In animal agriculture, rendering is the process of repurposing byproducts from slaughter as an additional form of revenue for the industry. Rendering typically involves heat treatment to transform byproducts and destroy pathogens, removing moisture and separating solids from fat (https://www.ausrenderers.com.au/en/what-is-rendering/).

As a result of the sheer amount produced by the animal agriculture industry, animal byproducts are used in several household and industrial items, including soaps, cosmetics, medications, tires, fertilisers, floor waxes, plastics, insulation, dripping and many more (https://www.pridham.com.au/rendering/, https://www.renderingbyproductsaust.com.au/what-is-animal-by-product-rendering, https://agriculture.institute/meat-animals-abattoir-practices/overview-products-rendering-animal-by-products/#tallow-the-versatile-fat-from-cattle-and-sheep).

Many large slaughterhouses have their own, on-site rendering plants. While smaller slaughterhouses will truck their waste to off-site plants.

The parts of an animal rendered

Animal byproducts used in rendering include the following:

• Bones
• Fat trimmings
• Organs
• Carcasses
  

(https://agriculture.institute/meat-animals-abattoir-practices/overview-products-rendering-animal-by-products/#tallow-the-versatile-fat-from-cattle-and-sheep)

The result

Once these byproducts have been rendered, they become tallow, lard and oils, along with meat, bone, feather and blood meal (https://agriculture.institute/meat-animals-abattoir-practices/overview-products-rendering-animal-by-products/#tallow-the-versatile-fat-from-cattle-and-sheep, https://www.ausrenderers.com.au/wp-content/uploads/2023/09/ARA-Rendering-Fact-Book.pdf), which will then be combined into products and sold to the public. 

Revenue

From 2015/2016, approximately 1.25 million tonnes of rendered products were produced from 2.7 millions tonnes of raw byproducts, which resulted in a total value of $880 million. (https://www.ausrenderers.com.au/wp-content/uploads/2023/09/ARA-Rendering-Fact-Book.pdf)

References 

-https://www.ausrenderers.com.au/en/what-is-rendering/

-https://www.pridham.com.au/rendering/

-https://www.renderingbyproductsaust.com.au/what-is-animal-by-product-rendering

-https://agriculture.institute/meat-animals-abattoir-practices/overview-products-rendering-animal-by-products/#tallow-the-versatile-fat-from-cattle-and-sheep

-https://www.ausrenderers.com.au/wp-content/uploads/2023/09/ARA-Rendering-Fact-Book.pdf