Ancient Steinbier--Irish Edition

This is very cool:
Moore is taking me to visit an unexcavated fulacht fiadh (pronounced FULL-ahk FEE-add), or fulachtaí fia in plural, the most common type of prehistoric archaeological site in Ireland. Better known as a “burnt mound” in the neighboring United Kingdom, where they are also found, there are nearly 6,000 recorded fulacht fiadh sites dotted around Ireland alone...  Although commonplace and easy to identify, the fulacht fiadh remains enigmatic. There is no consensus among archaeologists about what they were primarily used for. Various theories—such as cooking, textile production, bathing, and Moore’s personal hypothesis, a type of ancient microbrewery—have all been proposed.
Photo: Declan Moore and Billy Quinn
When we arrive at the site, Moore shows me the basic features of a fulacht fiadh—a horseshoe-shaped mound of soil and rocks surrounding a depression big enough to park a small car in. Surrounding the troughs are U-shaped mounds made of stones. These mounds can reach heights of more than six and a half feet, though on average they are roughly three feet high, and made of sandstone or limestone. Neither rock type is typically found close to fulacht fiadh sites, indicating that the Bronze Age Irish chose the stones deliberately.
According to Dennehy, the mounds likely cover hearths where the stones, which show evidence of heat-cracking, were fired. The cracking also provides strong evidence that after being heated, the rocks would be placed in the troughs to heat water. “The stones that were heated and shattered during this process were discarded nearby,” Dennehy explains, “gradually accumulating to form the mound surrounding the trough.”

The article then describes how the archaeologists did a bit of applied study and brewed up a batch of stone gruit ale.
Using malted barley donated by a local brewer, they stirred it into the hot water. After 45 minutes, the grains were converted to a sugar syrup called wort, which was transferred into special replicas of Bronze Age pots. Yeast was then added, as were elderflower, juniper berries, and yarrow for flavoring, and the brew was left to ferment for three days. (Moore and Quinn note that windblown yeast would have triggered natural fermentation for Bronze Age brewers.)  Moore and Quinn converted nearly 80 gallons of water into 30 gallons of ale that was copper in color and had a smoky flavor.
Much as is the case with the Marryn Dineley's hypothesis about neolithic brewing in Skara Brae on Orkney Island, the Irish example has dissenters:
Members of the Irish Archaeobotany Discussion Group, however, expressed doubt in Moore and Quinn’s theory, again pointing to a lack of accompanying evidence at fulacht fiadh sites. “Such large-scale processing of cereals would leave a regular trace in the archaeological record, perhaps in the form of uncharred, malted grains at waterlogged sites,” the group wrote in a letter responding to the Archaeology Ireland article.  
I have no dog in the race, except that I like the idea of neolithic brewing and see nothing especially implausible about it.  Some archaeologists have argued that beer started with "gruel beer," a proto state where wetted, crushed grain reaches mild fermentation.  From this, eventually, people learned to use sprouted grain and then figure out malting.  The "eventually" is key.  Humans even of the distant vintage we're talking about were clever.  Had they come across gruel beer, it's hard to imagine that in the span of years or decades they wouldn't have figured it out.  So really, all you need to look for is gruel beer to hypothesize that real beer wasn't far--in archaeological terms--behind.

And anyway, it's more romantic to think of beer's roots delving ever further back into human history.