E81 is a designation for a specific type of food additive known as sodium benzoate. It is commonly used as a preservative in various food products to prevent spoilage and extend shelf life. E81 helps inhibit the growth of bacteria, yeast, and molds, making it a popular choice in the food industry. In addition to its use in food, E81 can also be found in some personal care products and cosmetics. It is important to note that while E81 is generally recognized as safe when used in regulated amounts, some individuals may have sensitivities or allergies to it.