Tartaric Acid (Food Grade)

Tartaric acid is the main acid found in grapes, and the standard choice for adjusting the acidity and pH of homemade wine. This is a food grade powder, available in 25g, 100g and 500g packs. If a wine tastes flat or your pH is reading too high, this is what brings it back into balance.

Best suited to

• Grape wines that taste flat, soft, or lack freshness
• Lowering pH before fermentation to protect the must and help fermentation run clean
• Country and fruit wines that need their acidity lifted
• Kit wine corrections where the supplied acid was not quite enough

Technical specs

• Form: Fine white powder, fully soluble
• Grade: Food grade
• Source: Derived from grapes (the natural wine acid)
• Additive code: E334, approved in Australia and New Zealand
• Available sizes: 25g, 100g, 500g
• Typical dose: About 1g per litre lowers pH by roughly 0.1
• Storage: Cool, dry, sealed. Keeps indefinitely if kept dry

Which size do I need?

• 25g - trial size for a single small batch or a quick kit wine correction.
• 100g - enough on hand for a few corrections without committing to bulk.
• 500g - best value per gram, enough for many batches.

When to choose this over malic or citric acid

For grape wine, reach for tartaric first. It is the acid grapes already contain, it is stable, it does not get eaten by bacteria during fermentation, and it gives wine its proper vinous bite. When you are not sure which acid a grape wine needs, tartaric is the safe answer.

Choose malic acid instead when you are making cider, or a fruit wine that you want to taste crisp and green-apple fresh. Just don't add malic to anything going through malolactic fermentation, because the bacteria will convert it to lactic acid and undo the work.

Leave citric acid for after fermentation is fully finished. It brings a sharp lemony note, but if bacteria get at it they can throw off buttery and vinegary off-flavours. Tartaric has none of that risk.

Practical notes

How much to add: Roughly 1g per litre will drop pH by about 0.1. So to take a 20L batch from pH 3.6 down to 3.4, you are looking at around 40g. Always measure with a meter or test kit rather than guessing, and adjust in small steps.

How to add it: Dissolve the powder in a small amount of warm wine or water first, then stir that solution through the batch. Adding it before fermentation lets it integrate properly.

A note on cold weather: If you cold stabilise or store wine through a Melbourne winter, some added tartaric will drop out as crystals (tartrate) and your acidity will ease back a touch. Account for that if you are adding right up to your target.

Storage: Keep it dry and sealed. Tartaric acid is happy on the shelf for years as long as moisture stays out.

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