What is the key difference between approved preservatives and processing aids noted by consumer analysis?

Answer

A processing aid might be used in large quantities during manufacturing but must be nearly absent in the final product.

Processing aids are substances used during manufacturing that must be nearly absent in the final product, whereas direct additives are intentionally present in the finished food.

What is the key difference between approved preservatives and processing aids noted by consumer analysis?
foodSafetyconsumptionpreservativeadditive