One example of this is in dairy product processing. University of Wisconsin-Madison food science professor John Lucey shared his thoughts on this topic during a panel discussion at the Wisconsin Agricultural Outlook Forum.
“Farms have gotten bigger, but plants have also gotten much bigger the past 20 to 30 years,” Lucey said. “We spend a lot on waste treatment at the farm and the cheese plant.”
The “waste” from a cheese processing plant can come in the form of low-value co-products, such as permeate or acid whey. While some of these products are used to feed animals, Lucey said that is a low-value use for them. On the flip side, products that are land applied can have potentially negative environmental impacts due to the leaching of nutrients into soil, groundwater, or the atmosphere.
Handling these low-value co-products is becoming more challenging for processing plants as environmental regulations get stricter. In addition, the sheer volume of co-products is a lot to deal with. Lucey explained that, when creameries were smaller, they would send the co-products back to the farms where the milk came from to be fed to pigs or other animals. Today, the farms and plants are more spread out, making that option less feasible in many areas.
Drying the co-products and selling them overseas is another opportunity. However, Lucey pointed out that the drying process is expensive, as is shipping them, and this route requires a lot of energy and fossil fuel. “Is that environmentally sustainable?” Lucey asked.
The U.S. currently produces about 120 billion pounds of whey, 600,000 tons of dry permeate, and about 2 million metric tons of acid whey annually. Rather than thinking about these products as a waste stream, Lucey said there is potential to look at them as organic feed stock.
“When you think about crude oil, that goes to a refinery,” Lucey said. “The refinery is breaking it down into different components and each are value-added. A bunch of things come out the other side.”
Would a similar process work for dairy biomass? Lucey and other researchers see the potential there.
“Could these be fermented into a wide range of ‘green’ chemicals?” Lucey proposed. He shared that research is underway to determine if these co-products could be biofermented into biobased chemicals that could be used as precursors for biodegradable bioplastics, among other ideas.
“We take lemons and make lemonade. How do we take problems and turn them into opportunities to create some value-added products, create jobs, and create local opportunities?” Lucey asked. If we can bioferment dairy’s waste streams, from manure to cheese, there’s the potential to create green chemicals and plastics in the future. “We have to wean ourselves off some fossil fuels anyway,” he noted.
