldehyde molecules are involved in stabilising simple coloured phenolic structures through reactions leading to more complex molecules. The efficiency of the tannin/anthocyanin bond via an acetaldehyde bridge can be simply demonstrated by saturating a tannin solution with acetaldehyde and then observing the evolution of turbidity over time. A benchmarking study has been done with many tannins available on the market using this method: TANIN VR COLOR® was more than 100 times more reactive than the closest competitor product.

Results of ethanal test with 4 products of the market. TANIN VR COLOR® is the most reactive to acetaldehyde (ethanal), key step in the colour stabilisation and formation of tannin-anthocyanin complexes.

SPECIFIc case: lack of phenolic maturity

When harvest is not at optimal phenolic ripeness, the qualities of TANIN VR SUPRA® and TANIN VR COLOR® are complementary.
Thanks to its remarkable “sacrificial” effect, TANIN VR SUPRA® helps protect the natural extractable grape tannins from precipitating with naturally occurring proteins, while TANIN VR COLOR® brings balance to the tannin/anthocyanin ratio and promotes the production of stable coloured compounds.

TANIN VR SUPRA® is added to the must after the crusher or during the first pump over (if no evidence of Botrytis) (20 – 80 g/hL according to the sanitary state of the harvest). TANIN VR COLOR® is added during the alcoholic fermentation during the colour extraction phase at 10 to 30 g/hL.
Whenever the vintage looks like a difficult one with challenges for grapes with optimal phenolic ripeness, the use of proper tannins, for example, TANIN VR SUPRA® and TANIN VR COLOR® will be a key point to successful vinifications.