Though I highly recommend a meat thermometer, you can still get delicious, fully cooked brats if you don’t have one. Your sausages will be fully cooked when the inside is no longer pink, the casings are golden brown, and, if pierced with a toothpick, the juices run clear. These juices should be free of any pink discoloration. A meat thermometer is a terrific investment, though! It can be used on any variety of meat, poultry, or seafood to ensure that you’re keeping you and your family safe.