Dry hopping and a visit to Lupofresh

Dry hopping, the traditional British technique that was invented in America in 2007, is all the rage now. So it was with interest that I went to Lupofresh to hear a lecture from Russell Falconer of Hopsteiner on it. Shame I didn't get to the IBD Asia Pacific conference as there were six lectures son it there.

Dry hopping, adding hops to beer after (or even during) fermentation, is the best way of getting hop aroma into beer.

Where hops are added to the beer has a strong influence on how they affect the flavour. With dry hopping there's heat so the essential oils aren't driven off so remain in the beer. Rates have risen from a modest 20g/hl up to 1000!

The oil content of hops varies from year to year by up to a factor of two and doesn't show much correlation with alpha acid content.

Various methods are made to add different types of hops at different stages.

Whole hops, type 100 pellets (hop plugs), hop pellets, in a bag or loose.

Adding dry hops loose gives more flavour than in a bag.

More oil is extracted over time but it can also add negative characteristics (vegetal flavours)

Separate dissolving tanks which the beer is recirculated through are becoming more common now. Dissolving hop pellets warm gives better results for the first 24-48 hours but after that point the results are the same as if the dissolving beer was cold. Some new systems can get the flavour out in four hours.

It can be used in conjunction with the Iso-Mix system (which re-circulates beer through a submerged jet head) or GEA hopstar which has a perforated up pipe.

It's possible to drop pellets out a cyclindro-conical fermenting vessel and then crop yeast later. Dry hopping will cause beer losses as they can swell up to size times the size they are when added.

Hopsteiner have developed a "beer cleaner" with a 250μl sieve for separating beer from hop debris.

Losses can be reduced by using lupulin powder (made in a similar manner to Type 45 pellets so luplin glands are concentrated and "leaf" matter reduced) or you could add hop oils.

Despite the lack of boiling (so no isomerisation of alpha acids) dry hopping will still increase bitterness.

There are changes during fermentation due to adsorption, interaction with products of fermentation and biotransformation.

And just when I'd decided the only important thing about fermenter geometry was height and the associated difference in hydrostatic pressure it turns out there's more to it. Greater the surface area at the top of the tank the greater the amount of volatiles lost.

In large tanks there will be different concentration of hop flavour volatiles in different parts of the tank so mixing ins better.

Filtration will remove flavour compounds, but some more than others. Myrcene (grassy/estery) is mostly removed by fruity notes tend to go through the filter.

Storage trials of beer stored cold and warm (c/w) showed marked reduction of most hop oils

Mixing and amount of contact are more important when dry hopping than temperature (though yeast interactions will be affected by temperature).

In the discussion that followed there were a few more juicy titbits. Fullers pick up 6 IBU (by analysis) cold dry hopping, which will come from oxidised products not isomerisation.

There is an optimum length of time for dry hopping so dry hopping in tank gives a more stable product.

Dry hopping increases the beer pH so there can be an increase of 2-3 IBUs due to this.

Sadly the speaker could shed no further light on the diaststic effect of dry hops but Horace Brown mentioned it in his wonderful reminiscences and more than a century after Brown's work there's a podcast about it from the MBAA here.

And then we had a tour of Lupofresh/Morris Hanbury.

It wasn't quite like when I went round a hop processing plant in Germany, which no doubt reflects on the relative successes of the British and German hop industries.

Type 90 pellets are made by hops going to the bale breaker, they may then be subject to further drying before going to a hammer mill before mixing, cooling, pelleting and packaging.

Anyone else remember Reanimator?

Proper science coming up:

Morris Hanbuy make Type 90 and Type 100 pellets, Isomerised Kettle Extract, Iso-alpha extra and reduced Tetra extract with the hydrogenation carried out in house using a novel process.

Confused about CAMRA

Now the votes on CAMRA's revitalisation process are in beer geeks have reacted in the only way they know: by saying what they always say. A volley of rattles have been thrown from the prams of crafties, accompanied by the usual abuse they think it's OK to heap on people they assume are old. And on the other side those opposed to change are happy CAMRA has stayed true to it's original aim. Apart from one loonspud who's delighted a Commnunist conspiracy has been defeated. 

But I really don't think the results are at all as clear cut as that. All but one of the resolutions to change CAMRA's constitution passed, including what I would have thought would make the crafties happy:

"To play a leading role in the provision of information, education and training to all those with an interest in beer, cider and perry of any type"

Surely that's widening CAMRA's remit to include craft beer?

The proposals that failed to pass looks to me that it's actually about defending pubs and acting as the de facto beer consumers' organisation in Britain:

"To act as the voice and represent the interests of all pub goers and beer, cider and perry drinkers"

Why this not going through has caused so much outrage amongst crafties is a mystery to me, but I have seen a couple say it was the only important point in all the revitalisation proposals. For a long time CAMRA has been focused on defending pubs and has acted as the de facto beer consumers' organisation in Britain and I can't see that changing.

I know I'm not the only person a bit bemused by the reaction on twitter (shout out to @jwestjourno and @desdemoor !) but it does feel like fact are far less important than preconceived ideas on the internet. Mind you, that's not exactly new!

Bollocks from The Guardian

Brewers and beer geeks across Britain have been bemused by The Guardian producing an impressively incomprehensible article about brewing. Now anyone can make mistakes and brewing can get technical at times, but the author clearly has absolutely no idea what they're talking about.

Global brewery AB InBev a patented a new system for saving energy when brewing by stripping unwanted volatile compounds from the wort (unfermented beer) by bubbling inert gas through it rather than using a vigorous boil.

Bizarrely though The Grauniad starts with a headline talking about putting fizz in beer and then goes on to talk about malting and fermentation:

"The Belgium-based company AB InBev says it has developed a technique to generate gas bubbles needed for the malting of grains before fermentation without the need to boil the water and hops."

The process has nothing to do with malting, fermentation or fizz in beer so it's not surprising that so many people have been confused. If you're keen to know more about what's really going on there's some brief information about the project here and more details in the patent here.

If you thought dad dancing breweries were bad...

...check out the dad dancing maltster trying to go "craft".

I really don't know what to make of it, but nautical themed cartoons aren't what I look for when I'm after malt. I don't need each malt type to be given a themed brand either, but UK figures for the malt analyses would be nice.

Paul's Malt were once a big British maltster, before being sold to Irish agricultural company Greencore who sold them on again to multi-national malting company Boortmalt. Reviving the Paul's brand looks like how they're hoping to sell to craft brewers. That and nautical themed cartoons obviously.

Still, as Paul's Malt has been revived how about reviving the Paul's Brewing Room Book? It contained a lot of useful information which would be handy for craft brewers.