Brix (written °Bx or degrees Brix) is a scale used to express the soluble-solids concentration of an aqueous solution. In a pure sucrose solution, 1°Bx is equivalent to 1 gram of sucrose in 100 grams of solution. In foods such as fruit juice, syrup and wine must, a Brix reading is commonly used as an estimate of dissolved sugar, but other soluble substances can affect the result.
A refractometer measures how light bends as it passes through a liquid and converts that reading to a Brix value. Hydrometers can also estimate soluble-solids concentration from liquid density. Instruments should be calibrated and used according to the manufacturer’s instructions; temperature compensation and sample temperature matter for reliable readings.
For a pure sucrose-water solution, the Brix value corresponds closely to sucrose percentage by mass. In fruit juice, honey, dairy and other complex foods, refractometer readings are better described as apparent Brix because acids, minerals and other soluble solids also influence refraction.
Chef’s tip: use Brix to compare similar products or monitor a recipe consistently. For precise nutritional sugar content or food-safety decisions, use an appropriate laboratory method or validated process rather than relying on Brix alone.
This term is one of hundreds covered in depth across OCS courses, learning paths, and 1-on-1 coaching with Chef Eric.
