Paul Gambino and other members of the Gambino family were also heavily involved in the mozzarella cheese and pizza business. This included factories, distribution and pizza parlors. Before he died, Gambino apparently intended to buy a big dairy farm in South America.

That was from Vicious Circles by Jonathan Kwitny, which investigates how the mob had infiltrated legitimate industries. There is also this:
"Paul Gambino (Carlo's brother) and Frank Ferro briefly took over the business of sharpening knives for retail meat sellers. Their operation, though, amounted to little more than a shakedown of the knife grinders who had previously handled the work. After a brief time in business, the racketeers offered to quit if the knife grinders' organization would pay them $300,000. The organization paid, and the chain stores sent their knives back to the original grinders"