We have three large tanks that we use to heat and mix our caramel. Using the settings on the tanks, our caramel is usually perfect, but we don't have any data to log for quality. If it is mixed right and set right, the caramel looks right, we use it. We have recently started talking about quality checks and would like to somehow come up with a temperature range for the caramel so we know we are using quality caramel in our product every time. What equipment might be best to used to check the temperature of the caramel inside the tank? The tank itself is about 4ft tall. Testing from the top of the tank is a simple probe thermometer would be inaccurate.