Sunday, 1 March 2015

German brewing in the 1970’s – fermentation (part two)

What’s the best fermentation system? Who hasn’t asked themselves that while soaking in the bath or bobbing along to work on the bus, some grey winters day?

You’re in luck, because Kieninger is going to tell us. Or at least give us his opinion. He worked at Weihenstephan, so he must be right, musn’t he?

“Table XII also shows the most simple and effective method for the fermentation and maturation of lager beers of high quality in the light of modern knowledge. Primary fermentation is carried out in closed vessels, so that it is possible to collect the carbon dioxide and any required temperature may be applied. After reduction of diacetyl the green beer is cooled by plate coolers to a temperature of 0°C and after remaining at this temperature for 2-3 weeks for stabilization it is carbonated and filtered. The only analytical controls required are diacetyl and carbon dioxide and the carbon dioxide content may be controlled by in-line instrumentation.”
Journal of the Institute of Brewing, Volume 83, Issue 1, March-April 1977, page 76.

Lager in just 28 days. I’m not sure he’s convinced me about that. I’m sure it’s a cost-efficient way of brewing. But what about the flavour of the beer? That doesn’t get a look in. Notice that it’s not even taken into consideration.

The best Lagers I’ve had I mostly knew were open-fermented, lagered for months rather than weeks and were naturally carbonated.

I’m going to repeat that table, because it’s a while since the last post in this series:

TABLE XII. Comparison of Fermentation and Maturation Systems.
Method Primary fermentation Transfer Lagering
Classical 7 days at 9°C Beer with 3-5% residual extract cooled to 4°C 35-50 days with temperature reducing from 3° to 0°C
Using Kräusen 7 days at 9º-10°C Beer with 2% residual extract cooled to 4°C. 10-12% Krausen with 8% residual extract added 14-28 days with temperature reducing from 4° to 0°C
Under pressure at high temperature (Champagne Wheat Beer) 3 days at 16°C or 4 days at 14°C under pressure Beer with 2% residual extract 2.0 bar pressure cooled to 0°C 7-14 days stabilization at 0°C 
Modern development 7 days at 12-14°C with CO2 collection Attenuated beer carbonated and cooled to 0°C 14-21 days stabilisation at 0°C and final carbonation

This next bit is interesting, even though it slightly baffles me:

“Fig. 2 illustrates the relationship between the time necessary to reduce diacetyl content to a value of 0.1 mg/litre and maturation temperature. At a temperature of 30°C, 48 hours are sufficient to reduce the diacetyl content to <0.1 mg/litre without addition of Kräusen but, at 8.5°C, eighteen days are necessary to reduce the diacetyl content to the same value. The addition of Kräusen also allows a reduction of diacetyl at higher temperatures, but additional 2-acetolactate is formed during secondary fermentation, so that a new time-consuming reduction phase is necessary.”



Fig. 2. Behaviour of 2-acetolactate (as diacetyl) during different maturation conditions following primary fermentation at 8.5°C. Curve A = maturation at 8.5°C with kräusen, B = 85°C without kräusen, C = 15°C with kräusen, D = 20°C with kräusen, E = 30°C with kräusen, F = 30°C without kräusen.
Journal of the Institute of Brewing, Volume 83, Issue 1, March-April 1977, page 76.

Oh, I get it. You can break down diacetyl at a higher temperature if you kräusen, the fermentation of the kräusen creates more diacetyl. And that also needs to be broken down. Sounds like you need to add more kräusen then. Only joking. But what is he recommending ? I’m confused.

“The development of isoamyl alcohol during primary fermentation at different temperatures with and without pressure is shown in Fig. 3. Isoamyl alcohol content increases



Fig. 3. Iso-amyl alcohol content during primary fermentation in relation to temperature and pressure. Curve A = fermentation at 20ºC, B = 20°C with pressure, C = 16°C, D= 16°C with pressure, E = 12°C. F = 12°C with pressure, G = classical fermentation at 8-S°C.

with increasing temperature but the use of pressure results in a decrease of about 5 % at any given temperature.”
Journal of the Institute of Brewing, Volume 83, Issue 1, March-April 1977, page 77.

This one has totally lost me. Be glad for an explanation by any brewing technicians out there.

Just looked up isoamyl alcohol on this wonderful new thing they have called the internet. A higher alcohol . . . . that tastes like banana. I get why Kieninger is so interested in it, being a brewer of Weissbier.

Still one more bit to go. Where fermentation systems are compared.

Saturday, 28 February 2015

Cask beer in the 1950’s – finings

This is such fun. And just wait until we get to the next chapter which deals with handling cask beer in the pub. That’s a real eye-opener.

Let’s get started.

Fining
The composition of finings has already been described, also reason why they are used. Their aim is to effect as rapidly as possible the condition of clarity which, provided the beer has been properly brewed, would doubtless have resulted spontaneously in the long run. It remains now to deal with the quantity of finings which should be used, and the best time at which to use it.”
"Brewing Theory and Practice" by E. J. Jeffery, 1956, page 246.

So they are a shortcut to clarity, really. Stock Pale Ales in the 19th century weren’t usually fined but expected to drop crystal clear during the long maturation process. I wish some modern brewers would take note that unfined doesn’t mean that the beer has to look like mud in the glass.

This is an interesting point:

“It is hardly necessary to point out that the addition of finings, besides increasing the sludge and bottoms, takes something out of the beer and decreases the palate-fullness. Wherever possible, especially in the case of stock ales and beers for bottling, the use of finings should be dispensed with. Where necessary, as is always the case with running ales, the least possible quantity should be used which is compatible with satisfactory results. One pint of well-made finings per barrel should be the maximum quantity used for running beers, one and a half pints for pale ales, where the finings are called upon to do more work on account of the large amount of hops present in the cask. Even these quantities may be reduced where the finings are made from the best Saigon leaf. This leaf undoubtedly has very strong fining powers. Curiously enough, these finings are rather deceptive in appearance. They seem to be weak and unduly thin. The appearance is deceptive, however, and a proof that apparent strength as revealed by viscosity is not always reliable.”
"Brewing Theory and Practice" by E. J. Jeffery, 1956, page 247.

So maybe the anti-finings brigade do have a point. Finings thin a beer out. Still doesn’t mean I want to drink a pint of sludge, though.

The large amount of hops in Pale Ales would be the dry hops. Though surely a running Bitter would also be dry hopped. He seems to be assuming that running beers were always Mild, which wasn’t usually dry hopped.

Now the tricky question or when to add finings:

“The question of when most suitably to add finings is a debatable one. At one time opinion was in favour of fining in the houses, but with the quicker deliveries that are now possible with modern transport, the major objection to fining in the brewery is removed. If finings are added just prior to despatch from the brewery, the beer will fine satisfactorily within a few hours of its receipt at the cellar of the house. When fining in the houses was the rule, it was sometimes found that better fining was achieved when both beers and finings had been delivered together and stored in the same cellar not less than 24 hours previous to the beer being fined down. Both beers and finings had become acclimatized to the surrounding temperatures, and the action of the finings was more regular and efficient than was the case when the beers were fined down at the brewery. Few breweries now fine in the houses, however.

The advantage of fining at the brewery lies in the knowledge that the job has been done properly. Also, a certain quantity of beer is saved per cask, which in some breweries means quite a large barrelage per annum. Against this might be placed the poor results which could be obtained due to exposure of the fined beer to many variations in temperature in the course of delivery.”
"Brewing Theory and Practice" by E. J. Jeffery, 1956, page 247.

So fining had first mostly been done in pubs, but had shifted to the brewery. I’m surprised at fining only taking a few hours after delivery. I’d have thought 24 hours was more like it. Though I know that the Nottingham breweries’ beer used to drop bright pretty quickly.

I can understand why brewers wanted to do the fining themselves. They had more control over what went on and removed a possibility of the landlord cocking it up. You’ll have noticed that the author clearly doesn’t trust publicans to handle beer properly.

There were times when fining needed to be done earlier, even before racking:

“Sometimes one hears of fining taking place in the racking back. It is a practice of which we  are not in favour unless the fermentation has been very sluggish, and the emission of yeast unsatisfactory. Of course, if the beer is yeast-bitten, and it is essential to avoid the introduction to the cask of a large amount of undesirable sludge and sediment, part fining in the racking square is not only advisable, but necessary.”
"Brewing Theory and Practice" by E. J. Jeffery, 1956, pages 247 - 248.

Only to be done when the fermentation hadn’t gone well and the beer still contained large amounts of yeast.

Next time it gets really exciting when we learn what went on in the pub.

Friday, 27 February 2015

Materials used in brewing in the USA 1955 - 1975

You know what to expect by now. Numbers. Lots and lots of numbers and bugger all words. I’m saving up the words for people who pay me for them.

Let’s start with the raw numbers before I waste too many words on you.

Materials used in brewing in the USA 1955 - 1975 (lbs)
Year Production (barrels) Malt Corn and corn products Rice Wheat Barley Sorghum grains and sorghum products Soybeans and soybean prods. sugar and syrups
1955 89,791,154 2,627,010,323 913,693,701 375,111,692 5,423,575 357,920 1,601,610 108,604,325
1956 90,697,911 2,650,652,911 871,955,351 424,954,817 3,679,525 10,000 38,700 1,181,776 109,404,864
1957 89,881,935 2,617,645,452 944,065,897 354,691,869 2,220,600 1,300 1,056,631 101,768,983
1958 89,010,812 2,577,543,842 954,414,553 336,354,124 1,971,900 495,000 649,000 1,143,739 97,209,348
1959 90,973,768 2,613,176,446 1,012,356,240 330,960,223 1,414,500 173,700 1,309,782 93,312,135
1960 94,547,867 2,697,409,939 1,058,989,007 351,812,764 1,426,000 45,000 1,419,098 98,684,775
1961 93,496,452 2,657,456,124 1,038,015,118 345,488,387 1,297,800 739 15,200 1,402,881 102,447,112
1962 96,417,543 2,715,251,671 1,075,306,335 337,923,616 1,206,000 60,340 1,526,045 121,331,649
1963 97,961,421 2,745,427,657 1,159,394,969 295,876,926 605,800 9,600 5,300 1,545,061 115,964,649
1964 103,017,915 2,885,121,764 1,265,020,486 273,811,073 575,600 3,218,132 1,618,204 106,371,666
1965 108,015,217 3,015,521,588 1,325,891,671 311,082,178 514,500 3,321,415 1,639,433 97,422,892
1966 109,736,341 3,071,600,745 1,316,086,216 334,865,023 481,365 1,618,239 98,792,117
1967 116,564,350 3,270,980,966 1,375,625,956 379,100,298 403,850 12,169,766 1,656,090 101,579,961
1968 117,523,511 3,309,955,668 1,302,371,115 394,510,574 332,600 1,600 41,452,889 1,761,403 120,504,135
1969 122,657,497 3,432,352,177 1,334,548,982 413,854,584 278,800 65,800 43,538,850 1,732,345 142,879,875
1970 134,653,881 3,721,405,457 1,448,830,267 506,065,825 229,200 2,055,860 15,027,460 1,736,287 202,416,492
1971 134,091,661 3,678,737,262 1,463,110,324 501,336,677 189,375 93,580 999,050 2,211,808 208,959,625
1972 140,326,680 3,853,687,171 1,518,935,036 536,974,228 158,800 79,560 778,270 1,839,278 199,423,919
1973 143,013,573 3,898,435,622 1,467,331,844 558,777,431 124,165 87,830 1,844,900 267,265,264
1974 153,053,027 4,172,512,952 1,518,206,361 593,190,144 52,944 1,578,736 310,933,052
1975 157,870,017 4,224,756,179 1,618,954,486 379,381,639 1,791,400 1,522,377 393,453,003
Source:
Various editions of the "The Brewers Almanac"


Obviously they’re much easier to understand expressed as percentages:

Materials used in brewing in the USA 1955 - 1975 (%)
Year Malt Corn and corn products Rice Wheat Barley Sorghum grains and sorghum products Soybeans and soybean prods. sugar and syrups
1955 65.16% 22.66% 9.30% 0.13% 0.01% 0.04% 2.69%
1956 65.26% 21.47% 10.46% 0.09% 0.00025% 0.00095% 0.03% 2.69%
1957 65.09% 23.48% 8.82% 0.06% 0.00003% 0.03% 2.53%
1958 64.93% 24.04% 8.47% 0.05% 0.01% 0.02% 0.03% 2.45%
1959 64.48% 24.98% 8.17% 0.03% 0.00% 0.03% 2.30%
1960 64.07% 25.16% 8.36% 0.03% 0.00% 0.03% 2.34%
1961 64.09% 25.04% 8.33% 0.03% 0.00002% 0.00% 0.03% 2.47%
1962 63.85% 25.29% 7.95% 0.03% 0.00% 0.04% 2.85%
1963 63.57% 26.85% 6.85% 0.01% 0.00022% 0.00% 0.04% 2.69%
1964 63.61% 27.89% 6.04% 0.01% 0.07% 0.04% 2.35%
1965 63.41% 27.88% 6.54% 0.01% 0.07% 0.03% 2.05%
1966 63.68% 27.29% 6.94% 0.01% 0.03% 2.05%
1967 63.62% 26.76% 7.37% 0.01% 0.24% 0.03% 1.98%
1968 64.01% 25.19% 7.63% 0.01% 0.00003% 0.80% 0.03% 2.33%
1969 63.93% 24.86% 7.71% 0.01% 0.00123% 0.81% 0.03% 2.66%
1970 63.10% 24.57% 8.58% 0.004% 0.03% 0.25% 0.03% 3.43%
1971 62.82% 24.99% 8.56% 0.003% 0.00160% 0.02% 0.04% 3.57%
1972 63.05% 24.85% 8.79% 0.003% 0.00130% 0.01% 0.03% 3.26%
1973 62.94% 23.69% 9.02% 0.002% 0.00142% 0.03% 4.31%
1974 63.25% 23.02% 8.99% 0.00080% 0.02% 4.71%
1975 63.82% 24.46% 5.73% 0.03% 0.02% 5.94%
Source:
Various editions of the "The Brewers Almanac"


Malt usage has bottomed out at around 63%. While corn rose to almost 28%, before falling back to 24%, just a little higher than in 1955. Rice is all over the place and shows no real trend. Sorghum, soya and unmalted wheat and barley are only used in tiny amounts. Sugar hovered around 2% then shot up to almost 6% in 1975.

Now let’s look at those figures in pounds per barrel:

Materials used in brewing in the USA 1955 - 1975 (lbs/brl.)
Year Malt Corn and corn products Rice Wheat Barley Sorghum grains and sorghum products Soybeans and soybean prods. sugar and syrups other materials total
1955 29.3 10.2 4.2 0.06 0.004 0.02 1.2 44.98
1956 29.2 9.6 4.7 0.04 0.0001 0.0004 0.01 1.2 44.75
1957 29.1 10.5 3.9 0.02 0.01 1.1 44.63
1958 29 10.7 3.8 0.02 0.006 0.007 0.01 1.1 44.64
1959 28.7 11.1 3.6 0.02 0.002 0.01 1 44.43
1960 28.5 11.2 3.7 0.02 0.0005 0.02 1 44.44
1961 28.4 11.1 3.7 0.01 0.0002 0.02 1.1 44.33
1962 28.2 11.2 3.5 0.01 0.0006 0.02 1.3 44.23
1963 28 11.8 3 0.006 0.0001 0.00005 0.02 1.2 0.0002 44.03
1964 28 12.3 2.7 0.006 0.03 0.02 1 0.005 44.06
1965 27.9 12.3 2.9 0.005 0.03 0.02 0.9 0.001 44.06
1966 27.5 12 3.1 0.004 0.01 0.9 0.0000 43.51
1967 28.1 11.8 3.3 0.003 0.1 0.01 0.9 44.21
1968 28.2 11.1 3.4 0.003 0.00001 0.35 0.01 1 44.06
1969 28 10.9 3.4 0.002 0.00005 0.35 0.01 1.2 0.05 43.91
1970 27.6 10.8 3.8 0.002 0.02 0.11 0.01 1.5 0.05 43.89
1971 27.4 10.9 3.7 0.001 0.0007 0.007 0.02 1.6 43.63
1972 27.5 10.8 3.8 0.001 0.0006 0.006 0.01 1.4 43.52
1973 27.3 10.3 3.9 0.0008 0.0006 0.01 1.9 43.41
1974 27.2 9.9 3.9 0.0003 0.01 2 43.01
1975 26.8 10.3 3.7 0.01 0.01 2.5 43.32
Source:
Various editions of the "The Brewers Almanac"


There’s a small decline in the amount of fermentable materials per barrel, presumably reflecting a small decline in average gravity. Something like this:

Year estimated average OG
1955 1046.20
1956 1045.96
1957 1045.83
1958 1045.85
1959 1045.63
1960 1045.64
1961 1045.53
1962 1045.42
1963 1045.21
1964 1045.25
1965 1045.24
1966 1044.69
1967 1045.41
1968 1045.25
1969 1045.10
1970 1045.08
1971 1044.81
1972 1044.69
1973 1044.58
1974 1044.17
1975 1044.49


Hops next:

Hop usage in the USA 1955 - 1975
Year hops lbs hops lbs./ bbl.
1955 33,736,717 0.38
1956 32,938,442 0.36
1957 31,732,968 0.35
1958 30,419,008 0.34
1959 29,642,566 0.33
1960 30,825,243 0.33
1961 29,473,204 0.32
1962 29,896,445 0.31
1963 30,343,524 0.31
1964 30,446,822 0.30
1965 31,562,258 0.29
1966 31,054,401 0.28
1967 30,744,728 0.26
1968 29,231,847 0.25
1969 28,719,722 0.23
1970 38,195,191 0.23
1971 32,135,040 0.24
1972 33,467,886 0.24
1973 34,523,123 0.24
1974 36,777,733 0.24
1975 35,532,533 0.21
Source:
Various editions of the "The Brewers Almanac"


Despite beer output almost doubling in this period, the quantity of hops only slightly increased. Which translates to an almost halving of the pounds per barrel. 0.21 pounds is, er, eff all.

Let’s continue with a comparison with the UK. Raw numbers first:

Brewing materials in the UK 1955 - 1975 (lbs)
year malt unmalted corn rice, maize, etc sugar total malt & adjuncts bulk barrels
1955 967,178,464 5,214,272 53,552,800 171,276,672 1,197,222,208 24,324,623
1956 966,576,240 4,484,256 54,525,856 172,956,896 1,198,543,248 24,187,096
1957 993,716,416 1,549,408 59,607,968 175,243,376 1,230,117,168 24,839,755
1958 967,960,000 1,200,304 60,868,304 171,135,664 1,201,164,272 24,129,462
1959 995,160,768 896,784 66,080,672 175,728,224 1,237,866,448 25,023,044
1960 1,053,568,320 1,007,328 64,204,224 184,894,416 1,303,674,288 26,313,796
1961 1,108,484,944 945,840 65,499,392 195,594,448 1,370,524,624 27,600,860
1962 1,116,088,176 1,197,280 68,180,560 196,868,672 1,382,334,688 27,736,049
1963 1,122,290,288 1,557,472 72,167,088 196,114,128 1,392,128,976 27,942,561
1964 1,186,297,056 2,896,432 79,713,648 205,509,472 1,474,416,608 29,485,128
1965 1,189,365,072 6,875,904 82,308,576 203,116,592 1,481,666,144 29,579,855
1966 1,196,996,640 14,854,672 86,181,872 207,517,632 1,505,550,816 30,178,056
1967 1,211,628,992 16,429,504 86,881,200 213,954,160 1,528,893,856 30,751,420
1968 1,194,570,496 13,599,488 83,823,376 212,535,120 1,504,528,480 30,763,106
1969 1,272,590,480 19,633,488 86,823,968 238,948,304 1,617,996,240 32,211,837
1970 1,284,913,504 26,237,232 86,399,152 247,252,880 1,644,802,768 32,940,567
1971 1,334,859,232 30,776,480 84,139,440 271,794,656 1,721,569,920 34,360,000
1972 1,355,179,280 71,114,512 50,622,544 286,563,424 1,763,479,760 34,969,310
1973 1,378,987,008 69,291,264 45,776,752 282,339,344 1,776,394,480 35,338,345
1974 1,491,601,328 69,873,328 57,895,600 309,028,608 1,928,398,752 37,893,753
1975 1,513,065,568 83,982,864 72,000,768 297,172,064 1,966,221,264 38,238,657
Sources:
1954 - 1968: 1971 Brewers' Almanack, page 54
1969 "The Brewers' Society UK Statistical Handbook 1973", pages 16 - 17.
1970 - 1975 "The Brewers' Society UK Statistical Handbook 1978", page 19.
1970 - 1975 bulk barrelsStatistical Handbook of the British Beer & Pub Association 2005, p. 7



But the percentages are more use:

Brewing materials in the UK 1955 - 1975 (%)
year malt unmalted corn rice, maize, etc sugar lbs per Imp. barrel lbs per US barrel
1955 80.79% 0.44% 4.47% 14.31% 49.2 35.3
1956 80.65% 0.37% 4.55% 14.43% 49.6 35.5
1957 80.78% 0.13% 4.85% 14.25% 49.5 35.5
1958 80.59% 0.10% 5.07% 14.25% 49.8 35.7
1959 80.39% 0.07% 5.34% 14.20% 49.5 35.5
1960 80.82% 0.08% 4.92% 14.18% 49.5 35.5
1961 80.88% 0.07% 4.78% 14.27% 49.7 35.6
1962 80.74% 0.09% 4.93% 14.24% 49.8 35.7
1963 80.62% 0.11% 5.18% 14.09% 49.8 35.7
1964 80.46% 0.20% 5.41% 13.94% 50.0 35.9
1965 80.27% 0.46% 5.56% 13.71% 50.1 35.9
1966 79.51% 0.99% 5.72% 13.78% 49.9 35.8
1967 79.25% 1.07% 5.68% 13.99% 49.7 35.6
1968 79.40% 0.90% 5.57% 14.13% 48.9 35.1
1969 78.65% 1.21% 5.37% 14.77% 50.2 36.0
1970 78.12% 1.60% 5.25% 15.03% 49.9 35.8
1971 77.54% 1.79% 4.89% 15.79% 50.1 35.9
1972 76.85% 4.03% 2.87% 16.25% 50.4 36.2
1973 77.63% 3.90% 2.58% 15.89% 50.3 36.0
1974 77.35% 3.62% 3.00% 16.03% 50.9 36.5
1975 76.95% 4.27% 3.66% 15.11% 51.4 36.9
Sources:
1954 - 1968: 1971 Brewers' Almanack, page 54
1969 "The Brewers' Society UK Statistical Handbook 1973", pages 16 - 17.
1970 - 1975 "The Brewers' Society UK Statistical Handbook 1978", page 19.



Malt use has declined by 4 percentage points, while unmalted corn use has increased by the same amount. Rice and maize use is down a bit, while sugar is pretty much unchanged.

Hop usage came as a bit of a surprise:

Hop usage in the UK 1955 - 1975
year bulk barrels hops( lbs) hops lbs/  Imperial barrel hops lbs/  US barrel
1955 24,324,623 24,384,192 1.00 0.72
1956 24,187,096 24,507,840 1.01 0.73
1957 24,839,755 24,092,768 0.97 0.70
1958 24,129,462 23,393,440 0.97 0.70
1959 25,023,044 24,196,144 0.97 0.69
1960 26,313,796 25,353,552 0.96 0.69
1961 27,600,860 26,276,432 0.95 0.68
1962 27,736,049 25,360,944 0.91 0.66
1963 27,942,561 25,375,280 0.91 0.65
1964 29,485,128 26,583,872 0.90 0.65
1965 29,579,855 26,479,488 0.90 0.64
1966 30,178,056 25,997,328 0.86 0.62
1967 30,751,420 24,840,816 0.81 0.58
1968 30,763,106 22,428,448 0.73 0.52
1969 32,211,837 23,674,672 0.73 0.53
1970 32,940,567 24,050,208 0.73 0.52
1971 34,360,000 22,041,824 0.64 0.46
1972 34,969,310 21,118,048 0.60 0.43
1973 35,338,345 20,558,160 0.58 0.42
1974 37,893,753 19,012,672 0.50 0.36
1975 38,238,657 16,686,768 0.44 0.31
Sources:
1954 - 1968: 1971 Brewers' Almanack, page 54
1969 "The Brewers' Society UK Statistical Handbook 1973", pages 16 - 17.
1970 - 1975 "The Brewers' Society UK Statistical Handbook 1978", page 19.



The percentage decline in the hopping rate is even than in the US. It seemed a bit strange to me. This table including hop products might explain it:

Hop and hop products usage in the UK 1955 - 1975
year hops preparations of hops hop substitutes
1955 217,716 92 27
1956 218,820 110 42
1957 215,114 91 28
1958 208,870 102 24
1959 216,037 107 29
1960 226,371 111 24
1961 234,611 112 10
1962 226,437 180 17
1963 226,565 246 25
1964 237,356 474 37
1965 236,424 599 57
1966 232,119 623 165
1967 221,793 672 104
1968 200,254 732 113
1969 211,381 hop powder
1970 214,734 1,614 -
1971 196,802 5,098 945
1972 188,554 3,937 3,917
1973 183,555 4,744 5,610
1974 169,756 9,173 10,413
1975 148,989 13,799 14,527
Sources:
1954 - 1968: 1971 Brewers' Almanack, page 54
1969 "The Brewers' Society UK Statistical Handbook 1973", pages 16 - 17.
1970 - 1975 "The Brewers' Society UK Statistical Handbook 1978", page 19.


There’s a big increase in the use of hop products. Unfortunately, I don’t know how to convert that into the equivalent quantity of hops.

I’ll finish with average OG in the UK:

Average OG in the UK 1955 - 1975
year OG
1955 1037.13
1956 1037.22
1957 1037.42
1958 1037.48
1959 1037.52
1960 1037.25
1961 1037.41
1962 1037.70
1963 1037.70
1964 1037.66
1965 1037.67
1966 1037.63
1967 1037.46
1968 1037.36
1969 1037.14
1970 1036.90
1971 1036.90
1972 1036.90
1973 1037.00
1974 1037.10
1975 1037.30
Sources:
Brewers' Almanack 1962, p. 48
Statistical Handbook of the British Beer & Pub Association 2005, p. 7
Brewers' Almanack 1971, p. 45


Pretty dull, eh? The variation is tiny, with a low of 1036.9 and a high of 1037.7. In fact these two decades show the least change of any in the 20th century.

I would promise a third set of these numbers, but I’ll need to harvest the British ones. I’ve only got them up to 1978 at the moment.