Until the Industrial Revolution there was only one kind of malt. So we were told by maltsters at the seminar we attended a couple of years ago. It had been organised by the Orkney Science Festival and was held at the Highland Park Distillery. Only twelve tickets available, so we were very lucky to be there!
Malt has been made using the ancient and traditional techniques of steeping, aeration and floor malting for thousands of years. Grains such as wheat, barley, rye, millet or oats can be malted. Making malt was probably one of the first grain processing techniques, going right back to the earliest grain agriculturalists of the Fertile Crescent, at least ten thousand years ago and maybe more. What is floor malting? Harvested grain is steeped and aerated before being partially germinated. Most importantly, drying the green malt must be done very slowly and carefully. This is how a base malt, known also as diastatic malt today, has been made for generations upon generations.
This kind of malt is not roasted or toasted at high temperatures.
Why not? Because roasting the malt at too high a temperature destroys the enzymes within the germinating grain. These enzymes are essential to convert starch into sugars later in the brewing process, that is, in the mash tun. Although the scientific explanations of grain germination, the biochemistry and the physiology, have only been understood since the 1960s, maltsters have known the importance of keeping the 'spirit of the grain' alive throughout the malting process. From steeping to kilning, maltsters have known what to do for a very long time. Henry Stopes' classic study of the practices, processes and technicalities involved in making good malt and malting technology (published in 1885) is a book that I repeatedly refer to. In his first chapter there are several descriptions of how malt was made in medieval times and earlier. I especially like this one, where it is clear that the early maltsters definitely knew how to handle the germinating grains:
"the grain was steeped and germinated, by which its spirits were excited and set free; it was then dried and ground and infused in water, when after [it was] fermented."
by Geoponius? cited in Henry's History of England, see Stopes (1885)
To make good diastatic or base malt you have to do the right things in the right way, using suitable temperatures and having the correct conditions for each stage of the process. Making malt is a craft. It requires specialist knowledge, skill and experience. There's a lot more to it than just sprouting a few barley grains in a jar in the cupboard under the sink, or in a warm place. The maltster's knowledge, experience and skill means that they can steep, aerate and partially germinate very large quantities of grain without it going mouldy or bad.
Modern specialty malts, such as crystal malts, amber malts and chocolate malts are roasted at high temperatures, but these only began to be made around the 17th/18th century. They are a modern technology, used to add colour and flavour to beer. They do not provide fermentable sugars. Roasted, toasted specialty malts came about because of a change in the fuel used to dry the malt. The Industrial Revolution introduced a new fuel: coke. Practices changed from using from wood or straw to dry the malt to using coke, the result being a paler malt than was previously produced.
So, to cut a very long and complex story short, malts began to be roasted and toasted at around the time of the Industrial Revolution in order to make ale and beer the colour that consumers were accustomed to. Specialty roasted, toasted malts are not a technology of the Neolithic, Bronze Age, Iron Age, Viking or Medieval eras.
What has any of this to do with archaeology or archaeobotany?
Well, I've just read yet another paper where the archaeobotanical report incorrectly uses the terms toasted or roasted sprouted barley when considering that the carbonised cereal grains and fragments of grains discovered there could have been malt for brewing purposes. This paper was published in the specialist archaeobotanical journal Vegetation History and Archaeobotany in December 2017. So there is little chance of it being read by a maltster. It's well worth reading because this is some of the best evidence yet discovered for malting. It is a shame that the descriptions of how to make malt, how to mash and ferment into beer are misleading and confused. More on that later. It's possible to contact the author and get a copy. That's what I did. Here's an extract from the abstract:
"Archaeobotanical remains of sprouted cereal grains as well as cereal fragments from the Bronze Age sites of Archondiko and Argissa on mainland Greece, presented here for the first time, provide strong indications for the making of something similar to beer in late 3rd millennium BC Greece, opening up a series of new questions about the recipes followed in this process and their origins."
What about those words sprouted cereal grains? To many people, they suggest growing long bean sprouts, the sort of thing we grew in school in Biology lessons, but that is not what malt is. Malt is grain that has only just begun to grow. The acrospire should be about three quarters of the length of the kernel or perhaps a little bit more. Too much growth and all of the grain starch will be used up and there will be nothing for the mash tun.
This kind of description of malt as toasted roasted barley sprouts has been repeated over and over again in the archaeological and archaeobotanical literature, in excavation reports and elsewhere. The idea that to make malt for beer brewing in prehistory, the grain was sprouted and then roasted or toasted in a very hot kiln is incorrect. However it's a very common explanation. It doesn't seem to be tied to any particular era, I've read papers and excavation reports that discuss sites from the Neolithic to the Iron Age and beyond. They usually say, that is, if malt is even acknowledged as being part of the beer brewing process, that the grain was sprouted and then roasted or toasted to make malt.
In the article on Booze! in National Geographic magazine (February 2017) brewer's malt is described by the journalist, Andrew Curry as sprouted toasted barley grains. Not being a malting or brewing expert himself, he has clearly relied upon information given to him from brewers, such as Martin Zarnkow who he interviewed for this article. Zarnkow has attempted to recreate Sumerian beer on the laboratory bench using malt mixed with unmalted grain and using sourdough as a starter for fermentation. He claims he can make alcohol overnight. It is a strange recipe for beer.
Incidentally, there are some rather odd recipes for ancient beer around. For example, Professor Patrick McGovern's most recent book, Ancient Brews, uses malt extract (a Victorian invention), specialty malts and other unusual ingredients for an ancient ale. When he was recently interviewed by Beersmith, the Professor acknowledges that he has never actually made a beer from the grain and that perhaps he should try it, for the experience. I'm wondering, how can he be a beer expert when he has no experience of making beer from the grain?
Ancient ale and beer recipes are the subject of another blog, not yet finished and not yet published.
The main point that I want to make in this post is that roasted toasted sprouted barley is not a suitable description of malt, malting or malting technology prior to the 17th/18th centuries AD. It's wrong. Archaeologists and archaeobotanists should read beyond their own literature. They should talk to maltsters and read about malting and brewing science if they want to understand what malt is, how it has been traditionally made and what its' properties are. It's a fascinating subject.
some further notes ...I've had some quiet, private and useful feedback from a few people. It seems that those who have no personal experience of making malt or brewing beer from the grain find it very difficult to understand these processes. Some struggle to see, in their mind's eye, how this so-called 'sprouted' barley can be transformed into ale. What happens to it? How is it processed?
I've been told that this film is helpful:
About 30 minutes long, it was made in Norway in the 1960s. The equipment used would have been available in the Viking and Medieval eras, probably also in the Iron Age. It shows some of the traditional, farmhouse brewing techniques. Also, it gives you an idea of how to handle the necessary quantities of grain that must be malted before being mashed and then fermented into ale.
There is great skill, knowledge and experience involved in making good malt and brewing ale with it. You can get all the sugars you need to ferment into beer from the grain. There is no need to add extra sugars or honey.
I hope it helps!