T - like spent grains

What is meant by spent grains?

In a single malt whisky distillery, the term "spent grains" refers to the solid, ocher to brownish, insoluble residue left on the screen bottom of the mash tun after mashing or lautering malted barley.

How does the spent grains get out of the mash tun?

The sieve bottom of our Mash Tun contains a hatch that can be opened after lautering. Through this opening, the mash residue, which is still about 80°C hot, falls down into a small stainless steel storage tank. With the aid of the rotating rake in the lauter tun, the entire quantity of spent grains is discharged in this way.

Where is the spent grains collected?

The spent grains are stored in a spent grains silo of about 25 tons, also made of stainless steel, which is located outside the production building behind our three malt silos.

How does the spent grains get into the silo?

Already during the discharge of the spent grains through the bottom hole in the Mash Tun, this mass is first continuously conveyed further in a pipe by means of a screw conveyor and then, with the aid of air pressure generated by a compressor, transported intermittently pneumatically through a pipeline with a diameter of about 20 cm to the spent grains silo.

What happens to the spent grains?

Since the spent grains contain all the solid and insoluble components of the malt grain, such as fibers, proteins, oils, trace elements as well as some vitamins, they are very rich in nutrients and thus a welcome feed supplement for our domestic animals. For this reason, the spent grains are picked up once a week by farmers from the nearby area with tractor and trailer. A nice cycle back to nature.