Glass-free pH sensorsfrom Mettler-Toledo are being used to control cultivation of starter culture in fermentation reactors. Called the InPro 3300, the sensors enable cheese manufacturers to fully meet strict process safety requirements, as well as comply with various globally recognized standards relating to food protection, production and storage. Instead of a glass membrane, this ISFET-type sensor uses a microchip and the sensor body is made of PEEK material approved by the FDA for food contact. The company offers complete systems consisting of an InPro 3300 pH sensor, an InTrac 797 retractable housing with double flushing chamber, and a multifunctional pH 2100e transmitter.