Digital Refractometer for Sugar (% Brix) Analysis in Must and Juice

This Hanna Instruments digital refractometer measures sugar content in grape must and fruit juice, in degrees Brix.

Why it is measured

Brix in the must is what sets the alcohol the wine will reach, and it is the number that decides when fruit is picked. A grower walking a vineyard needs it from a drop of juice, in seconds, in the sun.

Where it is used

• vineyards at harvest
• wineries
• fruit juice production
• fruit maturity assessment

How a refractometer works

Light bends by a different amount depending on how much is dissolved in a liquid. A refractometer measures that bend and converts it to a concentration scale. It needs one or two drops, gives an answer in seconds, and has no reagents and nothing to consume.

A digital instrument compensates for temperature automatically, which is the difference that matters: refractive index shifts with temperature enough that an uncompensated reading in a warm room is simply wrong.

Practical note

Sample several berries from different parts of a vine and different parts of a block; one grape is not a vineyard.

Supplied as one model.