The rendering industry processes most animal by-products from the meat production chain which do not end up on the consumer’s plate. These vary from country to country dependent on the eating habits of different cultures. In the western world, this represents almost one third of the weight of animals slaughtered (more than 1.75 million tonnes in the UK only each year, producing 250,000 tonnes of fat and 400,000 tonnes of protein meal).
The rendering process is the crushing and grinding of animal by-products, followed by heat treatment to reduce the moisture content and to kill micro-organisms. Separation of the melted fat (tallow) from the solid (protein) is achieved through centrifuging (spinning) and pressing. The solid fraction is then ground into a powder, such as meat meal or meat and bone meal.
Although rendering as an organised and cohesive industry has been around for only 150 years, the process of melting down animal fats to produce tallow and other fats and oils probably started when man began cooking meat over a campfire and saving the drippings. Historians have charted soap and candle-making from the products of rendering, with one of the first accounts of rendering being written by a Roman soldier.
In recent times, the industry has made an important contribution to our effort to maintain a clean and healthy environment. In addition, it turns otherwise unusable material into usable commodities, for example tallow for soap production and the manufacture of base chemicals and animal protein for livestock nutrition.
State-of-the-art technology, strict regulation and a real sense of commitment and responsibility for the environment mean that today’s rendering operations are highly technical and require very high levels of investment.