Yeast

July 14, 2012

Another defining ingredient in the bread is the kind of yeast, if any, that is chosen to raise the bread. The bread finds that can be dated back to the Viking Age in Scandinavia are generally unleavened, but a few of the breads or breadlike finds have either gas bubbles or in a rare occasion some possible remains of yeast. This seem to indicate that the common bread generally was unleavened. However, as a representation of the more southern traditions, where both ovens and and rye were more common these thoughts are aimed at the leavened breads of the Viking Age.

Looking at the conditions and finds one may recognise three fermentation methods that may have been used in Viking Age Scandinavia; spontaneous fermentation, sourdough and beer yeast.

This coincides quite well with the methods observed by Keyland in “Svensk allmogekost.” According to Keyland three methods of fermentation were traditionally used in Sweden prior to the 20th century, self fermentation, sourdough and beer yeast.

Self fermentation/self souring

The first method is described as the most original but also the most uncommon. Basically it is quite similar to the methods of making sourdough albeit without a starter. Wheatflour is mixed with water to make a thick dugh which is then left to stand for about a week. However at this point it was not considered fit for fermenting bread but to make some kind of weak beer. In order for the “dough” to be able to ferment a bread it had to undergo the process of brewing first.

A similar method is described by Olaus Magnus as being the way beer is brewed in Ethiopia. Wheat and barley are worked into a dough. It is left for ten days, during which some flour are added and the dough is kneaded. After ten days it is shaped into small breads, after which it is baked or perhaps rather dried. When it is time to set a beer the bread is broken into a pot containing malt. This description is quite close to the descriptions we have from ancient Egypt, where the connection between bakeries and breweries were very close.

A variety of this is described as partial self fermentation. This type of fermentation is described to have only taken 24 hours. The dough or flour is scalded with hot water or wort. It is then given a day during which flour is added and kneaded. The would certainly give some characteristics to the bread, and I could imagine that it would work well with a bread baked in a baking bell.

Sourdoughs

In contrast to the sourdoughs of today with an almost batter like consistency, the traditional sourdoughs in Scandinavia seem to have been more like a dough. Commonly sourdough seem to have referred to fermentation through remains of earlier batches of dough either through a conscious collection of doughremains from the trough or through such remains that may still be present in cracks and pores. Keyland gives a few examples of 19th century sourdoughs:

  1. The dough sticking to the trough is left there from one batch to the other and the yeast that survives will be used to raise the dough. In some traditions the bun or ball were cut with a cross on the top ( More exposed surface may have helped the fermentation). If the bun did not ferment properly it should be fed more flour. That is the sourdough is added to some luke warm water and some flour in the trough.

  2. Another common way to produce a sourdough would be to scrape of the dough from the trough and shape it into a small ball, which is left to dry in trough…when baking bread the ball is soften with luke warm water and flour and then mixed into the dough.

  3. Another rather straightforward way was to just keep a bit of the dough from the previous batch in a jar of flour. Since flour most likely were milled for each batch rather than for the whole season this may have been a less likely method.

It does make sense though that the sourdoughs were more or less made as a dough rather than a batter. In an era with a limited number of storage vessels for liquids which were not prone to lose some of the liquid, a batter may prove difficult to keep. Today, with glass jars and plastic containers battered sourdoughs are more practical.

Both selffermenting/souring and sourdough would acidify the dough, which in turn would alleviate baking a bread of rye.

Beeryeast / the dregs

Finally and perhaps most like the yeast today is the possibility to use the dregs or the forth of the yeast from brewing. The connection between baking and brewing were early apparent, perhaps most strikingly so in the breweries in ancient Egypt, where baking ad brewing went hand in hand. In a more European context this connection can be observed through the words of some puzzled Romans. When visiting the Iberian colonies, Pliny observed that the bread there was much lighter and fluffier than the bread back home even if it was not as white as the Roman breads. It is likely that the bread that he had encountered was fermented with the help of beer yeast as the Iberians at the time were well known for being good brewers.

In Scandinavia the use of brewing yeast was favoured during the from the 18th to the 19th century when it was replaced by the more modern baking yeast. However the connection between brewing and baking was probably well known even when we even if the biochemistry behind it was not known. In traditional descriptions we are told to take the dregs from the bottom of the beer vat when baking and as the beer is finished the remaining yeast was taken out or either stored as a liquid or as small dried buns, which are dissolved in the baking liquid when one should bake.

 What would have been the more likely method in the given context? Though most breads seem to have been unleavened at the time, it does not exclude the possibility that rye breads in the south at times were leavened. Exactly what method was used to leaven the bread is difficult to discern.

 The limitations in the Viking kitchen and the flour used would have influence how and what types of leavening were used. From finds we know that baking troughs of various sizes were used. However, containers for liquids that were protected against seepage were somewhat more limited: leather bags, staved vessels and waxed jars of pottery could all have been used but would not really have been fitting for a small amount of liquid sourdough. The lack of liquid sourdough in texts and descriptions from the 19th century makes it less likely that it were used as a leavening during the studied period. Considering, though, that the imagined bread is based on rye, the acidity of a sourdough is more or less essential.

 It is easy to imagine that the differing methods were used in a cycle of sorts, a cycle that most likely were distorted due to feasts and other occasions that influenced what bread were to be baked.

First, a self-fermenting dough were used in order to start the fermentation process, according to Keyland it was at this stage not powerful enough to be used for bread but needed rather

to be used in a low alcohol beer, “dricka”.

The dregs, or remaining yeast from the brew could then have been used either to start a new batch of stronger beer or to bake some bread. If used for a rye bread it were perhaps still left to self-ferment for sometime in order to increase the acidity.

A successful batch of the above dough would at this point (according to Keyland) be strong enough – have enough of the proper yeast – so that the remains in the trough could be gathered up, stored and used for the next batch of bread. Leaving it like this would also keep acidifying the dough making it even more suitable for making rye bread. When ever the fermentation went awry, due to mould, the wrong kind of yeast or if the yeast died the cycle would start over. Ofcourse this order would have been broken up in various ways. If one were baking for a large feast it would hve been likely that some ale yeast were added. If baking in a baking bell it would perhaps have been enough to just use a self-fermented dough

One should keep in mind though that most of the finds seem to indicate that the common bread was unleavened. This would have made the dough remains of the troughs bad starters and they would then need some kind of ale yeast to get started.

With the last thing in mind I would suggest that the bread in this exercise should be fermented using a dough that is left to self ferment but with an addition of yeast from a brew.

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Mead – tasting it

August 1, 2010

Though the plan was to end the fermentation quite early and try to achieve a nice sweet and somewhat alcoholic drink it proved more difficult than I first thought.

The mead that I had started brewing in two separate jars was only protected by a linen cloth, which I thought would be enough to keep most of the particles and dust away. After about a week and a half I decided to take care of both the mead jars, and proceeded to pour them into two different plastic bottles in order to keep the spicing apart. Before pouring the mead into a bottle I sieved it and tried to scope out most of the yeast that was floating. At this point the yeast seemed to be active in both jars. The two different batches had distinctly different smells, and also tastes. While the first bottle was still quite sweet one could notice an alcoholic undertone to it, the other however did not seem to be developing as quickly.

When I sieved the second batch of the mead, I received a small surprise as I found an unusually fat fly floating in the jar. After the first surprise and chock I decided to still keep this mead -minus the fly- to see how it develops. In a few early beer recipes it is describes how a crushed fresh rooster should be added to the batch. Are those just myths or would the proteins provide something?

As I finished the transfer to plastic bottles I brought them home to place them as cool as possible in order to stop the fermentation, however, the fridge was overfull and we experienced few comparatively warm days. Still as my room kept quite cool I hoped to be able to at least separate the mead from the yeast that had sunk to the bottom. However, after just two days the fermentation processes seemed to have continued at least in the first batch. As I opened the bottle a foam quickly raised and I had to close it again in order to not loose anything. This procedure quickly mixed the yeast, making any attempt to separate yeast and mead futile. I resealed the bottles as I had to rush of to my hearth for some other cooking attempts. After yet another few days, when I believed it to have been cooler I made a new attempt with almost the same result, except that now also the second batch (fly and caraway) had started to ferment in a similar manner.

Apparently the conditions for making any advanced trials when it comes to fermentation seems to be somewhat restricted at the moment, why I may continue this line of experiments once I have returned to Sweden. The samples of mead I made here was far to small to give opportunity to do any fargoing experiments. As I discussed in an earlier post I could either use cold -like a cold storing place, which makes summer a bad time of brewing- or heat to stop the fermentation. For heat I would imagine that one could make use of a hot stone to quickly heat the top of the brew and thus killing of the yeast. Another could perhaps be to add an infusion of the herbs one wants to spice the mead with. The boiling infusion would then kill the yeast in the top and after it has cooled down enough one may separate the dead yeast from the mead.

As one of my meads may be somewhat lessened by the addition of a fly I am still thinking that I should perhaps try the last method on this one. I could also try to stop the fermentation of that mead using a small amount of crushed lingonberries. These things will have to be done if time allows as I am now trying to get all parts of my participation of the local festival in order.

Finally the actual tasting, a few days ago circumstances allowed for a beer tasting, why I also brought out the first batch of the mead. It was still foaming quite a bit when I opened the battle and thus was rather fizzy. The colour was a somewhat cloudy and darker yellow, with a rather fresh smell of honey. The taste was still sweet, and did not feel to strong, but one could sense the alcohol beneath it all. While not very strong it had a nice balanced taste, with enough sweetness to make it a drink to sample rather than gorge.

Mead

July 14, 2010

As I already discussed under the post about sweetness honey would have been a fairly uncommon commodity not readily available to most, but rather something that would display exclusivity, luxurity and long range contacts. Honey as a product would most likely have been imported to Lofoten, and it seems fairly likely that on had to import honey or mead in order to satisfy the need also in the rest of Scandinavia. This would also mean that mead was drunk only at the most important of parties rather than as an everyday drink, and as such I believe that one would have been careful to not brew away all the sugars from the honey.

This notion is supported in the ever untrustworthy Olaus Magnus who among his mead recipes mentions two things that may indicate such a practice. Instead of the contemporary moth to ferment the mead, Olaus Magnus states that one week is enough, which would yield a beverage that is less strong than the meads generally produced today. Secondly and perhaps more important is the advice from Olaus Magnus that one should balance the sweetness with either gale or hops.

Despite it being rather unpedagogic, in the context of this museum to brew a mead, I still decided to do so, mainly because I wanted to try out some more thoughts about fermentation. The process of making mead is quite simple in theory; dissolve the honey in hot water, add either some herbs or a infusion of the herbs wanted, let it cool down, add some yeast and then wait for it to transform the sugar into alcohol.

Though not really following any particular recipe, I chose to still follow the relation between honey and water as given in one of the descriptions given by Olaus Magnus, resulting in me using about 2 jars of honey to two jugs of water or to be a bit more metric, 800 grams of honey to 3,5 liters of water. The water was brought to a boil and I tried to get most of the honey out of the jars. After adding the honey to the soapstone vessel, I let it boil briefly while skimming it, I guess that this step is rather unnecessary in present day mead making as it probably aims at removing any surplus proteins. After I skimmed it I let it simmer for a while in order to dissolve all of the honey. After it then had cooled down enough to be handled I proceeded to pour it quite evenly into two of the tyttinger jugs I had been using before. To one of the cans I added a hand full of crushed juniper berries and in the other some caraway seeds. Part of the experiment was to see if the pores of the jug would have contained enough yeast to provide a good start for fermenting the mead. Halfway through the process of preparing the mead, I realised that the jugs were glazed on the inside and therefore without any suitable pores. I would therefore have to add some yeast to the brew. Instead of using the bought yeast as last time, I planned to use the yeasty remains from the last brew. However, at the time I had to finish for the day the liquid was still to hot to add any yeast. The brew should then be fermenting for about one week, at least according to the earliest known recipes.

The use of yeast raises some interesting questions, would one have been aware of yeast as we know it and save it from batch to batch or was it considered something completely magical? In Scandinavian and Anglo- Saxon languages the terms of Bearma and Dreg signifies two different stages of yeast, and as these terms seem to date back to the Iron Age it is quite possible that yeast was not an unknown entity, even if the micro-biology behind it was. A few days ago I talked to a microbiologists who commented on the possibility to get yeast from different plants. Apparently different plants would have differing affinities with yeast. The most well known examples would be grapes and apples upon which a very benevolent yeast is gathered. Less useful for yeast would probably lingonberries or cranberries be as they are quite sterile in themselves. If there is a difference in how yeasts grows and gathers on the plants mainly used when brewing – meadowsweet, juniper, yarrow or gale – there might also be a possibility that some of these plants were used not only for taste but also for a good addition of yeast.

On a final note about mead and the use of honey in mead, as I am not at the moment completely clear on how to stop the brew after about a week, if the brew proves to still be sweet at the time. The to main methods I can think of would be through either heat or cold. To warm and the yeast will die, but it would also cause the alcohol to steam off, to cold and the yeast will grow tired. Either way it should be possible to separate the brew from the dead or sleepy yeast in the bottom. Another way would be to add some herbs or fruits that would stop the fermentation, here lingon berries comes to mind.

Still, all in all, honey and mead would have been quite expensive and required more of the chieftain than just faraway contacts. Another and not really considered solution to keep up an expected duty to serve mead at a feast without being brought to the brink of poverty, would be by brewing a mölska instead. Mölska is a Swedish name for a beer that was refermented with the use of honey. Such a beer could provide not only strength and sweetness required but would also have the revealing honey aroma. This would have been a far more economical solution here at the fringe of the world.

Update: Looked into the jars today, a day after adding yeast to them, and could see the mead being topped by a healthy froth

Update II: The froth has calmed down a bit but it seem to still be working, one could even hear a fizzing sound from inside the jars. Today almost six  days after starting the batch I tasted a small sample. Quite clear in colour, still very sweet and honey tasting, but with a slight alcoholic taste hiding in the background.

Beer IIb

July 6, 2010

I checked on the beer a few days later, Nothing had really happened with the the first batch except that it looked quite cloudy by the added yeast, but no real activity. The second batch on the other hand displayed some bubbles on the surface – mould or budding fermentation? I’ll leave it for a few more days to see what way it goes. In order to make any eventual yeast feel more comfortable I moved both jugs into the guide room, where it always is far to warm and cosy for me. However, a tourist made a comment the other day, about yeast in some of the plants we display at the museum that may be connected to beer brewing- yarrow and meadowsweet. He or she said something about them carrying yeast. Is there anyone of my readers who have some more ideas on yeast-carrying plants, which plants would be more suited to hold enough yeast? This ought to be looked into with some more care.