The vast scale of food waste has recently captured the spotlight because it is a massive driver of global warming. Between 30% and 40% of food produced in the world ends up in a landfill where bacteria consume it, creating methane, a potent greenhouse gas. The amount of methane produced annually by food waste surpasses the emissions of every nation other than China and the U.S.
Bio-dehydrators — machines that mechanically accelerate the decomposition of food waste — have the potential to significantly reduce the amount of methane produced in landfills. These machines, placed in restaurants, cafeterias, and grocery stores, can reduce food waste volume and weight by 80% to 90%. The dehydrated material takes up less space, so it’s easier to store and less expensive to transport. It makes it desirable for composters and methane producers — or even for use in products like pet food.
Dried food scraps contain significant levels of nutrients that can benefit the soil. It can also serve as a sterile substrate that can be inoculated with beneficial microbes to produce specialized soil supplements or to make a compost tea for use in a garden or landscape.
Wet Waste Spoils, Dry Waste Can Feed the Soil
Reducing the volume and weight of food waste decreases the workload and environmental impact for everyone involved in its post-use processing life cycle.
For example, it’s easier for food service and grocery store employees to collect and store dry material than wet material. And by processing the waste, they avoid creating more methane in the landfill if they throw it out.
The dried food waste can be stored conveniently, without offensive orders, to offset the need for frequent pickups, lowering the tipping fees paid by restaurants and grocers. And waste haulers can make fewer trips, so they use less gas.
Many composting facilities have an oversupply of compost, which can drive down its resale value. Dried food waste can be stored almost indefinitely, giving composters time to make the best compost possible. It also allows composters to explore other high-value options for the material.
The U.S. is experiencing a fertilizer shortage during the conflict between Russia and Ukraine. We get much of our fertilizer and its precursors from that area. Bio-dehydrated food waste has high levels of nitrogen, phosphorus, and potassium, the macro-nutrients important to healthy plants and other organic matter essential for healthy soil.
63.1 million tons of food waste was generated in the commercial, institutional, and residential sectors in 2018, 21.6 percent of total MSW (municipal solid waste) generation.” Source: U.S. Environmental Protection Agency
People Can Influence Business Food Waste
According to the National Conference of State Legislatures, 39% of the food wasted in the U.S. is lost at business locations, while households account for 43%. Each of us can make a difference at home and by asking restaurants and other food-related businesses to make changes that reduce waste. A great way to start is by asking the food-service businesses you visit how they handle leftover food.
If even a third of the waste we currently produce were dried and reused, it would significantly affect global warming. A 2020 study published in the journal Earth System Science Data, The Global Methane Budget 2000-2017, suggests that we must align public policy and business practices and take immediate action to reduce methane emissions.
Food waste dehydration is easy to implement and immediately yields a valuable store of nutrients and organic matter. Composting is also great, but it requires four to six months to produce usable materials, which makes processing large quantities of food waste inefficient. By contrast, the bio-dehydration process takes from 9 to 24 hours, depending on the size of the batch.
Drying Food Waste Transforms It into Food Worth
Because most food waste goes to landfills, the potential for improvement in the food service industry is immense. A few commercial food waste generators use on-site aerobic digesters, but these often treat the food waste and pump the effluent into the wastewater system, treating it like sewage. Much of the rest is incinerated to generate electricity. But we need to keep those nutrients in the nutrient cycle – get them back into the soil. An ecosystem is only as robust as its soil, and we’ve seen that play out many times throughout history.
Drying makes managing the material much more manageable. Food is the heaviest thing that goes into a commercial kitchen trash can. Suppose you produce 1,000 pounds of food waste per week — 52,000 pounds annually. By dehydrating it, that food waste is reduced to around 10,400 pounds, based on a conservative estimate of 80% weight reduction. A 30-gallon barrel could hold what would have been 1,000 pounds of wet food waste requiring many dumpsters.
I founded Hungry Giant, a bio-dehydrator and bio-digester manufacturer, to focus on pre- and post-use food waste in the institutional and commercial sectors. We make bio-dehydrators for hospitals, nursing homes, military installations, supermarkets, restaurants, office buildings, sports venues, prisons, colleges and universities, and K-12 schools. All these organizations can help decrease the volume of wasted food by sending usable goods to food banks. When they cannot reuse food before it spoils, we hope they’ll consider drying it instead of dumping it.
Food waste has been out of sight and out of mind for so long that we have had to reteach awareness, but real progress is starting. Changing our perception of food waste and seeing its value is critical. Understanding its life cycle would be a huge step in solving the problem. Food waste isn’t sexy, but it is extremely important to the health of our land. We have the resources to improve our priorities around food waste. It is time to view it as a valuable resource, not a waste.
About the Author
Chris O’Brien is the founder and CEO of Hungry Giant Waste Systems, which distributes bio-grinders and bio-dehydrators. He previously founded the Australian company that manufactures Hungry Giant equipment.