Acetic acid is what gives vinegar its pungent smell and sour taste, and has been used in homes for more than 10,000 years. In our products, it is used as a cleaning agent that removes dirt and soils, and also as a pH adjuster that alters the pH of a product to improve stability. Every formula has an optimum pH to make it work best. For example, a formula that is more acidic works better for soap scum removal. Its opposite, a formula that is more alkaline, might be more effective at removing grease or greasy soils. We use pH adjusters to make sure we achieve the best pH for a particular job. Also, the pH of a formula can affect how long it lasts within a container – for example limiting its tendency to corrode a tin, container or dispenser.