Abstract: The separation of oats from a combination of grains is performed by obtaining optical data includes both reflectance data and visual data and then analyzing the data in multiple ways, including analyzing information obtained based on ratios of wavelengths and grain imagery. The reflectance data relies on near infrared spectroscopy at requisite ratios of wavelengths in the range of 1100 nm to 2200 nm, while the grain imagery encompasses images of both sides of each of the combination of grains and can also take into account grain size and shape differentiations. The results is an oats separation process wherein at least 99% of foreign grains are rejected with only about 3% of the oats being rejected, while enabling volume processing of grains and establishing a supply of oats with a gluten level well below 20 ppm.