Food waste includes uneaten portions of meals and trimmings from food preparation activities in kitchens, restaurants and cafeterias. It is the third largest component of generated waste by weight. Because of its low composting rate, it is the largest component of discarded waste by weight.

According to a study by the University of Arizona Garbage Project, each of us throws away 1.3 pounds of food every day or 474.5 pounds per year, considerably more than EPA's data showed. The U.S. Department of Agriculture also shows a higher amount of food waste than EPA. The USDA estimates that higher percentages of fresh fruits and vegetables, dairy and grain products are thrown away, while lower percentages of meat, dried beans and nuts, and processed foods are discarded.

Most food waste is landfilled or managed via in-sink food disposers. Food waste composting is in its infancy, held back by cost and vector control concerns. However, large scale projects in San Francisco, Seattle and Toronto may show how to compost food waste effectively.

Increased consumption of packaged foods and the use of food waste disposers were key factors causing food waste's share of the solid waste stream to decrease by fourteen percent from 1960 to 2005.

Chaz Miller is state programs director for the National Solid Wastes Management Association, Washington, D.C. E-mail the author at: cmiller@envasns.org.

Sources:

Biocycle Magazine, www.jgpress.com

Composting Council of Canada, www.compost.org

Cornell Waste Management Institute, www.cwmi.css.cornell.edu

“Municipal Solid Waste in the United States: 2005 Facts and Figures,” Office of Solid Waste, Washington, www.epa.gov/osw

“Measurement Standards and Reporting Guidelines,” National Recycling Coalition, www.nrc-recycle.org

U.S. Composting Council, www.compostingcouncil.org

*2005 EPA estimates.

Food Waste Municipal Solid Waste (MSW) Facts:

Generated:

  • 29.2 million tons or 11.9% by weight.*

  • 197 pounds per person per year.*

  • Food waste is 70% water, 30% solids.

Composted:

  • 690,000 tons, a 2.4% recovery rate.*

  • Organic and highly compostable.

  • Grocery store food processing trimmings are a prime resource for composting facilities.

  • 31 cities and counties collect food waste for composting.

  • Most programs are in California and Washington.

The Composting Process:

  • Composting is the controlled decomposition of organic matter by microorganisms into a humus-like product. The heat and energy generated destroys weeds and human pathogens.

  • Backyard compost piles that include food wastes must be tightly controlled to eliminate pests.

Composting Cost:

  • Tipping fees usually are charged for incoming food waste.

Incinerated or Landfilled:

  • 28.5 million tons or 17.1% of discarded MSW by weight.*

  • Usually the wettest component of MSW with a moisture content of 70% and BTU value one-third that of MSW.

Landfill Volume:

  • 21.4 million cubic yards or 5.3% of landfilled MSW in 1997.

  • Food waste can decompose into methane in a landfill.

Density:

  • Landfilled food waste weighs 2000 pounds per cubic yard.

  • Food scraps, solid and liquid fats weigh 412 pounds in a 55-gallon drum.

Source Reduction:

  • Packaged foods create less food waste.

  • In-sink kitchen disposer units transfer disposal of food waste to the wastewater system.

End-Market Specifications:

  • Each facility has its own specifications.

  • Non-organic materials, such as metals and plastic, must be kept out.