The North Carolina-based company has established the managed ecosystem fermentation (MEF) process to take cellulosic, starch or carbohydrate waste and generate chemicals – including proteins and other ingredients that could be used in feed, food or in industrial products – in an economical and sustainable way, the company said.
It has gathered several patents for process, which uses an ecosystem of bacteria, yeast, protozoa and fungi in its fermentation system.
Currently, the company is in the midst of scaling up its recycling system, said Ed Calt, CEO with Integrated BioChem, LLC. The goal of designing the MEF recycling process was to create a way to address waste products.
“The microbial system, when maintained with the proper conditions adapts to what you feed it,” he told FeedNavigator. “There are two different waste streams, one is GRAS [generally recognized as safe] out of a food processing plant that’s classified as safe for entering the food streams – with that we’re going to produce protein that can be used in aquaculture and animal feed.”
“Using sugar beet pulp, you push it through a grinder pump to grind it down to 2mm, mix it with some nutrients, and pump into a fermentation vessel at the right temperature, and then pump it out through sieves to remove what isn’t digestible and then a centrifuge to extract the proteins,” he said. “Then you get interesting.”
What comes “out of the sieves goes to a fertilizer maker as a bio-stimulate – you put it back in the soil and start rebuilding the microbiome of the soil,” he said. “The water that comes out of the centrifuge is still loaded with enzymes because they’re the proteins that are too small for the centrifuge to extract and you put it at the backend of the wastewater plant.”
Additionally, the system can use waste paper, or the by-products generated in paper production to make proteins, said Calt. “One pizza box can contaminate 1 ton of paper [for recycling], but we can take that contaminated paper and process it and convert it into protein,” he added.
“These bugs can be trained to a specific feedstock,” he said. “The other application is the short fibers out of a paper mill – we have proven that the short fibers can be easily converted.”
Although both waste streams – food or paper – have to be prepared in different manners to go through the MEF system, he said. Paper needs to be pulped, while food waste has to be ground.
The system also could be used to generate non-feed grade proteins or products using municipal waste, he said.
The recycling process developed out of an initial interest in finding a way to address hog manure and generate needed compounds like a gasoline alternative or butanol, said Calt. During the development process, the research sifted to look at the chemical processes involved in ruminal digestion.
However, that chemical reaction provided more promise when dealing with organic matter than manure, he said. “That’s how we got into converting garbage into protein,” he added.
The MEF process was designed based on an understanding of how a cow’s rumen works chemically, but without the need to support the rest of the animal, said Calt. “You can change the pH, you can change the temperature, you can add oxygen and create more lipids.”
When a MEF system is established, the microbial system is installed and can be trained to manage several different types of waste streams, he said. The system does not use a single microbe but a combination of several thousand, so it does not have to be maintained in the same type of sterile conditions that a system using a monoculture would.
“Compare it to the way a cow eats – it grabs the grass, swallows it, chews it, digests it and repeats – feed is not sterilized,” he said. However, because the microbial system does not have to support the health of a cow some of the microbes behave differently than they would in a functioning rumen.
Initial testing has been run using the protein generated to feed fish, said Calt. The next step for that exploration will be to run feeding trials with an aquaculture feed producer looking at potentially adding the protein to diets for rainbow trout.
“If the trout farms can use this then it can go into the saltwater marine environment,” he said. “One of the elements right now is comparing it to fishmeal.”
Lab scale and 200-liter production systems have already been tested, but the company is working to establish a larger facility, said Calt.
“We built a pilot plant, and we showed that the process scales from bench to pilot,” he said. “We were running at 200-liters and a full size will be 5,000 liters.”
The initial demonstration facility used waste food from a grocery store, he said.
One potential partner being considered in the scale-up process is a sugar beet facility as the recycling process would provide an alternative profit stream from a waste product, he said.
“It generates several million tons of sugar beet pulp annually – it’s an excellent feed for cattle but it’s 75% water and the cost of dehydrating it is prohibitive,” he added.
Some details of the project remain to be established including the final form the partnership might take, said Calt.
Part of the plan when locating MEF systems in the future will be to set up long-term contracts for low-cost feed ingredients or industrial co-products, he said. “You have to figure out how everyone can make money,” he added.
“We have the raw ingredient they need and we have a known feedstock supply,” he said of the arrangement system. “Part of the strategy is straightforward and simple – we can provide long-term, fixed-price contracts.”