A method is provided for determining a physical property of a malt beverage sample. The method includes measuring a refractive index of the malt beverage sample. The method further includes determining a temperature-compensated measured refractive index by temperature correcting the measured refractive index relative to a predetermined reference temperature. The temperature correcting is specific to the total dissolved solids of the malt beverage sample. The method also includes converting the temperature-compensated measured refractive index to a unit of measurement. The unit of measurement relates to a physical property of the malt beverage sample. Apparatus are also provided.