Chapter 9


Mashing Equipment

There are a number of configurations of mashing systems employed by brewers. Mashing is performed in a mash tun where the brewer produces and recovers the extract at a single mash temperature or in the special case of a pre-gelatinized or liquid adjunct being employed. If pre-gelatinized adjuncts are not used, a double-mash system that employs a mash cooker and mash tun is required. Although mash tuns can be used for lautering (wort separation), some breweries use lauter tuns for greater flexibility. Temperature-controlled and decoction mashing require separate conversion (mash mixers and mash kettles) and a lauter tun.

Holding Hopper

A holding hopper (often called a scale hopper) is used for grist and is mounted above the cereal cooker or the mash tun.


Premasher is used to mix the brewing water and grist in order to break up the clumps of grist before moving to the mash conversion vessel (i.e., mash mixer or mash tun).

Mash Mixer

Mash mixers or mash conversion vessels are usually stainless steel vertical cylinders equipped with a variable-speed propeller at the base of the vessel used in decoction mashing.

Mash Kettle

A mash kettle or mash cooker is used for boiling part of the mash for decoction mashing. Mash kettles are similar in construction to mash mixers, except that they often have agitators that are more powerful and more steam heated areas, since their contents must be heated to boiling (3).

Adjunct Cooker

Adjunct cookers or commonly known as cereal cookers are used to cook adjuncts such a corn or rice at high temperatures to solubilize the starch. They are usually stainless steel vertical cylinders equipped with a variable-speed agitator.

Mash Tun

British brewers use the same vessel-commonly referred to as the "mash tun"-for both mashing and mash filtration. Mash tuns can only be used for infusion mashing (single temperature) and as a result under-modified malts or malts requiring a protein or glucanase stand cannot be handled.


An underback is a small open topped vessel that allows the brewer to visually check the color and clarity of the wort.

Brewhouse Systems Used by Craft Brewers

Craft brewers use two types of systems in brewing. The first is the traditional "American" style mash/lauter and kettle combination and the other is the "European" style mash/kettle, lauter tun, and whirlpool combination.

Combination Mash/Lauter Vessel and Kettle

Combination Mash/Kettle, Lauter Tun, and Whirlpool

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