Thursday, 7 May 2009

A master brewer


The last post was about grain provenance. In some weird coincidence, which seems to happen to me a lot, one of the master brewers from one of the major breweries checked in to stay last night. He doesn't want to be named or have his brewery named, which is understandable. Irrespective of the fact that I could see his company as part of the homogenisation of the general public attitude to drinks products, he is, none the less, a brewer. As we were both enjoying a drink in the bar we naturally got talking about brewing and comparing the various brewing processes that are used.

We talked about mash filters and mash tuns and high gravity brewing before liquoring back to the finished products. We talked about the fact that with modern mash filters efficiencies of 110% can be achieved. Now how can that be the case? Well, theoretical maximum conversion is determined by laboratory mash process, where sparge is continued until a volume of liquid with a overall S.G. of 1.001 is achieved. This is still not as efficient as milling the grain very fine, using membranes instead of wedge wire strainers and then squeezing out the grain. Hence a practical extract that is better than the theoretical maximum. Magic eh?

We talked about that fact that most major brewers add sugar of some sort and also use hop extract liquids to fine adjust the hop profile. I could not argue that most technical developments in the brewing industry have come about as a result of cost driven research. For instance, trading off sparge time against the number of brews per day might cost £100,000 per year in sugar costs, but might result in 2 more brews per day, and hence more product throughput and more profit.

Lagering time has been reduced by careful experimentation with the yeast and how it behaves in various situations. Using a faster more efficient process to provide a product that the consumer cannot distinguish from a slower less efficient method begs the question; why less efficient methods should be used? If real hops are needed then they are used. Even using aroma hops in some cases because there is just no other way of getting the result. This is a similar argument to the Maris Otter conundrum I posed in the last post.

None of this was really a surprise to me, but was interesting none the less.

What got really interesting was when we started to discuss quality. Now you might think that macro brewed beer is generally nondescript. I would of course agree. But it's consistent. It's very, very consistent. This particular brewer was very keen to stress that his team took great pride in getting as close as possible to the target parameters. Tasting is done at the wort stage, during fermentation and during conditioning, at the point of packaging and then samples held back for further tasting and testing afterwards.

In fact he was quite insistent saying "It really annoys me when people say that the big brewers don't care about quality, we do care, very much". Certainly if this brewers attitude is anything to go by, the people on the brew lines really do care.

I still don't drink his products and would not stock them, but that's not really the point.

11 comments:

Velky Al said...

I met up with a brewer from England recently in Prague and had some fascinating and informative conversations - it is an experience I recommend to anyone who loves beer and wants to understand the ins and outs of it all.

Tandleman said...

"the target parameters". That's where it goes wrong. It may well be a "quality" product by meeting a technically difficult spec, but subjectively, is it one you'd want to drink?

Jeff Pickthall said...

An age-old conundrum - how do you define "quality"?

Artist formerly known as Wurst, CEO APRK said...

"Well, theoretical maximum conversion is determined by laboratory mash process, where sparge is continued until a volume of liquid with a overall S.G. of 1.001 is achieved."

Dave, are you sure 1.001 is correct? 1.000 is water.

Woolpack Dave said...

Yes, well, I was told on a Quality Assurance course, that I was forced to go on in a previous life, that quality is just a measure of parameters. The parameters can be set deliberately to produce what you and I would class as a low quality product.

Is it better to have consistent quality or better quality that varies a bit? Your choice I guess.

None of that undermines the guys enthusiasm for brewing though. Plus, I suspect he makes a damn site more money than me a year.

Woolpack Dave said...

Wurst, look at this technical page

Woolpack Dave said...

or is it "damn sight"? - not sure....

Woolpack Dave said...

or perhaps "dam sight" - now I've really confused myself.

Tandleman said...

damn sight I reckon. A colloquial term

Artist formerly known as Wurst, CEO APRK said...

Ok, I think I got it. It's basically an equation that explains 85% mash efficiency. I batch sparge and only get 63%, which is ok. It's consistently 63%, so I can dial in pretty much any recipe.

"A value of 300 l°/Kg indicates that 300 litres of wort, OG 1001, would be produced from each Kg - or say, 300 ÷ 40 = 7·5 litres of wort, OG 1040." This is complicated way(maybe not if you're a huge brewery) of explaining mash efficiency.

Woolpack Dave said...

Wurst, I think that is how the Lab actually do it. Wash through with so much water they have to have got out all the sugars, but of coarse results in a very weak sugar solution. Highly efficient but there will always still be something more that can be got out of the grain.

63% is OK for sure. In the early days I had some lower than that. I now look for more like 75-80% efficiency. I wouldn't get too hung up on actual efficiency unless you are doing it commercially.