From French Fries to Biodiesel
The hospital kitchen at the University Campus is doing more with less -- oil that is.
On a typical day the kitchen serves up some 7,500 meals for patients, staff and visitors, with french fries and onion rings always popular. That takes a lot of cooking oil. Earlier this year, the kitchen switched to a new oil-filtering process that extends the life of the oil, thereby reducing the overall usage by some 35 percent. When the used oil eventually needs to be changed, it’s collected by a company that re-processes it for a range of products from animal feed to biodiesel.
“We used to have to change the oil every four days or so, but with this new filtering process, we can extend the life of the oil to six or seven days,” said Stephan Naleski, executive chef for the clinical food services at the University Campus.
Naleski said that over time small food particles build up in the cooking oil, raising the liquid’s carbon content and making it prone to smoke when heated. Also, the remnant particles can impart unwanted flavors to the food being cooked. The new filtration process uses technology able to screen out food particles 100 times smaller than the old system, thereby extending the oil’s useable life. “We expect this will result in a savings of about 6,000 gallons of oil used a year here,” Naleski said.
When the oil can no longer be used for cooking, it is collected by Baker Commodities, a California-based firm that provides rendering and grease removal services across the country. The oil is transported to the company’s northeast facility in Billerica, Massachusetts, where it is processed for reuse.
Most of the cooking oil is recycled into yellow grease, a product used as a high-energy ingredient in animal feed. Yellow grease is also used to produce biodiesel, a non-toxic biodegradable diesel fuel substitute. According to industry sources, when used in place of petroleum, or in blends with petroleum, biodiesel can reduce carbon dioxide emissions by as much as 78 percent.
“We used to have to pay to dispose of the oil, now we’re getting paid by others to take it and re-process it,” said Alan Levine director of food and nutrition services for UMass Memorial’s University Campus. “It’s a good deal all around, both economically and environmentally.”