Meeting

Details

Chris White, founder of White Labs, took time out from a conference to address a packed and attentive audience at McCowans Brewhouse, Edinburgh on 20^th September 2005. As his talk in England had to be cancelled due to lack of interest, your scribe was delighted to have the opportunity to meet him and indeed the Scottish Craft Brewers in the UK’s brewing (if not real ale) capital.

Chris White studied Biochemistry at UC Davies where he took some classes at the Brewing School out of interest. His interest deepened and he went to San Diego to do postgraduate work on yeast in 1991. He then set up White Labs in San Diego in 1995 in a small (90m²) facility which was outgrown by 1998 and they moved to larger premises. During this period he was a keen home brewer and while his interest has been maintained, the success of White Labs means that he gets to brew rather less often.

Most of White Labs’ production now goes to US microbreweries, typically producing 5000 - 10 000 bbl/pa. Note that corresponds to a brewlength of 50 bbl – contrast with British micros where length is more like 5-30 bbl. (1 bbl = 1 brewer’s barrel = 0.7 UK barrels = 1.2 hl).

Production is very different to a dried yeast plant - typically fifty strains (out of 400 in the ‘fridge’ at ‑70 to ‑80C) will be produced each week. About 30% of production is of ‘private’ strains. Most of production is lager yeast and during the vintage 50% is wine yeast. However Chris’s heart is clearly in his ales, as we’ll see later.

Microbiology

The history of microbiology was, for the first few centuries, that of scientific brewing. In 1680, Antonie van Leeuwenhoek, the pioneer of microscopy first observed “little animalcules” in beer. The significance of these was not fully appreciated until Pasteur (the last Frenchman to teach us anything about brewing - Ed) demonstrated that wort would not ferment unless inoculated with yeast around 1850. This was news! Brewers now realised that cleanliness was key to sound beer production, at least those who stayed in business did. Pasteur was without honour in his home country where small breweries fell by the wayside conspicuously earlier than they did elsewhere.

Beer demands sterility

Chris stated that the quality demands for brewing yeast are far higher than that for bread - the destination of most yeast produced - as it is only used for one cycle, as is distillers’ yeast. Even wine requires less purity as other flavour elements disguise the characteristics of the yeast.

A characteristic of brewing yeasts is that they do not produce phenolic off flavours (POFs) and are thus known as POF-negative. Chris pointed out that all wild yeasts are POF-positive and thus brewing strains have been created by mutation and selection by brewers. Now those who have suffered phenols in their beer might wonder who would want a POF-positive strain. Wine makers, it would seem. The flavours in some wines at least overpower the POFs and some wine flavours benefit from wild yeast “contamination”.

While brewers started using single strains following Hansen’s development of single-cell techniques at Carlsberg around 1880, they were first used for wine production in the 1920s. (Wine producers are still strangely reticent about their yeasts, allowing punters to romantically imagine that the yeast comes from the grape skins - Ed.}

Anyway, propagation has to be sterile. This is not a quick squirt of sodium metabisulphite - this involves man-sized autoclaves and clean rooms. The results aim to achieve less that 1 bug in 10⁹ cells; Chris reckons that the best dried yeast will achieve 1 in 10⁷. For comparison, your scribe seldom counts yeast in his brewery without spotting something suspicious swimming about by the time he has counted 100 cells, so there’s little reason for a home brewer to choose liquid yeast for sterility alone - the benefits are in flavour.

Yeast performance

Chris listed a range of reasons for yeast death, taken from Walker’s 1998 research at Dundee. We select a couple of points from this. Firstly yeast can be killed by shear forces when being pumped. However this should not be a problem for those using magnetic stirrers at a modest swirl, which is sufficient to aereate the wort and clear the evolved CO₂. On CO₂, Chris reckons that a small amount of dissolved CO₂ in a fermentation will seriously reduce yeast performance. Even the small partial pressure of CO₂ built up under an airlock will have an effect. He recommends racking or rousing to clear CO₂ and introduce some oxygen to ensure complete fermentation. Now this is similar the “dropping” method practised by Brakspear’s and once advocated by Graham Wheeler. However dropping is often advocated after about 36 hours of fermentation. Chris is suggesting a bit later, but while there is still enough yeast around to mop up the oxygen avoiding oxidation. He cited Sierra Nevada who transfer at 1020, although acknowledges that few breweries do this.

Un-American activities?

Chris compared the US and UK brewing traditions and described the US as having no middle ground; beer tends to be either anonymous swill from the big boys or aggressively hopped and strong from the micros. US brewers, he reckons are not very interested in flavours created by yeast, sticking to four or five ‘boring’ strains. Indeed he noted that the traditionalists in this regard were Anheuser-Busch and Coors who stick with their traditional strains which have flavour and flocculation characteristics that would not recommend them to new brewers.

He praised the British for taking more of an interest in highly-flavoured, low strength ales and making the most of yeast-derived flavours; White Labs use gas chromatography analysis of head space for fusels and esters to characterise their yeast. He advocates open fermenters for flavour and was greatly relieved to discover that the Scottish Craft Brewers practice was open fermentation. US brewers use sealed fermenters because they are much easier to clean with cleaning in place (CIP) systems and small amounts of aggressive chemicals

He felt that closed fermentation practised in the US leads to greater concentration of undesirable volatiles in the beer; hence US some craft brewers characterise their Trappist yeast as “bubblegum” and prefer the Abbey strain. These two yeasts will perform closer to type in open - or at least shallower - fermentation systems. The ideal system he believes is open fermentation, in a clean room. A quote: “I love open fermentation. I try to talk US homebrewers into it. It gives different volatiles and fermentation is faster because the yeast is healthier.”

Chris also commented that while the Czech brewer Budweiser Budvar has clung to its traditional yeast they did not appear to give any thought to the change in its performance when they went from wooden fermenters to stainless cylindroconicals. One seldom hears Americans saying how much better things were under the communists and can only hope that Senator McCarthy does not read this journal.

Using yeast

The audience was surprised to hear that the yeast can remove a considerable amount of the hop character from a beer if it overflows the fermenter or is skimmed; it might be necessary to double hopping rates to account for this. The number of times a yeast can be re-pitched depends on the cleanliness; Chris reckons 2-3 times at home and ten times commercially. Home brewers should be aware of the contamination in domestic kitches and take appropriate care. Top-cropped yeast is healthier. He states that yeast recovered from bottle-conditioned beer is rarely very good due to stress – but “he would say that, wouldn’t he”!

Chris reckons that a single tube is sufficient to ferment 20 litres of ale wort, without a starter. The brewers present generally preferred a starter, and he conceded that there was nothing wrong with that, but stated that during the short periods mentioned (12-24h) the main effect was to wake the yeast up – little cell multiplication would occur. The White Labs tubes contain around 100 billion cells, equivalent to a ‘pint starter’. (This is about a quarter of the amount in an 11-g pack of Nottingham Ale yeast. (The White Labs tube gives a pitching rate of 5 million cells/ml into 20 litres. Recommended commercial pitching rates for ale are 1 million per degree Plato (ie 4 brewers degrees). It’s up to the brewer whether to increase the amount of yeast in a starter or in the fermenter – clearly many US brewers produce prizewinning ales just pitcing straight – Ed). Chris suggests aereating the wort for 30 minutes.

Temperature control is key to a successful fermentation. The character of Belgian ales in particular is determined by yeasts and fermentation temperature. To retain esters (fruitiness), Chris suggests reducing the temperature of a fermentation towards the end as the flavours are developed in the first 72 hours. It is also wise to remove the green beer to a closed fermenter towards the end to reduce the risk of infection.

Lager requires a lot more yeast – four vials might be required. He suggests a starter or, as the substrates for ester formation are not present in the first 12 hours of fermentation, the fermentation could be started at 21°C. This allows yeast to multiply and the fermentation is then  cooled to lager temperatures – say 13°C. He concedes that this opinion is not universally held. Similarly ales could be started at 21-24°C – even as high as 27 so long as it is cooled within 12-24h.

One final tip for those who have opened a vial and been sprayed by yeast. Crack the top open as soon as the vial is removed from the fridge and continue to release gas every hour or so until pitching.

Notes on specific strains

WLP002 has very high flocculation and will in consequence pull out a lot of hop character from the beer. The Edinburgh strain WLP028 in contrast is less flocculent, preserving hop character.

The high-gravity yeast WLP099 does not ferment maltotriose. In consequence to get very high alcohol content it is necessary to use an enzyme. Home brewers are reluctant to do this as the substance persists in the product potentially leading to bottle bombs. With high-alcohol beers (around 20%) this is not a problem as the alcohol will stop the yeast.

The German lager yeast WLP830 is now their top seller (after WLP001 “Chico”) although it is less popular in home brewing circles. It is exported to Japan, Brazil, Taiwan – and indeed back to Germany.

And so, back to the Waverley for the sleeper back to London. Haggis and neeps, Traquair ale and Lagavulin in the lounge car provided a fitting end to a delightful evening. Many thanks to Chris White for his time and openness, John Braithwaite of the Hop & Grape (White Labs UK distributor) for coming north and and providing samples and of course the Scots for organising the event.

Scottish Traditional Beer Festival

Assembly Rooms, Edinburgh.

Report by Bill Cooper

Saturday 16^th April was the day of the long awaited return visit of the Northern Craft Brewers to the “Macbrewers” as they call us. For some of us the visit was spread over three days. Friday evening saw the first group of the northern lads arriving and a pub crawl gradually developed as new arrivals came on board. We started at Cloisters Bar, moved on to the Blue Blazer, and then to the renowned Bow Bar in Victoria Street, where Deuchars I.P.A. first saw the light of day. Friday night in central Edinburgh is not ideal for finding quiet pubs for a re-union chat, standing room only in some in fact, and by this time the party was beginning to fragment. We ended up, or some of us did, at the Halfway House, Camra’s Edinburgh “pub of the year”. Half way because it is said to be half way between the Waverley Station and the Royal Mile. Or in my view, half way up or down a long flight of stone steps. We ended here because they were apparently prepared to stay open as long as we were drinking whereas our next proposed port of call was shutting at midnight. I assume everyone got back to their beds safely as we all met up again at one o’clock on Saturday at the Caledonian Brewery.

The brewery tour was divided into three groups, a “history” tour for those less interested in the brewing process, and two “technical” tours. The one conducted by Robert Burton, head brewer, was quite forthcoming about Caledonian “secrets” and will be reported elsewhere by David Edge.

The rest of the afternoon mixed conviviality with serious presentations. The beers, in ample supply, were in good condition. It was not really an occasion for taking notes as you will no doubt perceive. Stephen Crawley, Managing Director of Caledonian Brewery, told us about the physical developments to the site made necessary to accommodate the brews being taken on from Scottish Courage.  (Already it is asserted that McEwans 80/- is showing signs of improvement).  Stephen was confident that the normal range of Caledonian beers would go from strength to strength and would penetrate further into the English realm in the not too distant future. Looking ahead ten years he was sure Caledonian brewery would still be thriving and not be swamped by being part of a mega brewing conglomerate.

A more amazing story came from Steve Taylor, founder of Northern Craft Brewers, who was persuaded by Bill Lowe, one of their eminent beer judge members, that his home brewed beers were worthy of wider consumption. He evolved the concept of the Copper Dragon Brewery at Skipton, based on meticulous planning over a period of two years, state of the art equipment from Germany and some “Rolls Royce” embellishments from his experience in working to their exacting standards designing tools for making aero engine components. To operate all this he recruited a master brewer from the now defunct Websters Brewery, and within twelve months the 10 barrel plant was unable to meet demand.  It is now quadrupled in size, and using a direct sales force and not relying on agents, is making inroads into the markets of such revered brands as Landlord and Black Sheep.  It is indeed a serious success story but not possible without very substantial capital resources and a great deal of confidence and courage on Steve’s part. Well done Steve.

John McGarva showed us the opposite end of the scale, and perhaps one more within our comprehension, in creating a commercial brewery on a relative shoestring. John also showed courage in using redundancy from his day job as a spring board to set up the Tryst Brewery on an out of the way site near Falkirk. Brewing takes up only a small part John’s week although he produces 4 different beers, as he is virtually a one-man band with occasional help from relatives. Much of his time is spent seeking sales outlets and then delivering beer. Nevertheless his beers are well appreciated and we wish John every success in his venture. 

It was delightful to renew acquaintance with old friends from the north of England and to welcome David and Janette Edge from Midlands Craft Brewers. The event would not have been complete without the very welcome presence of James "Dougall" McCrorie the CBA founder. We were also delighted to see so many of our own members and especially those like Charlie Clark and Andrew Warwick who can rarely make it to our meetings.

We all, or nearly all, re-assembled in the evening at McCowans brew pub, close to the site of the Fountainbridge Brewery of Scottish Courage, soon to be no more, for dinner. The pub made us very welcome and were happy to let us drink, free of charge, three firkins of beer supplied by Steve Taylor and John McGarva, our commercial brewers, plus the winner of the Scottish Homebrew competition, brewed by Aled Murphy only 8 days previously at the Bridge of Allan brewery. Thank you all three. The food was ample and inexpensive, there were no formalities, and after the meal we all repaired to the main bar where conviviality continued until after I departed for my bed.

On Sunday James (Dougall) McCrorie, Pam and I met David and Janette Edge for lunch at the Halfway House,  handy for David and Janette’s train journey home to Derby. Can’t say I remember much about the conversation but I am sure it must have been scintillating.  Finally my thanks to Pam for selflessly acting as chauffeur.

Calton Centre

We had approximately 15 new brewers attend the meeting, which is mainly due to our recruitment sergeant Dave Martin who owns Edinburgh’s finest Home Brew Emporium, (cheque should be in the post for that one) and tells any customers who care to listen of our organization and its aims.

Our day started at 10am with some of the more mundane brewing preparations taking place, cleaning, sterilization and boiling of water. I should at this point mention the team responsible for the brew, Les Howarth was MC for the day, explaining what was going on and fielding questions, Ian McManus and myself, Kenny Mowbray, were doing the donkey work i.e. making the brew.

The equipment used to make the brew came from the committee members and we endeavoured to bring along the simplest equipment we could, thus showing the newer members how easy it all is.

The recipe was one of Les’s and again this was kept as simple as possible.

Interspersed with the mash we had a yeast trial which meant there was plenty of beer brought along by our members to sample, this also avoided people standing about waiting for the next stage to begin.

Throughout the day we demonstrated the various aspects required to make beer which I’m sure you are all aware of, so I will not bore you with the details, this generated many questions and discussions, not only from the newer members but also from our existing and highly experienced members, resulting in a lively and highly entertaining day, comparisons between methods of performing every stage of the brewing process were discussed with the most common phrases being “you do it that way I had not thought of that” or “ that’s a good idea I must try that” or “ NO NO NO do it this way” or  “that’s a handy piece of  kit, where did you get that from”

The entire process took approximately 5 hours with the wort being retained, fermented and hopefully at our next meeting the resulting beer will be available for those present to sample.

The newer members had the benefit of their questions and queries being answered by more experienced brewers and said they found the day “educational and helpful”

So the day went well with everyone enjoying themselves and I would recommend it  to others interested in brewing as a great icebreaker and hopefully we have attracted a few more members into the bargain.

slainte