Friday 30 June 2017

On the origins of beer

In Pete Brown's latest book there's an intriguing passage about brewing with unmalted grains. The problem with brewing with unmalted grains is they don't have the enzymes that will break their starch down to fermentable sugars. This is something often overlooked by people researching pre-historic beer who, mistakenly in my view, think that wet grains will spontaneously transform into beer.
"He shows me the results of experiments that prove you can still get fermentable extract from unmalted grains. Malting yields by far the most fermentable extract, but Martin brewed with raw grain, crushed grain, cooked grain and crushed and cooked grain. Malted grain gave a beer of 6 per cent ABV, but the unmalted, crushed and cooked grain yielded a beer of 3 per cent ABV, and there were traces of fermentation in all the brews."
As I mentioned this was one of areas I'd like to see more about Pete was kind enough to let me know more information could be found in the book Liquid Bread, so I had to get a copy.


It's actually an anthropology book which is interesting, as it's a change in perspective about beer compared to what I normally read. The relevant passage in the book is sadly brief, referring to another study:

"Extensive preliminary trials showed that high alcohol yield is possible only with malt. Most fermentations on unmalted grain had no appreciable alcohol yields. Boiled, therefore gelatinised, unmalted barley grist was the only one having a small yield, comparable to half the alcoholic content when using malt grist"*
Even with Sci-Hub I couldn't get hold of the paper about the preliminary trials so there could well still be some fascinating facts that need tracking down. How the starch breakdown occurs with the unmalted grains we're not told, but it can't be from enzymes in the grains as they've been boiled. The boiling will gelatinise the starch though.

The authors continue saying how they made their beer using malted grains, but with a low temperature mash and a mixed culture fermentation:

  • mashing at 34°C, with 15 minutes of vigorous mixing and a very wet mash (liquor to grist ratio 1:8.3). 
  • Inoculated with a mixed culture of Saccharomyces and Schizosaccharomyces yeasts and Lactobacillus spp. added to the mash. 
  • Final attenuation was 87 percent but due to the vary dilute mash ABV was just 1.6%.
Perhaps the mixed culture is able to carry out a partial breakdown of the starch in the boiled, unmalted grains in a manner reminiscent of how sake is made?

We're still however left with a situation where grains need to be either malted or cooked before anything like beer can be made. So beer remains something that cannot occur naturally or accidentally, as something like wine or mead could. From what I've read beer seems to have emerged around the same time as bread, and both are human inventions.







*Zarnkow, M. et al. (2006) Interdiziplinäre Untersuchungen zum altorientalischen Bierbraune in der Siedlung von Tall Bazi/Nordsyrien vor rund 3200 Jahren. Technikgeschichte 73 (1): 3-25. 

18 comments:

  1. Lars Garshol was talking about brewing with 100% raw grain. Mashing and then boiling the mash. Maybe there where some microorganisms in the domesticated yeast slurry that where starch converters (like koji in japan). I mean if you throw a mixed culture long enough at a starchy liquid they will evolve to a certain degree.

    Cheers
    Benedikt

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    1. I can see something like that working, but obviously it has a boiling stage.

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  2. One thing I've been thinking is that the working assumption is that the drink needed to be all grain beer. If you go back only a few centuries fields would have been sown with blends of grains. I wonder if blends of various fermentables might have been brewed, too. Perhaps the enzymes were provided by a different material than malt.

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    1. Yes, if you go back far enough fruit/grain/honey/whatever seem to have been used together which could have some interesting results.

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  3. Isn't it possible that unmalted grains left to soak in the water would eventually germinate, at least partially? Like lentils or beans left in a humid environment for too long. Then saccs would take care of the sugars fermentations and some wild yeast could even ferment some starches.

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    1. I can certainly see green malt being made accidentally like that, but I still think that if it was left longer it would just go mouldy.

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    2. This is all very interesting to me. Who were the first maltsters? Last year I went to a meeting/seminar with maltsters and brewers at the Highland Park Distillery (part of the Orkney Science Festival). They explained that grain is a living thing, that it will drown if left in a bucket of water. Grain needs both water and oxygen to begin the germination process. It must have air rests. The steep tanks at the Maltings do this, the water is drained at regular intervals and the steeped grain is left to aerate for several hours before fresh water is added. This effectively imitates the traditional technique of leaving grain in a bag in a stream. I wrote up this malting seminar, it's on my ancient malt and ale page "a morning with maltsters". Long time ago I read the malting section in Bewley and Black's book "Seeds:physiology of development and germination" and they say the same thing. Oxygen and water.They explain the biochemistry and physiology behind it too. Fascinating stuff. germination.

      The 'grain was left in a bucket' theory does not work.

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    3. I've never tried malting with continuous steeping, but hving air rests in steeping really only dates from the 1950s. I'd better have a look at Stopes...

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    4. The steeping part with air rests is just the the imbibification, where the grain takes up sufficient water to begin the germination process. When the maltster judges the grain to be wet enough, it is turned out onto the malting floor. Or, if you are a Norwegian farmhouse maltster, onto a wooden tray in the malt house. Lars Garshol's work has uncovered the traditional ways of doing these things and they probably go back thousands of years. The ethnography, if you like to call it that, but I prefer traditional and probably ancient.

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    5. https://brewingbeerthehardway.wordpress.com/2017/02/12/un-aerated-steeping-part-1/

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  4. My theory is that at least somewhere, at some point (because beer isn't like the light bulb that someone invented and then it spread, it will have to have been "invented" at different times and places by different peoples) someone was cooking a porridge of crushed grain flavoured with berries and/or honey and/or whatever else they had at hand, forgot about it and either the yeast in the fruit started to ferment or maybe fruit flies brought them.

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    1. I agree, some sort of porridge seems a more plausible starting point to me. And if the grains were malted it wouldn't even need to have been boiled.

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    2. Just got me thinking. It's become quite trendy among the "healthy" food crowd to let lentils and other things germinate for some time before eating. I wonder if early agricultural peoples did something like that, and then cooked the stuff

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    3. Yes, I can well see early malting arising. Green malt is not a million miles away from bean sprouts, and is much more paletable than unmalted grains.

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    4. I reckon the malt sugars came first, before either bread or beer. Around twelve thousand years ago people discovered that partially germinated grain would make something sweet when gently heated with water. You have to make the sugars before you can make the ale or beer. Malted grain can supply all the necessary sugars for alcoholic fermentation, you don't need to add fruit or honey.

      There is some interesting archaeological evidence of early grain processing at a site near Lake Galilee, Ohalo II, c23,000 years ago, where they may have been making some sweet barley cakes/bread/bappir from malted grain. However, it is hard to know for sure.

      More substantial archaeological evidence is that they were making malt on the smooth, level earthen, clay or lime plaster floors at the earliest agricultural settlements in the Fertile Crescent around ten to twelve thousand years ago. Malting floors are for large scale production. So they must have worked out how to partially germinate grain and make fermentable malt sugars before then.

      I did some experimental archaeology, making sugars from crushed malted barley on a hot stone by the fire (as a sort of cake of biscuit) and I've also have mashed successfully in a simple earthenware bowl.

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    5. Interesting stuff Merryn, I knew this would be up your street!

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    6. It's making the the malt that interests me most. Specialist malts are, as you know, a recent thing (roasting and toasting are c300 years old, Industrial Revolution etc) but the knowledge of how to make base malt has been around for thousands of years, since the so called Neolithic Revolution.

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