Brewing in the 1950’s – how to lay out your brewery (part one)

The surprising success of stuff about how to construct a brewery in the 1950’s has prompted me to continue. Ever the populist that I am.

Jeffery gives what looks like very sound advice about the layout of a brewery. Mostly concerned with eliminating possible sources of infection. Something that’s one of a brewer’s greatest fears.

I can’t help thinking of the sad end of Home Ales of Nottingham. I drank their beers a lot when I was younger. They were some of the most reliably sound in the country. I don’t think I can recall a single pint that was in poor condition. The company was well run and profitable. So they decided to build a brand, spanking new brewhouse.

That’s when the trouble started. Because there was a source of infection in the brewery. From that time on, their beer was never right. Try as they might they couldn’t track down the source of the infection. Eventually they gave up and sold up to Scottish & Newcastle. It’s a cautionary tale about the importance of a good brewery design.

“The danger of bacterial infection begins from the time when the wort leaves the copper, since no further sterilization is possible thereafter. It should, however, be comparatively easy to arrange subsequent departments, and the plant through which the beer passes, in such a manner that little pumping is necessary, and the minimum length of piping is involved. The copper, in order to carry out the advised system of gravitation, would be in the highest storey of the building. This arrangement makes it easier, also, to convey away the volumes of steam generated by boiling. Immediately below should be placed the hop-back, which should be an enclosed vessel with a steam chute leading from the top to outside the building. If the steam thrown off at this period is allowed to permeate the department, roof, walls and everything with which it comes into contact will in time become smothered by a sticky, sugary deposit, forming a breeding ground for bacteria and other undesirable organisms at the very place where it is essential to avoid them. Many breweries still have open coppers and hop-backs. Wherever possible these should be fitted with covers and steam vents. Where this is not practicable, special care should be taken to ensure that condensed water does not drop from the ceiling or rafters overhead into the hop-back. However, these expedients do not concerns us at this stage, as we are here considering the best type of plant for a new brewery.”
"Brewing Theory and Practice" by E. J. Jeffery, 1956, pages 22 - 23.

The shorter the length of piping, the fewer places an infection can lurk.

That’s something I’d never considered: steam condensing on the roof and falling back into the hop-back. The ceiling isn’t likely to be the cleanest spot in a brewery. Steam sounds like quite dangerous stuff, beyond the obvious scalding risk.

“Immediately below the hop-back should be placed the wort receiver. In a modern brewery this will be a deep vessel. At one time the wort would have been discharged into a cooler—a large, open, shallow vessel - which was thought to be essential at this stage. The open cooler has passed into disfavour as a potential source of infection and is to be found only in a very few breweries.”
"Brewing Theory and Practice" by E. J. Jeffery, 1956, page 23.

Cooler. Remember that word. We’ll be getting to it again later. It’s replacement, the wort receiver, was a different shape and had a different function. It didn’t cool the wort, but merely held it and fed the refrigerator, where all the cooling was done.

We’ll be looking at that in more detail next time.

T & J Bernard's New Edinburgh Brewery (part two)

This time we get to look at the actual brewing equipment at Bernard's Slateford Road brewery. Exciting or what?

We'll start with two of the more prosaic pieces of brewery kit: the grist hopper and hot liquor tanks. Not very glamorous, but certainly essential.

"Reluctantly leaving this beautiful prospect, we resumed our studies, and passed across a foot bridge to take a look at the grist hopper then being filled from the elevator. It is a large square iron receiver, tapering towards the bottom, capable of holding eighty quarters of malt, and is placed over the tuns below. To view these vessels we had to descend to a lower stage or gallery On our way we came to two hot-water tanks, each holding 120 barrels, protruding a few feet from the wall, the larger and hidden portion being carried over the roof of the next house, while another boiling tank is situated in the opposite corner of the building. They are both heated by steam coils from the exhaust pipe of the engine, and in front of them are two steam automatic traps for cutting off the condensed water."
"Noted Breweries of Great Britain and Ireland, vol. 3", Alfred Barnard, 1890, pages 118 - 119.

That's very green, isn't it? Using the exhaust of the steam engine to heat the water tanks. I can't help trying to fit the numbers together any time I read a passage of Barnard that includes any. To mash and underlet - the initial phase of the mashing process - about 3 barrels of water are needed per quarter. So 80 quarters would require 240 barrels. Or the exact capacity of the two hot water tanks. That's reassuring.

"The mash-tun stage, which is a splendid floor lighted by thirteen windows, contains three mash-tuns, two holding forty-six quarters each, and the other twenty-six quarters. They are copper vessels, encased with pine, and each contains the usual sparging apparatus and gun-metal draining plates. The grist hopper, before referred to, which is suspended over them, is connected with a large size Steel's mashing machine, which mashes three quarters of malt a minute, and serves the three vessels. The water used for mashing is obtained from the well, situated three-quarters of a mile from the brewery, by means of two 4.5-inch hydraulic lifting pumps, each having a stroke of 2 feet. These pumps are worked by a power pump at the brewery, which forces water at a pressure of 1,200 lbs. along two tubes, causing it to work like a solid piston-rod of great length, and acting on the plungers of the lifting pumps; these tubes, 1 7/8-inch, 5 w. g. and 1 3/8-inch internal diameter, have been tested at a pressure of 1,800 lbs. per square inch, and are galvanised inside. Between the well and the brewery is a 4-inch wrought-iron delivery pipe, also galvanised inside. The pumps are capable of delivering 1,200 barrels per day of twelve hours. The power pump is driven by the main engine, and requires about seven horse-power to work it."
"Noted Breweries of Great Britain and Ireland, vol. 3", Alfred Barnard, 1890, page 119.

The hopper and Steel's masher are clearly visible at the top left of the illustration. The vessels to the right are, I believe, two of the coppers.

You must be getting used to my brewhouse maths. I wouldn't like to disappoint you. Multiply the mash-tun capacity in quarters by four and you get the approximate capacity in terms of finished beer. That's two of 184 barrels and one of 104 barrels. For a total of 472 barrels per day. Assuming 300 brew days a year gives an annual capacity of just over 140,000 barrels. They weren't actually making anything like that amount. Between 1890 and 1895, the largest amount brewed in a single year was 67,000 barrels. It looks to me like they built the Slateford Road brewery with an eye to the future, with plenty of spare capacity. The optimism of late Victorian brewers is admirable. Just as well they didn't know what was around the corner.

You know as well as I do that it would be unusual if they didn't have a Steel's masher. But here's another excuse for some mathematics. At 3 quarters a minute, it could fill the larger tuns in just over 15 minutes. Much nicer than half an hour of manual stirring with paddles.

Now on to the coppers.

"From the mashing stage we looked over the balustrade and observed, on a lower gallery opposite, three handsome copper vessels, one of them closed with a domed cover, the other two open. They are used for boiling the wort with the hops; two of them boil eighty barrels, and the other 140 barrels at one time. The design of these coppers is a little different from those we have seen before, the curvature being dissimilar, and the crown somewhat higher. The furnaces which heat these vessels are on the paved floor of the brewhouse ; the fuel with which they are fired being raised in barrows by the steam hoist, by means of hinged blocks which lift up as they pass through the trap doors, so that the loaded barrows cannot fall."
"Noted Breweries of Great Britain and Ireland, vol. 3", Alfred Barnard, 1890, page 119.

Once again, there are both open and closed coppers. Why did they have both types? Were the open ones for Pale Ale, as we've seen in other breweries? I can only wildly speculate. Maybe you can help me about their design. It sounds to me as if each copper has its own furnace, placed underneath it. Are these direct-fired coppers? I think they probably are. The alternative would be to use a steam coil, which is how they were heating water in the hot liquor tanks. This is one of the first breweries I've come across in Scotland that does appear to use direct-fired coppers.

The smaller coppers seem a bit small relative to the mash tuns. A 46-quarter mash tun, assuming two roughly equally-sized worts, would require a copper of 90 to 100 barrel capacity. Another indication that they weren't brewing at full tilt. I don't believe that the coppers could handle the wort that all three mash tuns could supply, if running in parallel.

We'll finish with another of the more mundane pieces of equipment, the hop back.

"On a level with this stage there is a hop room for a few days' supply of hops, quite contiguous to the tops of the coppers. The hop-back, another copper vessel, holding 120 barrels, to which the wort now runs, is placed over the coolers in the next building, and contains gun-metal draining plates.

Under the mash-house floor we were shown a movable platform, on wheels of great height, which runs across the floor to enable the brewers men to get at the bottoms of the elevated vessels when required. The mash-tuns all discharge their draff by means of a wooden shoot, which is attached to an iron one leading into the draff-house, a small detached building in the yard."
"Noted Breweries of Great Britain and Ireland, vol. 3", Alfred Barnard, 1890, pages 119 - 120.

Very practical, that, having the hop store next to the top of the coppers. Now there's something I have personal experience of, throwing hops into the copper. That and filling kegs with AK are the only real functions I've ever performed in a brewery. I don't count mouse clicks. The system of removing spent grains (draff) was also neat. At least no poor bugger had to climb into the mashtun and shovel it all out.

Next it's the turn of cooling and fermenting.

Boiling and cooling 1880-1914

I'm really enjoying "Principles & Practice of Brewing" by Walter J. Sykes & Arthur R. Ling, published in 1907. That's why I'll be pestering you with lots more from it in the coming days.

Today it's the turn of boiling and cooling. Exciting, eh? I was thrilled to discover the method of calculating what proportion of the hops needed to go into the different strength worts. A bit sad, aren't I?

It's interesting to see that heat exchangers ("refrigerators") hadn't totally replaced open coolships, as you might have expected. It seems coolships performed other vital tasks, apart from the mere cooling of the wort.



Boiling
There were several reasons for boiling:

- sterilising the wort
- destroying disatase
- coagulating and precipitating out proteins (the "break")
- concentrating the wort
- extracting flavour and tannins from the hops


The wort was brought to the boil as quickly as possible to destroy any remaining disatase which would cause the creation of more maltose if left unchecked. The boil was vigourous and varied in length between one hour and more than two. Around 2 hours was commonest.

Whitbread boiled their strong worts for 80 to 105 minutes and their weak worts for 2 hours. Fullers boiled their worts for between 80 and 120 minutes.

Dome coppers had the advantages of aerating the wort and preventing it from boiling over. The disadvantage was that the hops could disintegrate to such an extent that they no longer opperated as a filter for the wort.

There were many different opinions about the best time to add hops to the wort. Some brewers added them as soon as the wort was put into the copper. Others waited until the wort had begun to boil. Sykes & Ling reckoned that it was best to wait until 15 to to 20 minutes into the boil before adding any hops. Their reasoning was that, some proteins already having been precipitated, this helped the precipitative action of tannins in the hops.

They were also proponents of two hop additions: one 15 or 20 minutes after the start, the second 20 to 30 minutes before the end. In this way not all of the volatile oils would be boiled off. The coarser hops were added first and the finer hops, whose flavour would be better preserved, last. A system of three hop additions was also practised, again with the best-flavoured hops added last.

The brewing logs, unfortunately, only give details about the total length of the boil and do not specify when hop additions took place. Based on what appears in brewing manuals, it's probably safe to assume that two additions were commonplace. When hops of different ages were being used, which was usually the case, it would make sense to have used the freshest hops last, as these would contain the greatest quantity of volatile oils. The older hops would have been used as a source of hop resins and tannins, which would not have been lost to such a great extent as the volatile oils during storage.

Though long boiling also extracted some of the less desirable elements of the hops, it was necessary to dissolve hop resins, which acted as a preservative. "The preservative power of hops is dependent on the soft resins they contain, and these, on excessive boiling, undergo a chemical change and are converted into bodies of a less soluble nature; hence hops should never be boiled a second time. It is highly probable that the long periods which hops are often boiled at the present time might be shortened with advantage."

When worts were boiled sepatately, each was hopped in proportion to its volume and gravity. Let's take as an example a brew of 100 barrels of beer, with a gravity of 21 pounds per barrel (1058º) and 250 pounds of were to be used in the whole batch. The total extract would be 100 * 21, or 2100. A first wort of 67 barrels at 24 pounds per barrel, would have an extract of 67 * 24, or 1608. So the amount of hops to be boiled in it would be 250 (total hops) * 1608/2100, or 191.4. The second wort would have the remainder of the hops: 58.6 pounds.

A patented device called a "hop separator", divided hops into leaves, stalks and lupulin. The leaves were added at the start of the boil, the stalks 15 minutes before the end and the lupulin 10 minutes before the end. The inventor claimed between 10 and 25% fewer hops were needed when using this method.

At the end of the boil, the wort was "turned out", that is run into the hop back. The hops settled onto the false bottom and formed a natural filter so that the wort was drawn off perfectly clear. The spent hops were sparged to release any wort retained in them.



Cooling
Form the hop back, the wort moved on to the coolers. Whilst spread thinly in the shallow coolers, the wort not only rapidly lost heat, but also absorbed oxygen. This oxygen combined chemiccally with some of the contents of the wort. This aeration was vital for the later clarity of the beer.

Whilst in the cooler, the wort deposited a sediment known as "cooler sludge", which was not allowed to get into the fermenting tun. The wort was not allowed to drop below 140º F in the coolers as this would damage the finished beer and make it less stable.

As soon as the wort had dropped in temperature to 140º F, it was run through the refrigerator. Here more oxygen was absorbed, though only in solution, not chemical combination. The wort was cooled to the required pitching temperatuure, usually 58 to 60º F.