I have a new project I'll be announcing soon, but first: I mentioned a while ago that the BBC programme QI, former hosted by Stephen Fry and now by Sandi Toksvig, will be featuring my bog butter experiment on the show. With that in mind, I thought I'd rewrite and extend this piece a bit.
When most people picture Ireland, they picture green fields
and old stone walls, and that’s true of some places. Ireland also has lots of
bog, though – the Bog of Allen, where we live, stretches almost a thousand square
kilometres across several counties. Bogs are difficult to get through – they have
few roads or villages even today – so they could be isolated, mysterious places,
where characters in folktales met giants and fairies, a place where a starving
and subjugated people could hide, or hide things.
A bog is a natural wetland, like a swamp or marsh – the difference
is that the water is very acidic, so most kinds of plants can’t grow there –
but peat moss does very well. Vast areas get covered in peat moss, and as
layers of moss die off new layers grow over them, so you get gradually
thickening layers of organic matter. In most circumstances it would just decay
and become soil, like most things that die – but it’s soaking in dark, acidic
water where fungi, insects, even most bacteria can’t survive, so it doesn’t
decompose.
Over thousands of years it gets squeezed into a dark red solid
called peat, or “turf” here in Ireland. For centuries this was the main fuel
here, and kept many a potato farmer warm on a chill evening. That’s why this
canal was built in the 1700s – turf was strip-mined from the bog, dried, loaded
on carts, pulled by donkeys on these rails, and loaded here on barges to be
brought to warm the houses of Dublin. The history and future of turf as a
source of energy deserves its own video, but the point here is: Dead things buried
in the bog don’t rot, so it’s an ideal place to store things.
People around here still fish out trees that fell in
centuries ago and carve their wood into ornaments; the bog-water stained the
wood almost black, but it’s still wood. Turf-cutters here find human bodies
sacrificed by Druids thousands of years ago, their skins blackened and cured
like leather but with their faces still recognisable. This might have been the
inspiration for the dead marshes in Lord of the Rings, where you could still
see the bodies of the dead under the water.
So people dig up many things from the past in the bog and
meant to come back for -- necklaces, coins, tools, swords, 1,200-year-old
prayer-books. And sometimes they find stores of food, up to 3,000 years old and
not only intact, but edible. Specifically, they find butter.
Bizarre as that sounds, more than 430 caches of butter have
been found in the bog, some small as fists, some big as barrels. The aforementioned
3,000-year-old butter weighed more than 35 kilos, the size of a child. And many
of the apparently very adventurers discoverers any such discoveries have been
eaten, and were reported to be delicious.
This doesn’t even count all the buried gastronomic treasure
still waiting out there. Since we can suppose that people buried their butter
to unearth and eat it later, and usually did so, these hundreds of finds must
represent the small proportion of times that their owners died or the locations
forgotten. This must have been a rather commonplace activity.
So why butter, you ask? A surprising number of foods around
the world are preserved by being buried in the ground, but they are usually
dried foods in arid climates (cheese in Italy), or sub-Arctic countries where
the ground is freezing (salmon in Sweden), or where the food is meant to
ferment in some way (eggs in China). In this case it’s waterlogged ground, it
would probably disintegrate in the water over time unless it’s naturally waterproof,
like fat.
This might have been done with meat as well; Archaeologist
Daniel C. Fisher buried various meats in a frozen pond and a peat bog for
comparison, and found that after a year, the meat buried in the bog had no more
bacteria than the frozen meat. If this sounds gross, keep in mind that
fast-food burger you last ate might have been more than a year old.
Also, butter makes a valuable and high-calorie food for poor
agrarian people; with it you can fry food or preserve things like potted meats.
It was also taxed in medieval times, so burying it could have been a kind of
tax evasion.
The constantly-cold Irish bog would keep the butter solid, and it would only age like cheese; in fact, the one taste-tested by Irish schoolchildren was said to taste like well-aged cheese. Some people might simply have liked the taste.
The constantly-cold Irish bog would keep the butter solid, and it would only age like cheese; in fact, the one taste-tested by Irish schoolchildren was said to taste like well-aged cheese. Some people might simply have liked the taste.
I like to experiment with old ways of preserving food; I
learned how to preserve fruit over winter, how to preserve eggs in lime-water
or isinglass, how to pickle vegetables or learn which mushrooms are edible. But
in all those things I had people around to show me; lots of my older neighbours
still make their own jam or wine. I don’t know of anyone who’s ever tried this
who could show me how. Thankfully, it’s pretty straightforward – all you need
is to access to one of the world’s peat bogs, and I happen to live in the
middle of one.
My daughter and I made some butter at home, which anyone can
do; you just pour milk and cream into a jar, put on some music and start
shaking. We couldn’t fill it more than a quarter full or we would just get
whipped cream, so we had to do this many times to get the three pounds . At
some point the sound of the sloshing changes, and you get a solid clump of
butter in the middle of the liquid. Traditionally Irish housewives would pat
the butter dry of its remaining liquids, but we simply clarified it.
Then we
froze it to keep it solid, wrapped it in cheesecloth and a rope, walked about
ten minutes from our house into the bog. I paced the steps first in one
direction and then another to make sure I would remember the spot, and tied the
rope to a nearby tree to I could find it again.
Seventeen months later we dug up the butter, and while the
picture looks pretty disgusting, once we washed it off and unwrapped it the
butter looked much the same – a little darker yellow and with an earthy smell,
but not rancid.
The taste was similar – recognizably butter, with a slightly
earthy, cheesy flavour a bit like parmesan; it was particularly good over
popcorn. It wasn’t something most modern people would choose to eat regularly,
but for people who faced periodic famines, it was an ideal store for lean
times.
Of course, this butter was only in the bog for 17 months,
and the effects are probably very different over 3,000 years. So I’m burying
more butter for a longer period of time – dozens of kilos -- and planning to unearth
it in about three to five years, some further down the road. If anyone wants to
buy some in advance, you can be one of the few people in the world who can say
they had this ancient food.