Rendering systems for processing animal by-product materials

Abstract

These systems are divided into two classes, edible rendering of animal fatty tissue into edible fats and proteins for human consumption, and inedible rendering of animal by-product materials into animal fats and proteins for animal feed and other non-edible applications.

The inedible rendering process consists of two basic steps: “cooking” or moisture removal by evaporation, and separation of the melted fats from the protein solids. The basic rendering process involves the use of batch cookers. In recent years, continuous rendering systems which utilize continuous cooking have replaced many batch systems. These continuous systems are described.

A continuous system is described for edible rendering. This system features two stages of centrifuges: 1) a horizontal, solidbowl centrifuge for separation of protein solids from the liquid, and 2) a disc centrifuge for separation of the edible fat from the sludge phase consisting of protein fines and water.