Polyester cotton is the most common fabric used to make dust coats, although Hard Yakka is a manufacturer of a 100% cotton dust coat, the Y06040. Overalls are made from all cotton, and although the Hard Yakka dust coat is made from a lighter weight material, it is often used in similar environments.
The addition of polyester increases suitable for working with liquids, since polyester repels water. For this reason, food industry dust coats are often manufactured using this fabric.
Another feature of food industry garments is that they are designed to minimise places where food could get caught up and hence be more hygienic. Most food industry garments place pockets on the inside for this reason.