Since its introduction in 1959 there have been changes in configuration and operation giving improvements in extract yield and number of brews per day. Over 30 Strainmasters are currently in use throughout the world. It has proved to be the fastest means of extracting wort from the mash. Originally round, but later changed to a rectangular vessel, the Strainmaster incorporates rows of slotted tubes for wort draw off. Mash is introduced at the top and distributed along the length of the vessel through a header with equally spaced nozzles. Recirculation is started when the top row of tubes is covered and is completed by the time the mash is all received. As soon as the wort is clear it is fed by gravity to the kettle. First wort run off is at 12 to 15 brl/min. Sparging is commenced when the liquid level is ca 3 inches above the grain bed. Level and temperature are controlled automatically and the flow during sparging averages 7 to 8 brl/min. Removal of spent grains has been speeded by changes in configuration and tube arrangement and now requires about 10 min. The original design operated at 10 brews per 24 hr. Improvements, together with other brewhouse innovations, enable up to fifteen brews per 24 hr to be achieved. At this higher rate recovery efficiency falls from 94 to 96% to 90 to 92% and this must be set off against the increased production per man hour.
Keywords: brewhouse brewing equipment mashing strainmaster survey