Topic Ancient British Ale
Recreating ancient ale using burnt mounds
David Chapman found an eroding “burnt mound” – a common but unexplained prehistoric mound of fired stones – on the Lleyn peninsula at Hell’s Mouth. Excavations in 2008 revealed an oak trough containing a residue of burnt stones and charred chaff and seeds (News, Mar/Apr 2009). Last summer Chapman and a team from Ancient Arts tested the theory that the trough had been used for brewing. The result was a lot of burnt stone – and 77 pints of light ale.
That burnt mounds had been used for brewing was first suggested by Billy Quinn and Declan Moore, who made an ale using fired rocks in a wooden trough in Co Galway. Chapman set out to replicate the process and compare the resultant debris with that excavated at Hell’s Mouth.
A trough a quarter of the original’s volume, set into a pit and sealed with clay, was filled with water and the area around saturated to stem any leakage. A bonfire of small round wood was lit over a heap of stones, and in a hot, bright and oxidising blaze a strong colour change was noted in the stones as they turned “white” as their temperature rose to red hot.
The stones were raked from the ashes, dropped into the trough and returned to the fire. This way the water was boiled to sterilise it, and all buckets and equipment were “scalded”. Brewer’s malted barley was drenched in boiling water to help release the starches, and then added to the trough after it had cooled to 60°C. The resultant “wort” was held at 60°C for an hour and a half with the addition of a hot stone every 10 minutes.
Elderberries were added – the skin being one of the best sources of wild yeast in Europe – with a small quantity of brewer’s yeast as a backup. The ale was further flavoured with honey, blackberries and rosehips. Once strained through cloth into buckets, the wort was cooled in a stream and then covered and left to ferment for five days. The mash was cooked on the hot stones into bread or biscuits, which Chapman describes as “tasty and nutritious”. This left some of the stones covered in charred barley.
As they worked, says Chapman, the stones began to form “the classic horseshoe shape that is so common in burnt mounds”. The many stones at the mound centre were needed to bring a large volume of water to the boil, but to hold it at a constant temperature it was easier to use stones from either end of the very hot fire. In the nature of the process it is unlikely, he adds, that proper stratigraphy would be forming, so mounds used over many years could appear to indicate a single event.
Original article:
Jan/Feb 2010
Edited by Mike Pitts
Ancientfoods 