Understanding Offal

Offal refers to the waste or by-products of an animal that has been slaughtered and prepared for food. This includes internal organs and other parts that are trimmed during processing. Offal can account for as much as 44% of the live weight of cattle, making its disposal a significant issue in the meat processing industry.

Disposing of Offal and Butcher Waste

Slaughterhouses produce two types of offal: edible and inedible. Edible offal includes a variety of meats such as organ meat. Inedible offal consists of blood tissue, fat, hides, hooves, horns, bones, and lungs. These inedible parts can be:

  • Destroyed by burning or burying
  • Rendered to produce tallow, meat, and bone meal
  • Used as pet food if suitable
  • Converted into products like fertilizer, fuel, animal food, makeup, and even explosives

Considering Disposal Solutions

There are both offsite and onsite solutions recommended by the Beef Cattle Research Council for managing offal and butcher waste.

Offsite Solutions

Deadstock or Offal Pickup

  • Incurs the highest costs.
  • Proper disposal helps control the spread of disease and prevents contamination of air, soil, and groundwater.

Thermal Hydrolysis

  • Expensive with huge energy costs.
  • Completely eliminates products.

Anaerobic Digester

  • Requires the control of prions and is extremely expensive.
  • Converts waste into reusable products, though it is very smelly.

Onsite Solutions

Composting Offal

  • Requires space, time, management, and costs.
  • Improper composting can risk disease.
  • Costs are derived from pick-up per pound, number of pick-ups, and distance traveled.

Composting Process

  1. Animal carcasses are placed in a composting bin or on a straw windrow. A high-carbon bulking agent like sawdust or straw surrounds the carcasses, covered with manure full of microbes. Anaerobic microorganisms degrade the carcasses.
  2. Regularly turn the pile and introduce air to feed aerobic microorganisms, which degrade materials into odor-free carbon dioxide (CO2) and water (H2O).

Burying Offal or Mortality

  • Requires a pit at least 1 meter deep and pre-planning, especially in winter.
  • Risks water contamination in poorly drained soils or high water table areas.
  • Needs to record burial sites and is under provincial regulation.
  • Provides excellent disease control but can be costly.
  • Difficult in cold weather; needs to be prepared beforehand.

Food Waste Digesters

  • Eliminate offal and butcher waste using aerobic digestion.
  • No temporary storage needed.
  • Immediate onsite solution but cannot break down large bones.

Fish waste

Big River Fish (BRF) in Pearl, Illinois, was a major processor of Asian Carp before its closure in 2015. The processing left heads and guts as waste, with typical waste about 700~900 lb per day. Rick Smith, the owner, faced disposal costs averaging $75 per day and sought a more cost-effective solution. He opted for the LFC-200 biodigester, an aerobic food waste digester, from Power Knot.

The LFC biodigester decomposes fish waste rapidly and outputs water safe for sewage systems. It is an on site solution that uses no chemicals and minimal electricity and water. Rated at 240 kg (530 lb) per day, it can consume twice that amount of waste daily, according to the customer.

Offal solutions at the AAMP Convention

Power Knot and Bierman Equipment demonstrated how the LFC biodigester can help eliminate offal and byproducts at the AAMP Convention. They showed how this proven onsite technology can help meat processors and suppliers manage byproducts and offal waste efficiently, reducing costs and environmental impact. Explore how Power Knot’s sustainable waste management systems can revolutionize your operations and contribute to a cleaner, greener future.