Cream of tartar might be a baking essential that lasts much longer than you would expect. Unless you are a baker enthusiast, it takes a long time to finish a small pack of this white powder.
In such circumstances, one common question arises: Does cream of tartar go bad? How do you know if cream of tartar is still good for baking?
If you are curious about the nitty-gritty of cream tartar, its shelf life, storage methods, how to test if cream of tartar is still active, etc., keep reading. You are about to find out what you’re looking for!
What Is Cream of Tartar?
Contrary to its name, cream of tartar is not cream or dairy products. Cream of tartar (or potassium bitartrate by its scientific name) is actually a byproduct of winemaking. It’s collected from the crystals left behind wine casks.
The crystal is naturally reddish-brown. After a refining process, it gets its white color, hence its name ‘cream’. It is available in powder form and easily found on spices or baking aisle in the supermarket.
So, what does cream of tartar do? For baking purposes, cream tartar works as a stabilizer, anti-caking, and thickening agent.
Meringue recipe typically calls for cream of tartar to help to stabilize the egg whites during whipping to create that high, stiff peaks. It also prevents sugar syrup from crystallizing.
It is also a common acidic component in baking powder to activate baking soda. Hence, it also works as a leavening agent.
How To Store Cream of Tartar
Ideal storage conditions for cream of tartar is similar to other baking essentials, such as baking soda and baking powder. These dry products are sensitive to air and moisture build-up. A cool, dry area, out of heat and moisture is the perfect spot.
That means your pantry, kitchen cupboard, or cabinet works perfectly. Keep it away from the oven, stove, sink, or dishwasher.
To prevent the powder from picking up moisture, always keep it tightly sealed after each use. If the package is not resealable, place leftover powder in a sealed airtight container.
Alternatively, keep it in its original package and store it in a big container together with other dry ingredients. Write a label to indicate when the package is open for the first time.
How To Tell If Cream of Tartar Has Gone Bad
Similar to baking soda or baking powder, cream of tartar also doesn’t spoil or rot as fresh produce does. You just need to keep it away from water or moisture.
Once moisture finds its way into the powder, it can start to lose its potency. If it gets worse, the powder starts to clump or even grow molds (black specks). If that’s the case, it’s time to let it go. Likewise, if the powder turns from white powder to yellowish shade.
Cream of tartar should smell a little acidic. If it smells flat or neutral, it’s likely going bad.
How do you test if cream of tartar is still good for baking?
If you are doubting whether cream of tartar still has its power for baking, take a few minutes to do this quick test. It’s super easy and costs you nothing.
Prepare a half cup of warm water. Drop a half teaspoon of cream of tartar and a pinch of baking soda. If it bubbles or foams, it is still useful for baking.
What can you do with cream of tartar that has lost its potency?
Don’t rush throwing out your cream of tartar. You can use it around the house, mostly for cleaning. Mix it with vinegar to scrub your toilet, sink, or dishwasher. It also works for polishing your stainless steel or metal equipment.
How Long Does Cream of Tartar Last?
Cream of tartar is a durable item. Its shelf life is usually indicated by a “best by” or “best before” date before purchase. Of course, it may stay good after its recommended date, depending on your storage.
In case, the pack you buy doesn’t carry a “best-by” date, the average shelf life of cream of tartar is four years after its production date. Keep it away from water and moisture to maintain the shelf life.
Classification | Pantry |
---|---|
Cream of tartar (unopened or opened) | 4 years |
This table is a rough estimate. The actual shelf life largely depends on storage conditions. Spare a few minutes for a quick test to ensure if it is still potent.
FAQs
Cream of tartar is generally safe to use after its expiration date. But you may need to check if it’s still effective for your baking recipe.
Do the quick test by dropping a half teaspoon of cream of tartar and a pinch of baking soda into a half cup of warm water. If it foams, it should work well for baking. If not, open a new pack rather than risking your baked goods.
Alum (or sodium aluminum sulfate) is not cream of tartar. Both of them are indeed common components in baking powder.
Don’t let missing ingredients ruin your baking routines. If this time you’re out of cream tartar, you have a handful of choices to find from your kitchen, from vinegar, lemon juice, buttermilk, yogurt, etc.
Final Thoughts
Cream of tartar is a baking essential that keeps well. But, without proper storage, it can lose its potency and eventually go bad.
Keep it in a cool, dry area, away from heat and moisture. It retains its freshness and potency for at least four years. If you’re in doubt, give it a quick test to see if it’s still effective for baking. Discard the powder if you spot spoilage symptoms, such as lumpy powder, discoloration, black spots, and molds.
Also check our article for a comprehensive guide to choose the best substitutes for cream of tartar.

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