Determining caffeine concentration and TDS

The manufacturing of instant stimulants like coffee and tea has increased during the last decades. The taste of these ingredients depends on the quality and the brand of the raw material, e.g. of coffee beans and tea leaves, but also on how the volatile aroma has been successfully preserved. Instant coffee is manufactured by using a coffee extraction process. During extraction, the coffee beans are grinded and boiled in water. The coffee extract is evaporated and dried by means of spray drying. The coffee powder which passes the filter is dissolved with steam and the recovered liquid coffee extract is returned to the process. Tea leaves go through the same process as coffee beans: extraction, concentration, and drying. The most difficult part in instant tea process is the aroma preserving.

Coffee and tea production with the help of process refractometers

The quality control of coffee and tea can be performed by SCHMIDT + HAENSCH’s refractometers. By identifying the extraction amounts our instruments can determine caffeine concentration as well as the value of the Total Dissolved Solids (TDS). The determination of those values is an accurate and reliable way of ensuring consistent quality during the production process for both coffee and tea. Process Refractometers can be used to measure how efficiently the extraction is. The typical measurement range is 0-30 Brix and the normal process temperature is 5 °C (41 °F).