Malting barley to make the best whisky
Interview with
Making great whisky starts with the malting process, where the best quality barley is steeped in water to start it germinating, so it ramps up enzyme activity and beings to unlock the chemical energy stored in the barley seeds. Chris Smith met up with Richard Broadbent of Station Maltings in the nearby town of Witham, in Essex…
Richard - So we're heading down to our barley intake weighbridge area. Each lorry load of barley that comes to us will weigh around about 29 tonnes, and we have to carry out a number of quality analysis on each load that arrives on site before we tip it and accept it from the farmer. We keep around about 35,000 tonnes of stock at any given point. During harvest, we take in the majority and then we fill up our silos as as full as we can get them. And then as we use barley through the rest of the year, we refill them.
Chris - Now why barley? Why is that so special?
Richard - Barley is the perfect cereal for making whisky. Barley has a very strong husk, which protects the grain during our processing. It has a high amount of starch, protein and enzyme potential, all of which are important to the brewers and distillers later. And our climate is perfect in the UK for growing multi barley as well.
Chris - Where are we going now?
Richard - We'll head up to the barley weighbridge up here, and have a look at some of the barley that we brought in today.
Chris - Lead the way
Richard - So we're in our barley intake lab. So this is where we carry out all the quality analysis on the grain to make sure that the grain that we're seeing on our weighbridge is the grain that we've contracted from the farmer and to make sure that the grain is going to grow in our maltings when we actually get to the point of processing it at some point in the future.
Chris - When you drink a single malt, what goes into that, is it a huge great collection of different barleys that you've started with or do you work in a strict batch? This is one farm, one batch process.
Richard - We would contract with a number of our farmers. So around about this site we probably have about a hundred farmers. We contract certain varieties at certain quality parameters, and then we will bring those in at roughly the same time to then fill up some of the bins that you saw behind us. So we might fill up a 2000 tonne bin with maybe 20 farms of the same variety, the same quality parameters, and we will then process that bin for our customers thereafter.
Chris - So what happens now? You've got a batch of barley, you say it passes muster. What's the next step?
Richard - So after the intake process, we put the barley into our stores and then we recover the barley and make sure that the barley is going to grow when it gets actually into our steep tank. So in the UK we have a very light amount of dormancy in our grain. So it probably grows six or eight weeks after harvest, and then we'll take it to our steep tanks. And the steeping process is the first phase of the malting process. That's where we're going next.
Richard - It's going to be hot. Okay. We'll literally only be in there for a minute then. So we've come up to the first phase of the malting process, which is steeping, which is where we take our raw barley and we add moisture, which initiates the biochemical processes within the grain.
Chris - That's germination, isn't it? You're starting it growing.
Richard - Exactly, so the barley grain is effectively a seed that we are commencing the germination phase of. Each and every one of the millions and billions of seeds in every batch that we make. So we need to add moisture and the steeping process is how we do that.
Chris - Why do you need to germinate it? What does that do that is useful to yielding and releasing what's locked up in that seed?
Richard - The barley grain is starch globules covered in protein. And there is some enzyme there, but it's very low levels. And what we do in the steeping process is hydrate the endosperm. We initiate all the enzyme potential and increase those enzymes and then those enzymes will then break down the protein and they will break down the cell material. So at the end of germination, we have got a much smaller level of proteins. The starch is there, but it's now released from its bound protein matrix that it was in as barley. And the enzymes are all around about the starch. And at that point we put it in our kiln, which is effectively a big oven, to then dry it down and fix that enzymic protein and starch mix that we have created.
Chris - I think I need to grow a bit to see into these tanks, but they're enormous. They must be about four or five metres across these big circular tanks and I can see damp grain in there.
Richard - Yeah, so this batch has been in here for roughly 24 hours. We steep in a new batch every day and this batch will be in these tanks for two days. So we've got another set of steep tanks just through the wall there as well.
Chris - I can see water dribbling into one of the tanks next to us. So basically you put 28ish tonnes or whatever of barley in there and then half fill it up to just soak the grain and then drain that off. And you just repeat that a few times, do you?
Richard - Yes. So we repeat that one more time. So there's the first immersion where we put the grain in and then we fill the water to just above the grain bed so that all of the grain is homogeneously covered in water. And then we rise it a bit to make sure, again, that it's all well mixed. And then that first wet phase might be six or eight hours and then we'll drain it off. And then that's an air rest for, it could be 10 hours. And then we'll again fill the tank with water above the green bed for maybe another six or eight hours. And that second immersion should take the moisture level from the initial starting point of 12% up to say 44% moisture. And then there's a small air rest at the end until it's ready to move to germination. So we'll go to one of the four germination vessels that we have on site.
Chris - Hopefully it's a bit warmer because it's a bit chilly in here.
Richard - It's definitely warmer.
Chris - They're tall, those tanks, aren't they? Because we've just come down all the stairs that correspond to how tall they would've been. So they're quite big.
Richard - Yeah. So I think the green bed is around about three metres deep in those tanks.
Chris - And the conveyors will bring what we were just watching once it's had its immersions, they'll bring it over here.
Richard - Yeah. So they'll take the fully steeped grain. Damp barley effectively that started its germination process. So it's 170 tonnes of that grain along the rubber conveying belts that you can see behind us into the vessel. And we'll load this vessel in about three hours and then we'll look after it in here for four days.
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