Brewing in the 1950’s – coolers

Back with coolers again time for more ranting.

I just want to get one thing off my chest before we start. Coolship is not an English word. It’s a translation of the German or Dutch – Kuhlschiff or koelschip. It’s really irritating when people don’t use the correct English word.

Though by the 1950’s coolers were no longer widely used. In the early 19th century coolers had been the only devices used to cool wort. After the development of refrigerators – a system of pipes through which flowed cold water or brine and over which the wort flowed – these were used in conjunction with coolers rather than replacing them. Partly because coolers still had an important auxiliary role in precipitating out gunk from the wort.

“Wort Receiver. If the brewery is suitably arranged, the wort can pass by gravitation to the wort receiver and thence to the refrigerators. Some brewers consider that the use of a pump between hop-back and refrigerator has an undesirable effect upon the colloidal matter in the wort, dispersing it into smaller particles which may affect the yeast in the fermentation: undeniably, if hop-back filtration is poor, insoluble particles in the wort may get broken up in the pump; but such insoluble matter from the hop-back is objectionable in any case, whether or not its adverse effects are increased if it is in smaller particles. Be that is it may, the amount of such insoluble matter in a wort should be negligible; if it is not, the remedy is to be found in improved hop-back filtration. The present author considers that this objection to pumping is without foundation, and the fact of the matter is that many, if not most, modern breweries pump their wort, either to raise it to a wort receiver on a higher floor, or for the purpose of obtaining sufficient pressure for use with an enclosed refrigerator to get an adequate throughput. “
"Brewing Theory and Practice" by E. J. Jeffery, 1956, page 47.

It sounds here as if the hop-back had replaced the cooler in the function of removing crap from the wort.

Here’s a little more about coolers:

“At one time the wort would have been discharged into a large shallow cooler. The latter was undeniably necessary before the advent of refrigerators. Exposure of the wort to the air, in a shallow vessel, was the only means of cooling in those days. But during that time the wort could pick up innumerable bacteria and wild yeast, a most undesirable feature. The extensive exposed surface of wort was open to infection from any local sources which might exist. In many cases where receivers were substituted for coolers there was an immediate improvement in the quality of the beer. Open coolers are now hardly ever used in top fermentation breweries. A few breweries however still use them, on the grounds that they provide conditions of cooling and an opportunity for sedimentation that are beneficial to the wort. Lager breweries still use them extensively and they are usually housed in enclosed rooms supplied with sterile air.”
"Brewing Theory and Practice" by E. J. Jeffery, 1956, pages 47 - 48.

That’s interesting about Lager breweries still retaining coolers. I guess if they were placed in a closed room, much of the risk of infection with wild yeast was removed. Though the operational coolers I’ve seen in Germany weren’t housed this way. They were just parked next to the copper. Unlike the open fermenters, which were in sealed, refrigerated rooms.

“A receiver is only an intermediate vessel between the hop-back and the refrigerator, and it does not act as a cooler, since it is usually a fairly deep vessel. It must be of sufficient capacity to ensure a regular flow and delivery of wort to the refrigerator. If a spreader in the shape of a dished circular metal plate is fixed at the mouth of the inlet pipe, a certain amount of hot aeration may be effected at this point. Alternatively, the same result may be obtained by discharging at the delivery end into a trough of perforated copper which splits up the wort. This hot aeration is most beneficial towards the subsequent fermentation. Adequate aeration can however usually be effected at the hot end of the refrigerators.”
"Brewing Theory and Practice" by E. J. Jeffery, 1956, page 48.

Hot-side aeration - isn’t that one of the things home brewers go on about endlessly? About how bad it is. While professional brewers have spoken to say that’s bollocks. I see Jefferey is firmly in the pro hot-side aeration camp.

Not sure what will come next. Maybe fermenters.

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

We’re looking at the cooling end of the brewing operation this time. It’s so exciting. I can barely stop myself from weeing my pants.

Remember that we’d got as far as wort receiver. This is what came below that:

“Directly below, again, will be the refrigerators. In an up-to-date brewery, these will almost certainly be of the totally enclosed type. Where refrigerators of the older, open type are used they should be housed in a completely enclosed room supplied with purified air. Means will have to be provided, in these cases, for getting rid of the steam.”
"Brewing Theory and Practice" by E. J. Jeffery, 1956, page 23.

In old-style refrigerators the wort flowed over the top of the cooling pipes, totally exposed to the air. That’s why Jeffery recommends placing them in a sealed room with the air flow controlled. Otherwise there would be a risk of infection.

It seems that back before WW I, brewers relied on high ABV and high hopping to quite a degree. Doubtless they had to tidy up their practices after gravity and hopping rates fell because of the war. I can imagine that the transition was a difficult one.

Here’s an explanation of how cooler and refrigerator worked in tandem to cool the wort to pitching temperature.

“A word of explanation may be added here as to the terms 'cooler' and 'refrigerator' as used in a brewery. The old type of shallow vessel into which the wort was discharged from the hop-back, was called the 'cooler'; in it the wort cooled from the nearly boiling temperature (say 180°-190° F.) at which it left the hop-back, to a moderate temperature, say 120°-140º F. The wort was cooled here simply by loss of heat to the air and to the vessel. The wort then passed to the 'refrigerator' by which it was cooled by water to the required final temperature of 60ºF. This piece of plant, therefore, is not what is popularly understood, as a refrigerator. With the elimination of the open 'cooler' the 'refrigerator' is responsible for the whole cooling operation.”
"Brewing Theory and Practice" by E. J. Jeffery, 1956, page 23.

Remember the word is “cooler” not “coolship”. And that a refrigerator in a brewery isn’t a fridge.
I love the detail with which Jeffery describes the fermenting equipment:

“Finally come the fermenting vessels and racking backs.”
"Brewing Theory and Practice" by E. J. Jeffery, 1956, page 23.

Next time it will be more ranting about coolers.

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.

Brewing equipment 1815 - 1850

I've told you plenty about ingredienst and brewing techniques. Now it's time to take a look at the equipment they used. New developments such as mashing machines and refrigerators were starting to give larger breweries a distinct advantage over their smaller competitors and domestic brewers. They enabled big brewers to brew more quickly, more efficiently, in any weather and to have a much greater degree of control over the fermentation process.


Brewing equipment
That they weren't keen on a wood taste getting into the beer is clear. This is how wood used in the construction of vessels was treated: "English or Hamburgh oak, and Dantzic deal, ought to be seasoned twelve months at least previous to manufacture; subesequently undergo a thorough seasoning of salt, quick lime, and boiling liquor; and, finally, of malt dust, spent hops, and boiling liquor, that it may imbibe as little of the taste of the new timber as possible." (Source: "The Art of Brewing and Fermenting" by John Levesque, 1836, page 9.)

The following equipment could be found in a modern brewery of the period.

Liquor-back. Made of cast-iron and situated in the roof of the brewery. A capacity of at least 10 barrels per quarter of malt used in a brew was recommended. An exposed position was not a disadvantage: "let the liquor come from whatever source it may, it will certainly be much improved by being exposed to the sun and air"(Source: "The Art of Brewing and Fermenting" by John Levesque, 1836, page 7.)

Copper. There were two basic types: open and domed. Thet were made from thick copper and were twice as wide as they were deep. Often breweries had two coppers: the liquor copper, used to heat the water for mashing and the boiling-off which was used for boiling wort. The liquor copper needed a capacity of 3 barrels for every quarter of malt mashed, the boiling-off copper two barrels per quarter. (Source: "The Art of Brewing and Fermenting" by John Levesque, 1836, page 8.)

Mash tun. It was constructed, like a barrel, from wooden staves bound by iron hoops. The staves were two inches thick and made of oak, the bottom of two inch Dantzic deal. Oak was not suitable for the bottom of the tun as it would be warped by the hot water used for mashing. There was false bottom made of cast-iron and four or five taps with a two-inch bore above the underback. (Source: "The Art of Brewing and Fermenting" by John Levesque, 1836, page 9.)

Sparger. This was in common use in Scottish breweries and had already spread to England. It consisted of a horizontal tube with holes along its whole length. It was suspended above the mash tun and rotated about a central axis. A tube, connected to the water supply, was fastened to it. The holes were positioned so that the water came out of them horizontally and propelled the tube around its axis. In this way it automatically distributed the water equally over the whole surface of the grains. (Source: "The Theory and Practice of Brewing" by W.L. Tizard, London, 1846, pages 184-185.)

Underback. This was also made of oak with a Dantzic deal bottom. (Source: "The Art of Brewing and Fermenting" by John Levesque, 1836, page 9.)

Hop-back. Square and constructed of Dantzic deal with a cast-iron bottom. (Source: "The Art of Brewing and Fermenting" by John Levesque, 1836, page 10.)

Coolers. Made from Dantzic deal, with 6-inch deep sides and placed at a slight angle to help drain off the wort. The wood was given a smooth finish to minimise places for dirt to accumulate. (Source: "The Art of Brewing and Fermenting" by John Levesque, 1836, page 10.)

Refrigerator. If used, only half the number of coolers were needed. (Source: "The Art of Brewing and Fermenting" by John Levesque, 1836, page 10.)

Gyle tuns. Made from 3-inch English oak. One type was square. Another was round, airtight and fitted with a safety valve to allow excess CO2 to escape. (Source: "The Art of Brewing and Fermenting" by John Levesque, 1836, page 10.)

Attemperators. Pipes fitted inside gyle tuns through which cold water was passed to control the temperature of the wort. It was attemperotor and refrigerators that allowed large breweries to brew all year.

Cleansing casks. Rather than putting retail casks on stillions for cleansing, special cleansing casks, holding around six barrels were sometimes used. (Source: "The Art of Brewing and Fermenting" by John Levesque, 1836, page 11.)

Stillions. "Stillions are to be built three inch Dantzic deal, a whole plank in depth, bottom one inch and half, and about two inches wider at the top than at bottom, which ought to be for barrels 18 inches wide, 21 inches for hogsheads, 24 inches for puncheons, and so on in proportion for larger or smaller casks: the widths here recommended ar favourable to filling up witth clean beer, and to contain the yeast; a side plug-hole is necessary to draw off the beer, bored with a taper bit; the hole inside to be within about three quarters of an inch of the sole edge or bottom, to keep back the yeast; another hole of 3 inches in the bottom, to get the yeast out; and the stillion laid to a current of one inch to ten feet." (Source: "The Art of Brewing and Fermenting" by John Levesque, 1836, page 11.)

Settling back. A shallow vessel, six inches deep, in which beer from the stillions was left to clear before being used to top up the cleansing casks. (Source: "The Art of Brewing and Fermenting" by John Levesque, 1836, page 11.)

Vats. Made from 1.5 to 2 inch English oak. Vats of various sizes were needed for a variety of purposes: ageing strong Ale and Stout, blending worts from different brews, or mixing worts of different quality. They varied in size between the volume of one and three brews. Vats could be filled several times without cleaning out the lees, especially with Porter or Stout. (Source: "The Art of Brewing and Fermenting" by John Levesque, 1836, pages 11-12.)

Casks were cleaned by filling with boiling water and being left to stand for 15 minutes, rolling occasionally. At the end of the process they were rinsed with cold water and left, without bungs, to dry. (Source: "The Art of Brewing and Fermenting" by John Levesque, 1836, pages 12-13.)

Rake mashing machine
The first type of mashing machine, invented 1807, was the rake masher. It replaced men working with oars to mix the malt and water. Not only did it save on labours costs, it also mixed more quickly and more thoroughly, helping increase the efficiency of the mash. (Source: "The Art of Brewing and Fermenting" by John Levesque, 1836, pages 39.)