So Matt, Molly and I took a little day trip down to Newton Abbot to do a massive amount of geeking out about all things barley. I actually managed to take some notes despite the 6am train journey!
Tuckers Maltings was established in 1831 which makes it fairly well established! It’s one of only four traditional floor malting works left in England. Contrary to conventional malting which can be completed in a matter of days, Tuckers take 10 days to process a batch of malt using traditional practices and a lot of heavy lifting!
Gareth was kind enough to take us through the whole process from start to finish and we were pretty astounded by the care and hard work that goes in to every batch.
Tuckers process 1500 tonnes of malt per year – primarily Pale and Lager Malt although they do buy in Crystal and other speciality malts to supply to brewers.
They process two main types of barley – spring and winter.
Winter varietals are sown in October and spring varietals generally sown after Christmas.
Winter Varieties include the ever popular Maris Otter: an old variety, highly regarded for flavour and ease of use in brewing. Robin Appel owns the rights to Maris Otter. Extract is quite low and grain size quite small but Maris creates a good grain bed and filters well so is popular for use in brewing as it makes it easy to avoid a stuck mash. Brewers also swear by its complex flavours.
Spring Varieties are generally bred for better yield and extract. They also boast better disease resistance. New varieties are continually developed and are being experimented with Propino being very popular currently and Concerto, Westminster, Oddessy and Irina all having had their time in the limelight in the last few years.
When arriving at the malthouse, the moisture content of the grain kernels is usually at 16% total mass with a target of 12% moisture for storage. Tuckers drying drum will eliminate 1% of moisture content per hour and as such is very gentle and will not negatively impact upon germination – which used to be a problem for maltsters who would dry grain for storage by using their kilns.
Grain size sorting. Grain is passed through a hopper to a barley screen, made up of a series of sieves which shake and vibrate the kernels.
Screenings, thin and half corns, are separated and bagged off, as uniform grain intended for the germination floor passes over these sieves. Waste and screenings are then used for animal feed.
FUN FACT: Barley grows best with warm wet weather early on and sunny weather later on with the odd shower = optimum harvest.
Steep tanks
These hold 8 tonnes of barley with 1500 gallons water. Some lighter grains will float to the surface and run off, leaving the more suitable kernels behind.
The grains are soaked from 12% to 45% moisture content.
The process is fairly straightforward: fill with water, soak for 12 hours, drain, sit for 12 hours, drain. It generally takes 2.5 days to soak and reach desired moisture content.
The kernels are now drained through this perforated bottom – which is 117 years old!
The barley then spends 3 days on the germination floor.
The winter floor will be spread quite thick ly (up to 25cm) and the summer floor thinner (approx. 15cm) to maintain an optimum temperature for germination (not above 60F).
The germinating malt is then turned twice per day and ploughed twice per day.
Heating up the floor in winter can be difficult and space heaters are sometimes used – if the floor is too cold (for instance after the Christmas break) the barley will not germinate properly.
Temperature control is used throughout the malthouse – in the past they would stop malting for summer. The buildings walls are at least a foot thick throughout both to maintain internal temperatures and to support the weight of the equipment and grain. The windows here are also boarded up so that sun can’t get in and warm the place up too much.
As there is a lot of humidity in the germination floors, damp control is necessary and routine.
Tuckers use a mechanical winch (Reddler Power Shovel) to move grain from the germination floors to the kiln.
This grain barrow is used to dump malt and spread over the germination floor.
A chain and bucket elevator then carries grain to the kiln.
Tuckers used to have four kilns but now use only two – freeing up space for storage and loading pallets.
Originally fueled by anthracite coal, the kilns changed to oil in the 60’s and to gas in the 80s. Samples are regularly sent off for laboratory tests as this kiln is direct fired. Particularly important is the identification of NDMA (nitrosamines) which are known carcinogens.
FUN FACT: Maris Otter has smaller kernels than most spring varieties.
Green malt is now spread to an even level (about 30 – 45cm) in wedge wire flooring above the spark chamber and the kilns are switched on.
Lots of steam is produced on the first day of kilning as moisture within the malt is evaporated. Because of this the roof vents are left open for 12 hours.
On the second day the roof vents are closed. The 1984 recirculation system saves thousands of pounds by reusing the heat produced by the kilning process
Lager temperatures in the kiln start at 60F, 2nd day steps up to 70F.
Pale starts at 65F and steps to 70F for 2nd day. Steps to 76-78 for drying off.
EBC units for lager = 2-3 and Pale = 3-4
Tuckers used to make Munich malt for St Austell’s Cornish Gold. The process required firing up the kiln and running it for 6 hours before shutting off. The malt would sit warm and damp and sweat. Through this process it picks up more colour and gains richness. Then the kiln is fired up to over 90C to finish off the process.
An aluminium power shovel is used to save floor from scratching.
After kilning, malt is sent over these sieves in a tumbling motion, breaking off and separating the fat kernels from the rootlets and dust (culms).
Malt culms contain 27% protein. They are usually sent off for animal feeds.
Malt dresser – this awesome old piece of perfectly functional equipment consists of a series of brushes to remove rootlets or dust from the grain.
The finished malt is then bagged up and sent out!
FUN FACT: Tuckers building was electrified in 1915. It used DC electric motors until 2006.
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