For a guide to helping you choose the refractometer that is right for you CLICK HERE.
Refractometers are simple optical instruments for measuring the dissolved solids content of fruits, grasses, and vegetables during all stages of growth. The solids that are dissolved in the juice of plant tissues will bend light rays in proportion to: the quantity of all the atoms, the atomic weight of the elements, & the number of covalent bonds in the combinations of atoms such as sugars.
Refractometers have been used extensively in the grape and citrus fruit industries, but are now being used by farmers and consumers everywhere. Refractometers measure in % sucrose by weight (Brix°) and can be calibrated with distilled water and/ or with a sugar standard solution.
For a chart showing Brix° values for some common fruits and vegetables click here brix chart .