Protein measurements are made by mixing weighed samples with known volume of Reagent Dye Solution containing an excess of Acid Orange 12 dye. Proteins in the sample react with the dye to form a precipitate. The remaining unreacted dye concentration is inversely proportional to the protein content of the sample.   
   
The UDY Colorimeter is used to measure the dye concentration and display the percent protein in samples directly. Because a flow-thru cuvet is used, the cuvet does not require washing or rinsing. Sample bottles may be reused without cleaning between samples This measurement does not require calibration with standard samples because Acid Orange 12 dye is easily purified and serves as its own primary standard.   
   
Milk and meat homogenates react in seconds with simple shaking. Dry samples, such as grains, react slowly, but use of the patented React-R-Mill enables a complete reaction to be achieved within one minute. Total analysis time can be as short as 30 seconds for milk and 2 minutes for wheat.