Automatic periodic sampling and analysis of beer during fermentation - for improved quality control of large scale automated brewing

摘要

The sample is automatically prepd. and analysed to determine the proportion of volatiles. Each of several sampling circuits in turn is switched through a three-way valve with rinsing branch and single delivery to the coil of a temp. regulating bath. The sample is then piped tangentially into the base of a sample prepn. vessel. The vessel has an inlet for injection of pressurised inert gas and an outlet leading to a gaseous phase chromatography analyser. The installation is automatically sequenced by a process control programme unit. Circuit rinsing is automatic between sampling operations. The sample prepn. vessel pref. has a gas inlet diffuser near the base of the vessel, as well as a liq. level detector controlling the level via signals to the programme unit. The carrier gas is pref. carbon dioxide. The temp. regulating bath is pref. fitted with both refrigerating and heating elements. Used for automatic, regular sampling of beer during the course of fermentation followed by precise, gaseous phase chromatographic determn. of proportion of volatiles. The process provides the frequent, e.g. 4-hourly, monitoring of fermentation necessary to assure reliable quality control of automated brewing operations. A single analyser efficiently serves several fermentation tanks, pertic. three three or four outdoor tanks each with a capacity of several million litres.