Experiment II Flaxseed oil

Several plants with fatty seeds has been grown in Scandinavia prior to the medieval period and it is possible that seeds from flax, hemp, rapeseed and gold-of-pleasure (Camellina sativa) as well as hazelnuts could have been used for oil which in turn could have been used both for cooking and for various crafts. From historical sources we know that rapeseed oil was in use in Holland at least in the early 16^th century and that recipes for making walnut oil and almond oil can be found in danish cookbook from the 13^th century. In Eketorp a site that was in use both during the late Iron Age and through the medieval period a small “cake” consisting of seeds from both flax and gold-of-pleasure was found and later analysed.

 

However, less is known of how the oil was actually manufactured during the Viking Age. In this experiment I aim to try to make flaxseed oil using the methods and material that may have been available at the time.

 

Method I: This one is inspired from a 13^th century recipe for walnut oil. In the original recipe the nuts are placed in a heated mortar and then the oil is wrought through a cloth. As stone or metal mortars are lacking, and I can not get hold of a soapstone vessel, I intend to crush the seeds into a paste with a heated stone on a saddle quern and then wring out the oil through a wollen cloth if available (Woollen cloth rather than linen was used in the flax oil industries as they will absorb less oil, I guess). In order to get a better force in the wringing I would like to fasten one end to the wall/ a tree or something else firm and in the other end use a branch to help me wring it.

Problems: The cloth will still absorb quite a lot of oil, and will I be able to get the oil out of the cloth. Another potential problem lies in the durability of the cloth – will it hold? Finally is ofcourse the question if we will be able to extract any oil at all?

 

Method II: This one is inspired from later industrial production of flax seed oil. First I’ll bruise and crack the seeds on the saddle quern and then pack them into a bundle, again in a woollen cloth. The bundle will be put in a mansized wooden mortar.[ Though no finds of them survives, there are some large wooden artefacts that may have been used as pestles.] Repeated beating with the pestle may give the same result as pressing the seeds.

Problem: The main problem with this method is of course if the mortar will absorb most of the oil. In actual use the mortar would probably be saturated from everything that has been pounded in it – to properly simulate a well used mortar I could perhaps try to soak it in some other oil before we start the process.

 

Method III: Crush & boil. In this trial I’ll first crush the seeds and then pour the paste into boiling water and let them boil with it so that the oil collects on the surface. The the oil is skimmed of or decanted. This method however seem to have no connection with traditional ways of making oil as far as I could find.

Problem: I am not sure that I can achieve that with the available material.

 

Now oil extraction lies a bit outside my expertise, so any input on making traditional oils or methods of pressing seeds in pre-historic Scandinavia is welcome.

Experimental weekend: cooking pits

At an event at Ekehagen next week I am going to conduct two experiments in an Iron Age/Viking Age context. So in preparation for those I’d guess I try to write down some of my thoughts for the blog.

 

Experiment I Cooking pits.

Cookingpits have most likely been used in Scandinavia, from the Stone Age up until the Viking Age. What has been interpreted as possible cooking pits has be found at several Viking Age sites, these pits are about 1-2 metres across and are usually filled with fire cracked stones. Cooking pits are mentioned the Edda by Snorri so it is likely that the idea of them where present during the Viking Age. However, the interpretations do differ on how the pits where used and how the meat in them was prepared.

 

Trial I: Packaging the meat.

 

In the open air museums in Scandinavia most displays of cooking pits are made with inspiration from the cooking pits used in the Pacific ocean and pieces of meat are clad in leaves and birch bark, or one adopt to the regulations of the health department and use tin foil instead.

 

As the pits have a diameter from one to two metres across, I would suggest that the pits were not mainly used for chunks of meat but for whole animals. In order to keep them from burning and drying out, the animals were cooked with their skin still on. This practice was, according to some sources, used in the Balkans in the 19^th century.

 

The experiment: To see if we can get a good result of the meat using just the skin to protect the meat from the heated stones. Is it a doable method and will this method still provide a good and juicy meat?

 

Trial II: Norwegian vs south Scandinavian cookingpits.

 

The basic principle of the cooking pit is that stones are heated and then the food that should be cooked is buried with the stones which will retain the heat for a long time. Though the prinicple is rather simple differing methods has been suggested based on the observations of cooking pits in Northern Norway and in the South of Scandinavia.

 

In the north the pits are suggested to first be packed with wood and on top of that a layer of stones are packed. As the wood burns under the stones they will be heated and when the wood is all burnt away the pit should be ready to cook the food. The advantage of this method is that there will be no carbonised wood on top of the stones that might cause cold spots when cooking.

 

In the south, instead, it has been suggested that the stones are packed in the bottom of the it and the wood burnt on top of the stones. The great advantage of this method is that t is easier to reuse, and that the readier access to oxygen will make this fire buring more fiercly.

 

The experiment: I will make two pits, one with each method, and as the wood has burnt out compare the temperature and the time it would take for the pit to reach an acceptable temperature.

In each pit a piece of meat that is packed the same way will be added and the pit closed. When the mat is believed to be finished it will be taken out and temperatures compared between the meat that has been cooked in each pit. If possible both pits ought to be excavated at a later point in order to compare them to the looks pits assumed to be cooking pits from a Viking Age context.

Yeast

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 20^th 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 19^th 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 18^th to the 19^th 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 19^th 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.