Refractometry is a measure of the percentage of soluble solids content in a sample. This is the total of all the dissolved solids including sugars and salts. Utilised to measure the sugar concentration of fruit the refractometers can give harvest and quality information.

In the food industry the measurement can bring product standardisation, precise mixing proportions, quality and research and development information.

Some refractometers have been designed for specific applications such as the amount of moisture in Honey, percentage of salt, or the concentration of grape must for wine producers.