M - as in Mashing

What does mashing mean?

Mashing refers to the mixing of crushed barley malt with hot water and the subsequent transfer into the mash tun. At St. Kilian Distillers, this water is taken from the hot liquor tank. When the required amount of crushed barley malt is mixed with hot water, this mixture is called mash. Once this mash is transferred into the mash tun, this process is called mashing. In Rüdenau, the actual whisky production begins with mashing.

How is mash created?

We transport the weighed and crushed amount of barley malt – about 2.2 tons for us – from the grist case via special conveyor systems, such as the trough chain conveyor and an elevator, into our mash tun. The crushed malt first falls into the so-called mashing machine, which is a vertically positioned pipe in which a spindle with attached paddles rotates. With the help of this spindle, the incoming hot water is mixed with the crushed malt falling from above, forming a flowable barley malt slurry – the mash – which is then transported through the pipe into the mash tun.

What needs to be considered when mashing?

It is important to note that the process runs at a certain speed. Mashing should not take longer than 30 minutes. This means that the conveying of the grist and the addition of hot water must be precisely coordinated so that this half-hour period can be maintained. In addition, the mixing must be complete. This is also crucial to avoid clumping, so that the mixture of crushed barley malt and hot water is as homogeneous as possible.

Why is temperature so important?

In addition to optimal timing and homogeneous mixing, temperature plays an enormously important role in mashing. This is because malt contains naturally occurring enzymes that are meant to work during this production step. These enzymes break down the starch contained in the barley malt into fermentable sugars and the proteins into amino acids. The optimal temperature for these enzymes is around 63.5°C. For mashing, this means that the temperature of the incoming water from the hot liquor tank must be set slightly higher so that the mixture with the crushed malt, which enters the mash tun via the pipe, has a final temperature of 63.5°C. Now the enzymes can do their biochemical work.