Friday, 27 June 2008


There are fascinating insights to be gained by comparing the gravity books and brewing logs. Specifically, what was happening to beer between leaving the brewery and being pulled into a customer's glass.

The brewing logs tell what the brewer intended his beer to be. The gravity books what was actually served in pubs. The two rarely match.

19th Century
Frederick Accum did something similar at the beginning of the 19th century. He sampled beers in the great Porter breweries and then in pubs. One average, by the time they were served, beers were 10 -15% weaker. A century or so later, not much seemed to have changed.

Samples of brown stout with which I have been obligingly favoured, whilst writing this Treatise, by Messrs. Barclay, Perkins, & Co.—Messrs. Truman, Hanbury, and Co.—Messrs. Henry Meux and Co.—and other eminent brewers of this capital—afforded, upon an average, 7,25 per cent. of alcohol, of 0,833 specific gravity; and porter, from the same houses, yielded upon an average 5,25 per cent. of alcohol, of the same specific gravity*; this beer received from the brewers was taken from the same store from which the publicans are supplied.

* The average specific gravity of different samples of brown stout, obtained direct from the breweries of Messrs. Barclay, Perkins, and Co. Messrs. Truman, Hanbury, and Co. Messrs. Henry Meux and Co. and from several other eminent London brewers, amounted to 1,022; and the average specific gravity of porter, from the same breweries, 1,108 [I think this should be 1,018].

It is nevertheless singular to observe, that from fifteen samples of beer of the same denominations, procured from different retailers, the proportions of spirit fell considerably short of the above quantities. Samples of brown stout, procured from the retailers, afforded, upon an average, 6,50 per cent. of alcohol; and the average strength of the porter was 4,50 per cent. Whence can this difference between the beer furnished by the brewer, and that retailed by the publican, arise? We shall not be at a loss to answer this question, when we find that so many retailers of porter have been prosecuted and convicted for mixing table beer with their strong beer; this is prohibited by law, as becomes obvious by the following words of the Act.

"If any common or other brewer, innkeeper, victualler, or retailer of beer or ale, shall mix or suffer to be mixed any strong beer, ale, or worts, with table beer, worts, or water, in any tub or measure, he shall forfeit £50." The difference between strong and table beer, is thus settled by Parliament.

"A Treatise on the Adulterations of Food" by Frederick Accum, 1820, pages 172 - 175.

20th century
The first thing that tipped me off to this possibility was the variation in gravity for different samples the same beer in the Whitbread and Truman Gravity Books. With the exception of traumatic periods like wartime, brewers didn't fiddle with the gravity of a beer from month to month. It stayed constant for years on end. I know that from the brewing logs. And they were professional enough to be able to hit the target gravity pretty much 100% or the time.

Sorry, I should have said variation in the gravity of draught beer. Bottled beers are much more constant. Which is a real giveaway as to the underlying cause: adulteration. The landlord can't really fiddle with bottled beer. Not so with draught beer.

Let's look at an example from Barclay Perkins. Here are five examples of their KK, or Burton, all from 1936. Four are from the Truman Gravity Book, one from the Barclay Perkins brewing logs.

The beer as brewed was a nice round 1056 gravity. The pub samples vary from 1048.8 to 1055.9. Only one matches the brewery gravity. As these have been calculated, we need to allow from some margin of error. So I'm willing to give the 1053.9 sample the benefit of the doubt. The other two are far too low. 10% and 13% too low to be precise. Something has clearly happened to the beer. But what?

My guess would be slops of weaker beer being put into the KK cask.

But take a look at the figures for Barclay Perkins ordinary Mild, X Ale:

Here all the pub samples have a higher gravity than the brewing log. How can this be? When I was younger, a reason people often gave for not drinking Mild was that the slops from all the other beers were put into it. Being dark, it was hard to spot. I was sceptical about this theory at the time. But that's exactly what these numbers suggest. As X would usually be the weakest draught beer, slops from anything else would raise its gravity.

This begs the question. Adulteration seems to have been common between 1800 and 1940. Does it still occur now?


dann paquette said...


Those are some great stats! I can chime in with some experience I've had in Yorkshire.

Just about every pub cellar I've been in I've seen steel funnels lying around or on top of casks. One time when I was trying to fix an air-intake problem on one line, pulling beer through as I went, the publican was filling pitchers and running them downstairs as I did so.

I've also seen pubs that clean a line, rinse the line, pull the beer through and go back downstairs with the pitchers (of varying shades of amber).

Now it may be a stretch to go from there to blending cheap with pricey. I suspect that at the rate a typical pub would go through our beer it just wouldn't be worth the effort.

But are miss-pours, half empties and slop trays poured into a bucket and carted back downstairs? I suspect this does happen. My palate tells me this happens anyway. We've gone into pubs after crediting "ullage" for sour, cloudy beer and this practice would be the most logical explanation (especially considering that the other 79 casks from that batch went fine).

But I like the idea of taking a hydrometer to the pubs and taking a cheeky look.

I also wonder about mild ale once again. Is this why so many of them taste so much like caramel colouring? Do publicans have this stuff on hand? I swear I had a pint of Tomothy Taylor Mild that tasted like it was water, a small amount of bitter and 75% caramel colouring.



Ron Pattinson said...

At the period in question, a typical London range of draught beers was something like this: Mild, Bitter, Burton and Stout. If the slops are getting mixed up, then you can't really put them back into the Bitter, because it's going to mess up the colour. The obvious choice would be the Burton or Mild, where it's least likely to be noticed.

Isn't Timothy Taylor's Dark Mild just the Golden Best with caramel? I seem to remember that it was illegal to store sugar of any kind in a pub cellar.

I don't think I would dare take a hydrometer into a pub. Just discretely taking some of the beer away would be safer. I think it would be very revealing.

Stonch said...

Just about every pub cellar I've been in I've seen steel funnels lying around or on top of casks.

I think this is pretty much unheard of in Britain.

Stonch said...

PS. I just reread your comment and realised you were referring to pubs in Yorkshire. Yet I'd stand by what I've said. Slopping beer back into casks wouldn't be worth the effort. When a technician comes to work on your line you get credited for any beer wasted. When you line clean you either pour the beer away, or drink it with staff/regulars. We use some for cooking and pour the rest away.

Ron Pattinson said...

Stonch, I wouldn't have expected you to be anything but an honest landlord. But is everyone as principled?

It's good to have two opinions from within the trade. Even though they do confusingly 100% contradict each other. If just one more member of the trade pipes up, I'll be able to draw a definitive conclusion.

I'm not bringing this up to have a go at anyone. It's just that the long tradition of adulteration has been little discussed. For fairly obvious reasons. It wasn't something you'd want to make public. Almost everything on the topic is based on rumour.

zythophile said...

There was a saying in the 19th century about recycling waste into the porter: "Black beer tells no tales". In the 20th century, right through to the 1950s, at least, the recycling of waste beer into the mild was formalised to the extent that all the beer from the driptrays ran down into a ceramic bucket hanging from the cellar roof, which had its own little pump designed to put the waste back into the mild as it was drawn, a teaspoonful at a time. "Bulk" waste beer recycling also went into the mild, as this generally had little or no yeast in the cask (because it wasn't meant to have a secondary fermentation in the pub cellar) - you couldn't put waste beer into the bitter because it would kick up the sediment as it went in, and make the beer cloudy ... there are one or two books written by landlords (or ex-landlords) that mention this kind of activity, but I'm not at home so I can't tell you their titles ...

Ron Pattinson said...

Zythophile, fascinating stuff.

The gravities of Bitter samples seem much more consistent than those for Mild and Bitter. The ones for ordinary Mild are almost never the same.

Be good to get the titles of those books, when you're at home. I'm intrigued. You don't happen to know a good German brewing manual from 1900 - 1910, do you?