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**1. Mashing Techniques:**
Infusion Mashing:
– Most breweries use direct heating for infusion mashing.
– Temperature changes achieved by adding hot water.
– Single-step infusions involve only one rest before lautering.
– Decoction Mashing:
– Involves boiling a portion of grains and returning them to the mash.
– Classifications include one-, two-, and three-step decoctions.
– Traditional method in German and Central European breweries.
– Enzymatic Rests:
– Different temperatures allow specific enzymes to work optimally.
– Optimal temperatures for major mashing enzymes vary.
– Thick mash acts as a buffer for enzymes.

**2. Equipment and Processes:**
– Mash Tun:
– Large breweries use dedicated vessels called ‘mash tuns’ for mashing.
– Heating method based on steam to avoid scorching the malt.
– Proper insulation maintains rest temperatures for up to an hour.
– Mashing-in:
– Mixing of strike water and grist must minimize clumping and oxygen uptake.
– Mashing in must be done at specific temperatures for enzyme activity.
– Decoction Rests:
– Part of the mash is taken out and boiled to caramelize sugars.
– More starches are freed from the grain, leading to efficient extraction.

**3. Mash Rests and Temperatures:**
– Enzymatic Rests:
– Contention exists in the brewing industry regarding optimal enzyme temperatures.
– Enzymes become denatured and inactive after completing their step.
– Decoction Rests:
– The portion drawn off is calculated to reach the next rest temperature.
– The thick mash is boiled for around 15 minutes and returned to the mash tun.
– Mash-out:
– Mash is raised to its mash-out temperature after enzyme rests.
– Exceeding 78°C can cause starch haze and harsh flavors.

**4. Benefits and Results of Mashing:**
– Decoction Mashing:
– Results in unique malty flavor due to Maillard reactions.
– Intensifies malt profile in Bock or Doppelbock beers.
– Mash-out:
– Frees up about 2% more starch and reduces viscosity.

**5. Additional Information and Resources:**
– Etymology:
– Term ‘mashing’ originates from Old English words meaning soft mixture and mixing with hot water.
– Usage of the term dates back to the late 16th century.
– See Also:
– Drink portal
Technology portal
– Grain bill
– Wort
– Sour mash.

Mashing (Wikipedia)

In brewing and distilling, mashing is the process of combining a mix of ground grains – typically malted barley with supplementary grains such as corn, sorghum, rye, or wheat – known as the "grain bill" with water and then heating the mixture. Mashing allows the enzymes in the malt (primarily, α-amylase and β-amylase) to break down the starch in the grain into sugars, typically maltose to create a malty liquid called wort.

A close-up view of grains steeping in warm water during the mashing stage of brewing

The two main methods of mashing are infusion mashing, in which the grains are heated in one vessel, and decoction mashing, in which a proportion of the grains are boiled and then returned to the mash, raising the temperature.

Mashing involves pauses at certain temperatures (notably 45–62–73 °C or 113–144–163 °F) and takes place in a "mash tun" – an insulated brewing vessel with a false bottom.

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