Air Classification is the splitting of the light fractions and heavy fractions by forced air, separating the product by molecular weight. This is opposed to screening, which only separates by size.

Here are two additional observations:

1. Classification of poultry meal produces fines with greater amounts of protein and fat and lesser concentrations of ash, calcium and phosphorous.
2. It increases the amounts of amino acids as a % of the protein, with the increase coming with those amino acids considered to be essential. Therefore, protein quality appears to be improved by the classification and aspiration process.

Classification is a process which improves protein levels and increases digestibility while decreasing non-digestible materials. Classification ensures that only the most nutritional turkey parts are used in Regal pet foods. These parts are rich in amino acids - more non-digestible parts are removed. Classification makes a more digestible food - you feed less - you spend less - you have less waste to clean up. That's Regal.

Reference: James E. Osborn, National By-Products, Inc.