Cream of tartar derives from the substance potassium bicarbonate, which is a type of salt. Potassium bicarbonate is the byproduct of tartaric acid, a substance produced through the process of making wine. This element goes by several other names, including potassium hydrogen tartrate, and monopotassium tartrate.
Cream of tartar forms its common culinary texture of a fine white powder through a fermentation and crystallization process. This substance hardens and forms solid particles upon creation. Cream of tartar might collect inside wine bottles as wine ages, and also grows inside grape juice containers. Occasionally, it appears inside old containers of grape jelly, too. Once created, cream of tartar does not dissolve into the surrounding substance, making it easy to collect and use. Upon gathering the fermented crystals of potassium bicarbonate, professionals put the substance through a treatment process that involves refining, coloring and packaging the product. It then appears on grocery shelves as cream of tartar. Although shelf stable, cream of tartar does need to be kept away from humidity, as exposure to moisture makes it develop clumps. Cream of tartar sees uses mainly as a stabilizer in whipped cream and egg whites and adds volume to pastes and gels. It helps thicken substances, too, and retains the color of certain foods.