Tannic Acid (Food Grade)

Tannic acid is a purified, food-grade tannin used to add structure, grip and ageing potential to homemade wine. If a wine tastes thin, flat or soft in the mouth, a small dose of tannin is usually the missing piece. It works in reds, whites and fruit wines, and this fine powder dissolves easily and comes in 25g, 100g, 500g and 1kg packs.

Best suited to

• Red wines that taste thin, soft, or lack grip
• Fruit and country wines with little natural tannin of their own
• White and rose wines that need a touch more body (small doses only)
• Kit wines where you want more structure than the kit delivers
• Wines you plan to age, where tannin helps them develop and hold

Technical specs

• Form: Fine, water-soluble powder
• Grade: Food grade, plant-derived tannin
• Source: A blend of natural tannin extracts, no fillers
• Typical dose (reds): About 0.1 to 0.3g per litre, added before fermentation or during ageing
• Typical dose (whites and rose): Much less, around 0.05g per litre, or none at all
• Available sizes: 25g, 100g, 500g, 1kg
• Storage: Cool, dry, sealed. Keeps for years if kept dry
• Also used for: Rust conversion on metal (same chemistry)

Which size do I need?

• 25g - a batch or two, or bench trials to dial in your dose.
• 100g - a full season of winemaking without reordering.
• 500g - best value per gram for regular winemakers.
• 1kg - bulk, for high-volume or group winemaking.

When to choose tannic acid over grape tannin

Tannic acid is a purified tannin, so it is not identical to the grape tannin your reds pull from skins and seeds during fermentation. But it does the same job when you need to adjust a wine that is short on structure. Reach for it when a red is fermenting or ageing thin, or when a fruit or country wine has no tannin of its own to build on. If your grapes had good skin contact, you may not need any.

Keep it separate in your head from acid adjusters like tartaric or citric acid. Tannin changes mouthfeel, body and grip, not pH or sourness, so they do different jobs and are often used together in the same wine.

Practical notes

Dissolve tannic acid in a little warm water or wine first so it disperses evenly through the batch. For reds, add it before or during fermentation for structure, or a smaller dose at finishing to firm up the mouthfeel. Whites and rose need very little or none, since too much makes them harsh and drying.

The safest way to dose is a bench trial: split off a few small samples, add tannin at different rates, taste them side by side, then scale up the one you like to the full batch. It is easy to overdo, and an over-tannic wine tastes bitter, so start low. You can always add more, but you cannot take it back out.

Rust conversion: tannic acid also reacts with iron oxide to convert rust into a stable compound, which makes it handy for prepping metal before painting or sealing. This is supplied for winemaking, but the same chemistry applies.

Reviewed by the AHB Brewing Team - July 2026