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Reducing Food Waste: Compost Production Recovers Nutrients for Soil Benefits

By Debra Atlas

When you consider our nation’s health, the quality of our food, its decreasing nutritional value and the increased degradation of our farmland, it’s not a pretty picture — and the challenges related to these issues keep growing.

By 2050 the world’s population will likely reach close to 9 billion people. To feed everyone, we’ll need to globally produce more food. Yet, almost 40 percent of food currently produced ends up in landfills.

According to ReFED, a collaboration of over 50 business, nonprofit, foundation and government leaders committed to reducing food waste in the United States, American consumers, businesses and farms spend $218 billion per year growing, processing, transporting and disposing of food waste.

Food waste is a global problem. The 2017 Food Sustainability Index ranks 34 countries from best to worst. In France, No. 1 on the Index, supermarkets don’t toss food approaching its sell-by date; they must donate it to charities or food banks. This has lowered the country’s annual wastage to 1.8 percent of its total food production. Germany, Spain and Italy, which follow close behind, also scored high with agriculture-related conservation and research and nutrition education.

The United States, however, falls into the third quartile, ranked 21 out of 34 for food sustainability. But this is a story of possibilities — one where innovation is helping create solutions to a problem that could dramatically affect our future. If we are to meet the food needs of an increased population sustainably, we must do things differently. Composting — using food scraps to add nutrients to soil — is a good first step.

According to BioCycle Magazine, around 200-300 cities have food composting programs in place. The San Francisco Bay area’s urban compost collection program, possibly one of the largest in the country, began in 1996 to reduce landfill disposal and turn food scraps into compost. Other U.S. cities with compost-collecting programs include Denver; Austin, Texas; Portland, Oregon and New York City.

Green waste used as part of a mixture of ingredients for compost.

Benefits of Reducing Waste

The Harvard School of Public Health said reducing food waste by an estimated 15 percent could feed more than 25 million Americans annually. You would think this would be a driving incentive for waste reduction. But how does food collection figure into soil health? Simple. The quality and health of the soil determines the quality and yield of the crops planted in it.

“You can view compost as a food,” said Bob Shaffer, agronomist, soil scientist and 40-year farmer. “It’s a high-quality, diverse food that’s able to give you health.”

Shaffer, who works to improve soil health by increasing organic matter and nutrient levels on large and small farms around the world, says there are many stresses on soils and our food systems.

Degraded soil comes from a lack of calcium, nutrients and food for the microorganisms that plants need in order to grow. To turn soil “soft” again, says Shaffer, requires organic management, tillage management and nutrient management. “The soil needs to be fed,” he said. “The soil is the big prize.”

Composting waste is crucial to soil health. Shaffer says all the organic matter available should be applied at the farm level. He is dismayed at the sheer volume of recyclable material found but not used on farms today.

Every ton of collected food scraps yields 1 to 1½ cubic yards of compost — approximately 1,000 pounds per cubic yard.

Composting reduces the starting material from 50 to 60 percent. The 40 percent of food we waste each year presents a huge opportunity to revitalize degraded farmland.

The question we should be asking, said Shaffer, is: What can we recycle and/or compost? “There’s so much organic matter that goes to waste. We should recycle all these materials and put them to use. We need zero waste and all the materials brought to the farms to be composted and returned to the soils that are providing food to the cities. If it doesn’t come from the city to the country to be composted, we’ll continue to have degraded soils.”

Composting processes vary, including:

  • Static aerobic compost.
  • Thermal compost, which employs heat to create compost.
  • Vermicomposting, which uses worms to turn food scraps into nutrient-rich compost.

Whichever process is used, Recology, a San Francisco-based integrated resource recovery company, knows that adding compost to soil offers a cornucopia of benefits:

  • Keeps materials out of landfills, saving landfill space and reducing landfill emissions such as methane and other potent greenhouse gases.
  • Returns nutrients and minerals to farms to keep soils fertile.
  • Promotes microbial activity in topsoil, which switches on the soil food web, making micronutrients available to plant roots and discouraging diseases.
  • Helps protect topsoil from erosion.
  • Saves tremendous amounts of water. Good quality compost is 50 percent humus by weight, and humus is a natural sponge that attracts and retains water. This minimizes the need for irrigation and artificial fertilizers, which could have harmful effects on the world’s oceans and other waterways. Building up the water-holding capacity of soils can help farms weather droughts. If you increase organic matter by 1 percent on 1 acre of land by adding compost and employ eco-farming management strategies, we can save 16,500 gallons of water per acre per year.
  • Sequesters carbon deep in the soil, especially when used to grow cover crops which shade topsoil.
  • Creates three times more jobs than landfilling.
  • Helps cities make progress toward achieving zero waste.
  • Helps clean up contaminated soil by binding heavy metals and preventing them from migrating to water resources or from being absorbed by plants.
  • Turns food scraps and plant cuttings into fruits, vegetables and even fine wines.

Shaffer says education is crucial for more people and farmers to get on board with composting. It’s about educating municipalities and individuals who buy our food and then don’t recycle it about why we want it as compost, he said.

“We lose a lot of opportunity with consumers who don’t participate in food recycling. It doesn’t make sense to them until it’s explained.”

Composting in Action

In 2017 Baltimore’s National Aquarium partnered with Colorado-based Eco-Products (a certified B Corporation) to help turn guests’ trash into rich, fertile soil rather than have it end up in local landfills. The aquarium replaced all its conventional disposable plastic foodware products with reusable, compostable or other sustainable choices. These get turned into nutrient-rich soil and mulch for area farms, gardens and for the waterfront park that surrounds the aquarium.

Companies like ChicoBag and Sierra Nevada Brewery incorporate on-site composting to reduce food waste. Napa Valley California’s award-winning Chateau Montelena Winery has been applying compost and planting cover crops in their vineyards for almost 20 years. “And they have healthy, consistent crops,” said Shaffer.

One of the largest onion growers in the country is based in King City, California. Composting is a big part of his operation. The grower says he wouldn’t grow onions without it, and he uses his onion processing waste to give back to the soil.

Shaffer works with large banana growers, rice growers, grape growers and tomato processors who recycle their organic matter into compost for their operations. Shaffer worked with General Mills to set up an operation in northern California where they process the 2,500 acres of organic tomatoes they grow. They process the tomato skin and seeds from their pulped canned tomatoes.

Compost applied to vineyard soils.

Shaffer noted that tomato seeds have about 4 percent nitrogen. “This recycled waste makes a great source of compost feed stock,” he said.

The federal government has gotten involved in the food waste issue. In 2013, the U.S. Department of Agriculture and the Environmental Protection Agency launched the U.S. Food Waste Challenge.

They called on entities throughout the food system — including farms, agricultural processors, food manufacturers, grocery stores, restaurants, universities, schools and local governments — to get involved.

In December 2014 the Agriculture and Food Research Initiative (AFRI) and USDA’s National Institute of Food and Agriculture competitively funded a first-of-its-kind conference on food loss and waste in the United States; The Last Food Mile Conference: Food Loss and Food Waste in the U.S. Supply Chain. Its purpose was to define the state of knowledge, understand the factors affecting behavior, identify critical control points and build a network of research and intervention strategies to address food waste.

During this same timeframe, the USDA recognized innovation as a major driver in increasing the reduction, recovery and recycling of food waste. It saw innovation as helping to make reducing, recovering and recycling food waste economically viable for businesses, organizations and households by increasing the feasibility or reducing the cost of better food waste management.

In September 2015, for the first time both the USDA and the EPA announced a national food loss and waste goal, calling for a 50 percent reduction by 2030 to improve food security and conserve natural resources. They recognized that innovation could help stimulate economic development and job growth by turning food waste into an economic opportunity.

USDA’s Agricultural Research Service is designed to support innovation, often in collaboration with industry and academic partners, by conducting research on new technologies for reducing spoilage of fresh foods and for the development of new products from waste materials at food processing facilities.

San Francisco-based Full Harvest Technologies, Inc. is one of the companies filling this niche. Their goal is to solve food waste at the farm level with technology. In 2017, it secured funding so it could offer the first business-to-business marketplace to purchase and sell surplus and imperfectly shaped produce.

Full Harvest aims to turn the billions of pounds of produce that go to waste each year due to surplus or cosmetic reasons into a new profit center for the industry. They plan to help growers recapture the estimated $10 billion market of lost produce sales by selling excess produce to food and beverage companies while lowering costs for those companies and for consumers, and have farmers receive additional revenue.

“Excessive food waste creates an enormous burden on our society, economy and environment,” said Christine Moseley, founder and CEO of Full Harvest. “With the knowledge and technology we now have at our fingertips, no food should go to waste. Our goal is to be the Alibaba of produce — a universal, easy-to-use platform that allows growers, food and beverage companies and retailers to benefit from excess farm produce.”

Rich healthy soil is essential to producing better quality crops and healthy nutritious food.

The more we reduce food waste and turn it into compost applied to farmland to improve soil health, we ensure that our farms will be able to meet the food demands of a growing world.

Editor’s Note: This article appeared in the October 2018 issue of Acres U.S.A. magazine.

Debra Atlas is a freelance journalist and professional blogger.