Although lauter tuns are widely employed for wort separation, some large-volume brewers prefer mash filters. Mash filters are very much like plate and frame filters consisting of a series of grid-type plates alternating with hollow frame plates that are suspended on side rails. Each grid plate of the filter is covered on both sides with a monofilament polypropylene cloth. Accordingly, the grist serves no purpose as a filter medium and their particle sizes are of no consequence. Mash filters are more likely to be used in larger breweries where throughput and floor space are priorities.
To initiate the wort separation cycle, the mash filter is flushed, then preheated with hot water. The mash is then pumped from the mash mixer into the filter through the top channel, completely filling the filter frames. The entire transfer to the mash filter is completed in 20 to 30 minutes (33).
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