Kjeldahl Nitrogen Determination Digestion and Distillation Apparatus are offered in classical, rapid and micro models. Kjeldahl analysis is frequently used to determine the protein content of agriculture products. Goldfisch Fat Extractors are used to determine the fat and oil content of samples and are listed in AOAC methods. Crude Fiber Apparatus determine the crude fiber content of feed, food and other agriculture products and are AOAC listed.