Technologies: Food Waste Dehydrators

Commercial vendors are promoting food waste dehydrators to California businesses and institutions that generate large quantities of food waste, such as restaurants, hotels, grocery stores, universities, and prisons. This webpage provides information that may be helpful when evaluating whether this type of technology is appropriate for your facility. CalRecycle strongly recommends that generators contact the entities indicated below, based on the type of technology and proposed end use for material generated, for assistance in meeting local program requirements.

Evaluating the Cost and Return on Investment

When considering the purchase of such a machine, a business owner that generates food waste should calculate the initial and ongoing costs of purchasing a dehydrator and compare it with the cost of separated organics collection service. Although vendors are promoting dehydrators as cost efficient solutions for managing organic waste on site, this may not always be the case. The true cost of the equipment includes:

  • Installation and shipping
  • Electricity needed to operate the unit
  • Ongoing general maintenance and repairs
  • Unexpected repairs due to operator error (such as putting metal utensils in the machine and damaging it)
  • Ongoing costs such as enzymes or additives, if applicable.

Dehydrating food waste reduces weight and volume, which can lead to reduced hauling and disposal costs.

How Food Dehydrators Work

  • Food waste dehydrators operate with electricity and are installed in commercial settings where food waste can be separated from other waste. They are commonly located near the food preparation area.
  • Food waste dehydrators shred food waste and use heat to evaporate moisture. The residual is dried food waste, which is a pulpy mass dry to the touch. The process typically takes a day or less.
  • Do not confuse commercial food waste dehydrators with home dehydrators, which are used for drying fruits, vegetables, and meat for storage and consumption.
  • Dried food waste is not compost. Compost is a stable product that is the result of a complex chemical-biological degradation process. Composting takes weeks or months, not hours or days.
  • If the output is kept dry, dehydrators may also help reduce odors and vectors associated with handling and storing food waste.
  • Dried food waste can re-absorb water. If it becomes wet again, it can grow mold, attract vectors, generate odors, and pose other health and safety problems.

Proper Handling of Dehydrated Food Waste

A business owner should consider whether a food dehydrator can be placed in proximity to people handling food waste. Second, a business owner should also consider how to manage airborne emissions, liquid emissions, and solid output.

Solid Waste Removal Considerations

State regulations do not define dehydrated food waste differently than unprocessed food waste; both are considered solid waste. State regulations require the owner of any business to remove solid waste at least once a week. Check with your Local Enforcement Agency to see whether dehydrated food waste kept in a sealed, vermin- and water-proof container may be eligible for longer holding times.

Solid Waste Handling and Transportation Requirements

Local governments may license solid waste self-haulers. If you are using a food waste dehydrator and intend on hauling that waste, check with your local (city or county) government to determine how to comply with local rules regarding solid waste handling and transport. If you are hiring a company other than your solid waste hauler to haul that material, check their local government licensing status.

Environmental Health Standards for Compost

As previously stated, dehydrated food waste is not compost. However, dehydrated food waste could be feedstock at a composting facility permitted to accept this material type. Dehydrated food may need to be re-hydrated to be effectively composted and should be blended with other compostable materials, such as green waste, and then be composted. Finished compost produced at a permitted composting facility must meet CalRecycle’s environmental health standards before it can be sold.

Land Application Requirements

In some cases, dehydrated food may be a suitable fertilizer. However, fertilizer manufacturers must be licensed and registered with the state if they sell their products and make claims about the nutrient value of the end product or its suitability for use in organic food production. The sale of fertilizers by unlicensed manufacturers is against the law. Fertilizer manufacturers are inspected annually. The California Department of Food and Agriculture’s (CDFA) fertilizer program oversees fertilizer licensing and registration in California.

If the dehydrated food waste is to be directly applied to land, with no claims about its nutrient value or suitability for organic production, then it must meet CalRecycle regulations for land application of compostable materials, which include dehydrated food waste (see CCR 14, Section 17852 (a)(24.5). If compostable material that fails to meet these standards is applied to land, the material is considered disposed. The disposal of compostable material requires a permit. Disposal without a permit is illegal and will result in enforcement action.

In addition to CalRecycle regulations, California Water Board regulations may also apply. Anyone considering sending dehydrated food to direct land application should consult with their Local Enforcement Agency and their Regional Water Quality Control Board to determine what is required.

Other Considerations

Dehydrated food waste may have value as feed for livestock or an ingredient in pet food. Business owners must be licensed, registered, and inspected to be eligible to sell dehydrated food for these purposes.

 

Liquefiers Aerobic Digesters

For more information contact: Food Scrap Management, organics@calrecycle.ca.gov