The Raisins Experiment

Thus far, we have been comparing our mead recipe to another entitled “A True Viking-Style Mead" by Your Shout, Mate (2012). As we mentioned before, while we were unable to meet all of the requirements exactly (due to lack of access to traditional materials and resources), we decided to test the claim that raisins were used by the Vikings to gauge when the mead was complete, even though this aspect was not listed elsewhere. Due to time limitations, this experiment was conducted by one group member (myself). I soon learned that we took a chance by trusting the recipe from a blogger, and that the nature of our short mead as well as use of champagne yeast complicated the results.  
 
The raisin experiment was both a successful and unsuccessful endeavor. This could be attributed to multiple factors. Firstly, based on the blog post's sources, it appears that the blogger incorporated this element into the recipe based on recipes for Sima (a type of Finnish mead), though many recipes for Sima today use sugar instead of honey (Diehl 2013; Your Shout, Mate 2012). Raisins are typically added during the second stage of fermentation along with sugar (Acquiring taste 2012; Diehl 2013; Food Fusion in Finland 2011; Your Shout, Mate 2012). According to multiple sources, the end result is carbonated (Acquiring taste 2012; Diehl 2013; Food Fusion in Finland 2011). The raisins therefore work to indicate when the batch of Sima is ready to drink, by taking in carbon dioxide and subsequently floating to the top (Acquiring taste 2012; Diehl 2013; Food Fusion in Finland 2011). As Your Shout, Mate (2012) did not review the purpose of the raisins in detail, our group interpreted their use as a measurement of fermentation. 
 
The above information was learned after attempting this experiment which I will now cover. As the steps we used to make our short mead have already been reviewed in multiple blog posts (see "First Batch of Mead" and "Unpasteurized Mead Experiment"), I will not repeat them here. The only alterations were that the must left over from the honeycomb experiment was incorporated in addition to a must made from pasteurized honey (as it was already available in my home), and a glass carboy and decanter were used instead of a bucket and towel. I used Thompson Seedless Raisins (by Safeway Kitchens), though the exact type of raisins to use were not listed on Your Shout, Mate’s (2012) blog. Since I had access to a hydrometer at this time, I measured the initial gravity reading, which was above the highest reading (1.160/over 21%) and therefore could not be recorded. I suspect that the addition of the honeycomb must may have impacted the reading, as it had been sitting for a while and probably cooled off. According to the instructions, when the mixture is below 60° F you are supposed to subtract from the reading. For instance, if the mixture is at 50° F, you subtract 0.0013 from the gravity reading. I did not have a device for measuring temperature on hand, so I was unable to determine the exact alcoholic content later on.
 
As there is only one stage of fermentation for short mead, I added in 25 raisins (which is the number recommended in Your Shout, Mate's (2012) recipe) in before the yeast. Approximately half an hour later, all of the raisins had floated to the top, and I was left wondering what I had done wrong…until I considered the yeast. For each batch of mead, we have been using a yeast called Saccharomyces cerevisiae, which commonly referred to as a champagne yeast and is used to make sparkling wine. This likely affected the experiment since sparkling wines are by nature carbonated, not to mention the process of fermentation produces carbon dioxide, and this reaction is most evident during the initial stage after the adding the yeast (Slinkard 2013). Compared to Sima, which some recipes say incorporates a ¼ tsp of (unspecified) yeast per gallon or 3.78541 litres (Diehl 2013), the packaged yeast we used provided about 7x this amount for only 3 litres of must. Your Shout, Mate (2012) did suggest the use of Finnish Baker’s Yeast, which is also used to make bread and may have been used by the Vikings; however, we were unable to find this yeast locally, which is why we chose champagne yeast. Thus, the ratio of yeast to must as well as the type of yeast used impacted the results of this experiment. 
 
To see if anything changed over time, I removed the raisins and added 25 fresh ones four days later. The gravity of the mixture at this time was 1.070/9.3%, so the alcoholic content had likely increased, but this cannot be confirmed as temperature was not controlled for. Again, the raisins began to float to the top within half an hour, but interestingly they did not stay there. Until the next morning, the raisins continued to float up and down. 
 

 

While I am unsure of the exact reason for this, I wonder if the alcoholic content had something to do with it. It would be interesting to test this experiment over a longer period of time to see how the raisins respond as the alcoholic content increases and the initial period of fermentation settles down. Perhaps with time (and a different yeast), the raisins would fail to float to the top or take much longer, and could therefore work as tool to gauge the fermentation process. While this is beyond the scope of this project, I was at least left with a lovely batch of mead and a lot to think about!

 

- Jo

Bibliography

 

Diehl, K., 2013, Finnish Spring Mead (Sima). About.com [Online]. Available: http://scandinavianfood.about.com/od/beverages/r/SpringMead.htm

 

Slinkard, S., 2013, Wine Fermentation. About.com [Online]. Available: http://wine.about.com/od/vineyardvocab/g/Wine-Fermentation.htm

 

Unknown, 01/01/2012, A True Viking-Style Mead (Mjöð), Your Shout, Mate. Available: http://yourshoutmate.blogspot.ca/2012/01/truevikingsytlemeadmjo.html [Oct 9, 2013].

 

Unknown, 04/24/2011, Sima (Finish mead for Vappu/May Day), Food Fusion in Finland. Available: http://foodfusionfinland.blogspot.ca/2011/04/sima-finnish-mead-for-vappumay-day.html [November 14, 2013]. 

 

Unknown, 03/02/2013, Sima – Traditional Finnish lemon mead, Acquiring taste. Available: http://karaimame.wordpress.com/2012/05/01/sima-traditional-finnish-lemon-mead/  [November 14, 2013].