Vikings brought freeze-dried cod to Germany


Well-Known Member
Oct 1, 2017
Apparently, the Vikings discovered how to freeze-dry sea fish - which made it easy for them to transport them to settlements around Europe
Noted especially because of how we underestimate both the ingenuity and trade links of those humans who went before us. :)
The last line is very true, but I have an elaboration and a correction that may interest you.

The concept of air-drying certain fish (i.e. non-oily ones), had been known for millennia. Likely, too, the use of lye (derived from potash). The word for the resulting air dried and lye-treated food is lutefisk (lyefish) -- in Finnish lipeäkala and, more humorously, saippuakala (literally, 'soap fish'). I have researched the Neolithic, and this method of preservation seems wholly defensible then. I have also studied the Vikings to a certain degree, and found that, b/c of their stocking up for brutal winters, they were well aware of the provisions needed for maritime excursions. (They had a knowledge that southerners did not, for a change. Otherwise, the northerners were rather backwards. E.g. the Iron Age came much later for them.)

I suspect the article is what you will see when a journalist, undereducated in science, writes about science. As someone well educated in science, I notice this sort of reporting often.
Freeze drying involves the sublimation of water under a vacuum. This technology was not available to the Vikings. Water does not readily sublime at atmospheric pressure, though I grant it could have occurred, in part and very slowly -- much like what we now see in our freezers, when we leave food in a sealed bag for a long time. Note that some, but not most, of the water in frozen food can accumulate as snowy-ice. This process is a largely incomplete version of, say, making freeze-dried coffee -- where the water is wholly removed.

In sum, the Vikings built on their ancestors knowledge with their own advancements, yes, but not in food preparation (at least as far as I have found).