Pizza Hut’s cheese supplier, Leprino Foods, uses the silicone-industrial chemical Polymethylsiloxane in their “Pizza Cheese”. It is not approved by the FDA as a food ingredient; it is intended for use as an anti-foaming agent for boiler water.

In its patented manufacturing process, Leprino Foods sprays “cheese granules” with Polymethylsiloxane, resulting in a concentration of the chemical 90 times higher even than is permitted in boiler water.

The Polymethylsiloxane is used to avoid a normal seven-day aging process for cheese, and allows for a higher food starch content. Without the aging process, cheese can form bubbles during cooking, which blacken and burst. A high starch content also normally causes bubbles. Since Polymethylsiloxane is an anti-foaming agent, it prevents the bubbles from forming.