Potassium sorbate is used as a preservative in a number of foods, since its anti-microbial properties stop the growth and spread of harmful bacteria and molds. It is used in cheese, baked goods, syrups and jams. It is also used as a preservative for dehydrated foods like jerky and dried fruit, as it does not leave an aftertaste. The use of potassium sorbate increases the shelf life of foods, so many dietary supplements also include it. It is commonly used in wine production because it stops the yeast from continuing to ferment in the bottles.

Food Preservative: Potassium sorbate is used particularly in foods that are stored at room temperature or that are precooked, such as canned fruits and vegetables, canned fish, dried meat, and desserts. It's also commonly used in food that is prone to mold growth, such as dairy products like cheese, yogurt, and ice cream. Many foods that are not fresh rely on potassium sorbate and other preservatives to keep them from spoiling. In general, potassium sorbate in food is very common.
Winemaking: Potassium sorbate is also commonly used in winemaking, to prevent wine from losing its flavor. Without a preservative, the fermentation process in wine would continue and cause the flavor to change. Soft drinks, juices, and sodas also often use potassium sorbate as a preservative.
Beauty Products: While the chemical is common in food, there are many other potassium sorbate uses. Many beauty products are also prone to mold growth and use the preservative to extend the life of skin and haircare products. It is very likely that your shampoo, hair spray, or skin cream contains potassium sorbate.