Beer needs malted barley. OK, it is possible to make beer completely out of maize, as it is done in some parts of Latin America, or rice, as it is made sometimes in the far east, but nearly all European beer is produced from malted barley. Yes, even the popular mass produced lagers such as Carling derive the majority of their alcohol from malted barley and without that it just wouldn't be beer to the British beer drinker's palate, it turns out.
You always know these days when you are entering a modern industrial site, there is always some sort of safety notice. As we entered the maltings, with the aroma in the air hinting at a rural activity combining with a dash of finished malt resulting in a combined smell similar to old fashioned gummed paper, I noticed the normal "time since last lost time accident" statistics on the large LED display. The memories of Blue Peter style activities, on my grandmothers dining room table years ago, triggered by olfactory stimulant, was interrupted by the realisation that the safety notice also warned us about volcanic ash. As it turned out our guide had only just got back from learning how Molson Coors did malting in the USA and had just flown in, what else could it mean? No flight takes off or lands from this site.
First we were shown where the barley comes in; It has always puzzled me how a seasonal crop was coped with by an industry that has a need for supply all year round. I wondered who took charge of storing the grain until it was required. It turns out that the maltings can store a good bit, out of the 125,000 tonnes it needs per year it can store 100,000 tonnes on site, with a further 9 weeks capacity of finished malt. During harvest the grain is taken in and its moisture adjusted by drying to the optimum for storage. Only for part of the year does the site need to rely on grain producers to store some of the grain.
There are two malting plants on the site. One is a low lying, rather boring looking building. The other one, which is the one that we looked around, is the Tower maltings, which dominate the Burton skyline. It was pointed out that there is a Peregrine Falcon nesting high up on the side of the building. I took pictures of the building as somebody pointed out the bird looking out of the nesting box. As is usual, the bird had flown off by the time I had changed to my telephoto lens. Clearly taking no notice of the safety notice and flying without any regard for the presence of volcanic ash, disciplinary action should be taken in my view.
From the top of the tower a grand view of the town can be gained. Many large tanks, no doubt holding various malted beverages of, if we are to believe the critics, unbelievably short maturation. It scares me to think how much volume is there, and more over, how much volume would be required if Carling was given the amount of "lagering" the purists would like to see.
To make malt the grain is first washed in water, this removes unwanted contaminants from the grain, it needs it, as it has had very little treatment since leaving the farm. This first steeping also increases the moisture content from percentage values in the low teens up into the high twenties or so. The "dirty" water is drained leaving moist, clean grains. A second controlled steeping further increases moisture content to perhaps high thirties where optimum conditions start for germination.
The purpose of malting is to trick the grain, which is a seed, into thinking it is spring and so time to germinate and grow into a plant. This breaks down the cell walls which are holding carbohydrates locked into the grain and optimises levels of amylase enzymes that are later used by the brewer to break down these carbohydrates into sugars, both fermentable and unfermentable.
To enable this to happen a warm moist environment is required, and so the grain is laid out in a circular bed and 100% humidity air blown through. The "air on" temperature is controlled to ensure optimum conditions and moisture added to prevent the corns drying out. The seeds start trying to grow into little plants; they put out rootlets and start to form the beginnings of shoots, or to give them their proper name, acrospires. The bed has to be turned every few hours otherwise the rootlets start to mat together causing a whole load of potentially expensive problems that can only be solved with the use of a manual spade process.
Whilst in this part of the plant our guide explained a key control criteria for malting, that of acrospire development control. DMS, or Dimethyl sulfide, is considered an off flavour in most beer enthusiasts opinions. The precursor to it's production, called SMM, is present to some extent in all malt. Levels in ale malt are generally controlled to as low a level as possible. However, according to Molson Coors, research shows that Carling drinkers actually like that rotting cabbage smell in their beer, they get it confused with sweet corn it would seem, and everybody likes sweet corn. So, contrary to some belief, Carling is actually made deliberately the way it is, because the customer likes it that way. Goody, well done them, make loads of money out of Carling and I get a couple of cast off fermenters - hurrah for DMS, that's what I say.
But back to malt, after these little plants have been allowed to grow a little, just when they think life is getting good we say "oh no you don't", throw them in a dry hot place and kill them. Stopping the germination at just the right time ensures quality beer, and the right time to stop germination is different depending on the end use. The kilning room spreads the malt out in an optimum depth of about 1 - 1.2m. The malster would prefer a thinner bed, but the building would just cost too much to make. Any thicker and the process would be far too energy inefficient. Careful control of finished moisture content is also required. Lager malt requires less energy as the finished moisture content is higher at around 6%. For ale malt the energy required to lower the moisture content to the optimum, around 3.5%, is actual disproportionately higher. Lager malt only needs a maximum air temperature to kiln of 75oC as opposed to ale that requires up to 100oC. Us ale drinkers ought to feel guilty about the increased environmental impact of making ale. We really ought to feel guilty, sadly, I have to report that I do not feel guilty and will continue to drink pongy ale.
I am not at all sure I have done justice here to the very interesting tour we had of the maltings. The twissup day was really made very special mainly due to the hospitality of Molson Coors. Their Brewery Tap bar is great, the lunch they laid on very well appreciated and the ability to buy a couple, or three, halves of P2 quite special. Having said all that, I would have liked to have tried lemon tart and Kasteel Cru too, but it would be churlish to complain, especially as I have two new fermenters to play with.
Oh dear, that took a long time to get written, I'm not even sure it was worth the effort, but thanks for reading the drivel anyway and apologies to Graeme for any glaring technical errors, especially after he made the effort to answer my daft email questions.