Raw materials are first mixed and grinded then heated in the extrusion process and then cooled downAlthough this process does not involve any environmentally harmful substances it does require use of energy and some raw materials like fish meal and fish oil are smelly substances

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Raw materials are first mixed and grinded, then heated in the extrusion process and then cooled down.Although this process does not involve any environmentally harmful substances it does require use of energy, and some raw materials like fish meal and fish oil are smelly substances.