Malt Milling(book excerpts)
The objective of milling is to reduce the malt to particles sizes, which will yield the most economic extract (wort) and will operate satisfactorily under brewhouse conditions and throughout the brewing process. The more extensive the malt is milled, the greater the extract production. However, the fine grind can lead to subsequent wort separation problems and a loss of extract in the spent grains during wort separation. As a result, the brewer needs to consider the equipment used in the brewhouse when determining the particle size when milling the malt. For example, mash tuns require comparatively coarse grists while lauter tuns can use finer grists and mash filters still finer grists.
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