Cream of tartar is found in the grocery store's baking aisle and is used primarily in baked goods.
If you’ve ever looked at the ingredient list for meringues or angel food cake and wondered what cream of tartar is, you’re not alone.
If you’re new to baking, cream of tartar will become your best friend and lessen the learning curve quite a bit.
Below, we explain what cream of tartar is, its uses, and how to preserve it.
What is Cream of Tartar?

Cream of tartar is a white powder that stabilizes egg whites in meringues and cakes and gives snickerdoodles a unique flavor.
It comes from tartaric acid, a byproduct of the wine-making process.
When grape juice ferments, it releases potassium bitartrate that forms crystals that stick to the cask's sides.
These crystals are collected from the sides of the barrel and processed into cream of tartar.
Cream of tartar has a tangy flavor but is not used in large enough quantities to affect the food's flavor.
I have used it often and have never noticed a tart flavor where I didn’t want it.
How Long Does Cream of Tartar Last?
Cream of tartar is sold like spices and should be stored similarly.
As long as it's kept in an airtight container and kept in a cool, dry place, it will last indefinitely.
The manufacturer recommends four years, but this is the peak quality time, not a safety date.
How Do You Know When Cream of Tartar Is Still Good?

You test the potency of cream of tartar the same way you would test the strength of baking powder.
Take half a cup of water and stir in half a teaspoon of cream of tartar with a pinch of baking soda.
If foam doesn’t form, the cream of tartar has gone bad.
What Does Cream of Tartar Do?

A pinch of cream of tartar stabilizes egg whites during the whipping stage by strengthening the delicate air pockets of the egg whites so they don’t break.
This is frequently used for meringues, made into cookies, or used for lighter-than-air cakes like angel food cake.
8 Best Corn Syrups As Substitutes will give you some ideas on other baking substitutes.
The Best Way to Store Cream of Tartar
If you bought cream of tartar in a screw-top jar, storing it in this jar is okay.
If you purchased it in a bulk bin, transfer it from the bag to a screw-top jar and store it away from the stove, in a cool, dry place.
A dark pantry or spice rack is an ideal place to store cream of tartar because it's safe from moisture and excessive heat.
Make sure you seal the container completely after each use before storing it.
Can You Use Cream of Tartar After Its Expiration Date?

Yes, you can use cream of tartar after its expiration date, but it won’t be effective if it fails the test described above.
Generally, it will last six months after the expiration date if it doesn't come in contact with moisture.
Conclusion
Cream of tartar is a secret weapon of bakers but is little known outside of this circle of cooks.
Knowing how to use it properly will increase your baking level in no time by helping you to bake beautiful meringues and cookies.
Jason