Why 31 gallons?

[Moonlight]

A recent post has me again wondering...does anyone know the history behind why the American beer barrel is 31 gallons?
The UK ale barrel has legally been 36 (Imperial) gallons for many hundred years, but was supplemented with 30 gallon "Beer" barrels for hopped beer when it was introduced in about 1400 AD from the Continent, and later 34 gallon barrels were briefly required for intermediate strength beer in the 1700's.

[mic_mac]

I know it's odd (and a little funny too, as Merkins have a stereotypical reputation for going around the world saying "oh sure we have one of those, only bigger!")

Please don't flame me - I've liked most of the Americans I've met!

But your pints are smaller too (473ml v 568ml - c.20% bigger)

I should have a book or two somewhere that might suggest why - I'll try & hunt it out.
cheers
MikeMcG

[GlacierBrewing]

A recent post has me again wondering...does anyone know the history behind why the American beer barrel is 31 gallons?
The UK ale barrel has legally been 36 (Imperial) gallons for many hundred years, but was supplemented with 30 gallon "Beer" barrels for hopped beer when it was introduced in about 1400 AD from the Continent, and later 34 gallon barrels were briefly required for intermediate strength beer in the 1700's.

hmmm...
this is what I've found....so far:

"barrel (bbl or brl or bl) [1]
a commercial unit of volume used to measure liquids such as beer and wine. The official U. S. definition of the barrel is 31.5 gallons, which is about 4.211 cubic feet or 119.24 liters. This unit is the same as the traditional British wine barrel. In Britain the barrel is now defined to be 36 Imperial gallons, which is substantially larger: about 5.780 cubic feet or 163.66 liters. This unit is slightly smaller than the traditional British beer and ale barrel, which held 5.875 cubic feet or 166.36 liters. There are other official barrels, defined in certain U.S. states; most of them fall in the general range of 30-40 gallons. A barrel of beer in the U.S., for example, is usually 31 U.S. gallons (117.35 liters). The origin of the standard symbol bbl is not clear. The "b" may have been doubled originally to indicate the plural (1 bl, 2 bbl), or possibly it was doubled to eliminate any confusion with bl as a symbol for the bale (see above). Note: Some web sites are claiming that "bbl" originated as a symbol for "blue barrels" delivered by Standard Oil in its early days; this is incorrect because there are citations for the symbol at least as early as the late 1700s, long before Standard Oil was founded." (http://www.unc.edu/~rowlett/units/dictB.html)

[Josef]

I tried to find information for this years ago and came up empty. It seems to be a cosmic mystery from the feds.

[Moonlight]

Mike,
What info I have came from A History of English Ale and Beer by Monckton.

A few ideas came to mind. One is that when the book referred to the hopped beer barrel of 32 gallons, the breweries had a set return allowance of 2 gallons per barrel for sediment. Could it be that the usable value of a barrel was 30 gallons, and that the earlier 36 gallon ale barrels had a sediment of about 6 gallons? It was basically straight from the fermenter but that still seems excessive. Obviously no dry hops would be involved before 1400AD! Another idea for the 32 number was that the Flemish barrels at that time that were imported to England with hopped beer would have been some Continental capacity, and that the English could have just copied the size either for competition sake or sentimentality.

Another thought about the US barrel relates to the alcohol law concept that required alcohol to be in unusual capacity containers...like the old 1/5 gallon bottles which has become the 750ml today. The Feds didn't want people to use uncontrollable quart canning jars for legal booze, and could control who got the legal containers.

Or, maybe the 31 gallon size was particularly cost-efficient for construction based on a vessel handling pressure...

Or the US brewers just used old English wine barrels!

I believe the bbl refers to plural of bl, just as "pages" is abbreviated "pp" instead of "pgs."

[Brett0424]

I believe the bbl refers to plural of bl, just as "pages" is abbreviated "pp" instead of "pgs."

I always thought the extra B in Bbl stood for "British"

[mic_mac]

I believe the bbl refers to plural of bl, just as "pages" is abbreviated "pp" instead of "pgs."

I always thought the extra B in Bbl stood for "British"

. . . & I was told by a fellow British brewer (& from books too, I think?) that it meant "Brewer's Barrels"!
(to differentiate from the other volumes used in a barrel of oil, etc)

I have seen some Brit brewers use "Brl" too though.

I guess if you ask 3 brewers . . .

Cheers
MikeMcG