Let's Talk Maltings

Barley during germination.
You can clearly see the 'Culms' or rootlets

Hi everyone,

Another vaguely interesting and nerdy discussion article, this time on maltings.

Malting barley is the first stage of the process for making malt whisky really. It’s a way of trying to trick the barley into thinking that it’s Spring and that it needs to grow. This ‘activates’ the barley and makes the starch vulnerable to the action of enzymes that can then break the starch into sugars that the yeast needs for fermentation.

100 years ago, the malting would have been done on site at the distilleries. Nowadays, nearly everyone has centralised the maltings or outsourced it to specialist companies and very few distilleries have maltings left themselves.

Just a little on the process of malting before we get into different types…

After the barley is harvested it is dried to about 12% moisture content. At this point, the starch granules in the barley are protected within a protein matrix and cell walls that make it very difficult and inefficient to try and convert it into sugar.

Luckily, the barley has a way of breaking them down for us. The barley would need the starch granules to be accessible when the barley would be growing into a new plant. So we trick the barley by making it think it needs to grow. This is done by soaking the barley (called Steeping) and germination.

The steeping is normally about 48 hours. This involves several water soaks and air rests and the idea is to raise the moisture level from 12% to 45-50%.

The malting floor at Springbank.
The only distillery to malt 100% of their barley.

It can then start the germination where the barley is allowed to grow in controlled conditions. During this stage you can see the barley grow ‘culms,’ which are rootlets and a lot of heat is produced. The barley has to be turned and cool air is blow on/through the barley to keep the temperature constant and allow the barley to grow evenly. This process may be 4-6 days. During this process the barley releases hormones that activate enzymes within the barley. These enzymes then go about breaking down the protein matrix and the gummy cell walls that are protecting the starch.

The peat kiln at Laphroaig.

Another group of enzymes are also activated that start to break down the starch into sugar, called ‘modification.’ This process softens the barely and a classic test of whether the barley is ready is just to rub it between your thumb and forefinger. At the end of the germination the barley should be very soft and it would be very easy to break the barley and rub the starchy innards out.

The final stage is then kiln drying. In the kiln, cool air is used at first and the temperature is slowly raised up to a max of around 80 °C. This will drop the moisture content from 50% down to 4.5%, killing the embryo and stopping the action of the enzymes while also preserving them for later (for the mashing). This stabilises the barley, in that it can be stored for a few weeks at the distillery before it needs to be used.

The drying room above the kiln at Laphroaig

Finally, the barley is deculmed, where the rootlets are broken off and the barley is cleaned before storage and transport to the distillery.

Still with me? No? Ok, let’s keep going…

Over last century, the malting process has gone through a number of advancements and currently there are 3 main types of maltings used in the malt whisky industry. These are traditional floor maltings, Saladin boxes and industrial maltings.

Currently, I believe there are 7 distilleries with traditional floor maltings, 2 with Saladin boxes and only 1 industrial maltings located at a working distillery.

Traditional floor maltings: The most basic and traditional approach. Gravity is often used to deliver barley to the next part of the process, so the building can be a few stories. Barley starts at the top with a steep tank and there are several long concrete floors to lay the barley out for germination. The barley has to be turned by hand or with small machines every 12 hours which is hard work and quite time consuming. There is also much more human error involved and if someone misses a patch of barley, it could easily go mouldy and bring atypical or ‘off’ flavours into the final whisky.

Saladin box: A rectangular box, about 50m in length. The barley depth in the box may be 4ft and it is turned by mechanical screws attached to a moving bar. The bar can move down the length of the box, while the screws spin and move the barley at the bottom of the box to the top. Air can also be blown into the box and through the barley through the flooring of the box.

Industrial maltings: Colossal machines and advanced technology to make the most consistent malt on a large scale. The best explanation can be found here: Port Ellen Maltings Video

The malting floor at Laphroaig

I think the only time I’ve been able to compare whisky from onsite floor malting to industrial has been Laphroaig Cairdeas 2015 to other Laphroaigs, which are mostly from the Port Ellen maltings. The problem is that a smaller amount of floor malted Laphroaig is still used and really, differences in distillation and maturation are going to make a much bigger difference than the type of malting anyway.

The only way to get a true comparison would be to compare the new make spirit from the same distillery from floor maltings and industrial maltings.

Now, what is interesting to me, isn’t so much the process or the different types and how they affect the flavour. It is the time the distilleries moved over to a different type. As I said, every distillery would have had floor maltings at the distillery to do it themselves and these are gradually decommissioned throughout the last 100 years. Some then had Saladin boxes to replace the floor maltings and Glen Ord replaced their floor maltings with a Saladin box in 1961, then replaced that with industrial maltings in 1983.

That’s what you find interesting? Really?

The much smaller malting floor at Kilchoman.
Used for their 100% Islay.

Well partly, it fits into the picture of advancement in the industry and the move from ‘traditional’ to ‘modern’ whisky.

I’ll be doing a ‘Let’s Talk’ article on direct fired stills too, but if you know that Glen Garioch had floor maltings before 1994 and direct fired all it’s stills before 1995, you know that a 1993 Glen Garioch is going to taste quite different from something distilled in 1996.

So in that spirit (Ehhhhhhhh….) I’ve made a list of some the different types and when they stopped, etc. I cut off the floor maltings at 1950 because you could just keep going, also you are getting less and less likely to be able to taste a 1951 floor malted Macallan these days anyway.

In brackets is the year the distillery stopped that type of malting. Where I can, I’ve also include how much of that malting is done on site.

Maltings:

FLOOR

Springbank (100%)

Bowmore (30%-40%)

Laphroaig

Highland Park (20%)

Kilchoman (1 Expression)

Balvenie (15%)

BenRiach (1999)-Restarted Nov 2012

Glendronach (1996)

Glen Garioch (1994)

Ardbeg (1980)

Port Ellen (1974)

Lagavulin (1974)

Talisker (1972)

Glenkinchie (1968)

Glenury Royal (1968, closed 1985)

Glen Elgin (1964)

Aberlour (1962)

Scapa (1962)

Glen Ord (1961)

Glen Moray (1958)

Macallan (1952)

INDUSTRIAL (Drum)

Glen Ord

Port Ellen (Distillery closed 1983, maltings continue)

Glen Esk/Hillside (closed 1985)

Speyburn (1968)

SALADIN BOX

Tamdhu

Tamnavulin

Imperial (closed 1998)

Balmenach (1985ish)

Millburn (closed 1985)

Benrinnes (1984)

Glen Ord (1983)

Dalmore (1982)

Glen Mhor (1980, closed 1983)

Glen Albyn (1980, closed 1983)

Glen Moray (1978)

Ardmore (1976)

Glen Keith (1976)

Thanks for reading! Hope this has been helpful. What do you think? Is there a difference you’ve tasted between malt made onsite or offsite? Traditionally or industrially?