Document anglais décrivant l'usage de refractomètre pour évaluer la qualité des fourrage, donc les pâturage. Les degré Brix mesure le niveau de sucre dans les jus. Technologie simple et intéressante. / A refractometer is one of many tools which can be used to monitor pasture quality. It uses the known refractive index of a glass prism to measure the refractive index of a liquid, normally the fruit or pasture sap. This is done by either passing light through the sap, or reflecting light off the sap surface, and measuring the angle of the light. A brix meter refractometer is calibrated to give a percentage value of the dissolved sucrose to water ratio in a solution, relative to 20°C. This is called a Brix measurement. However, for example, a brix measurement of 25% means there is 25 grams of soluble content and 75 grams of water in 100 grams of solution. A measurement will be affected by all soluble compounds in a solution, as they all have an affect on the refractive index. Brix measurements are extensi vely used in the fruit and vegetable industry to monitor the quality of produce, for import/export standards and consumer quality checks. They are also used in the wine making industry, where the brix meter is an inv aluable tool used to decide when grapes should be harvested.