Monthly Archives: May 2013

Homebrew: Imperial Stout

It’s always a good idea to think ahead, especially when brewing beer, as many styles require several months (even up to a year) of maturing, before they reach their prime. This is especially the case with darker beers and/or beers with a high alcohol content. During maturation, hot and alcoholic tones typically decrease, astringent roasted tones typically become milder, and the flavours as a whole typically blend together better. So what I’m trying to introduce with this post is our next brewday (hopefully tomorrow), during which we will brew an Imperial Stout for next winter. By brewing it now, it will have around 6 months to mature before the first snow falls (hopefully).

The recipe will be pretty much based on the Black Panther Imperial Stout I brewed up in November 2011. Only this time we are brewing up a normal size batch (20 liters) and hopefully won’t have to add any DME to get to the correct original gravity.

[codebox 1]

 

Brewday: Imperial IPA

Today we brewed the Imperial IPA mentioned in the previous post, and also tried out a new mashing strategy. We have previously been doing single-vessel mashing with our brew kettle, most recently using BIAB-bags. The problem with the bags is that large amounts of flour, grain debris and protein end up in the boil, and our wort is always very cloudy. It’s also a huge hassle to lift out the heavy bags, and squeeze out any liquid out of them. So for today’s brewday, we started reusing my old cooler mash tun, and mashed by keeping the grain in the cooler and recirculating the wort via the kettle (basically a Brutus 20 design). In the beginning we had to play with the valves to keep flow levels into and out of the mash tun equal, but in the end I must say I’m really pleased with how the mashing went. The temperatures were more stable, probably because of the increased insulation of the cooler, and the wort that ended up in the boil kettle was crystal clear (which meant much less trub at the end of the boil). We also didn’t have to lift and squeeze out any heavy and warm grain bags, and we ended up hitting all our numbers exactly! Will definitely continue doing two-vessel mashes. Anyways, we ended up with 20 liters of 1.087-strength wort, that was both bitter and hoppy. Hopefully fermentation goes well and we end up with some tasty IIPA for the summer!

Homebrew: Imperial IPA

I brewed an Imperial IPA about a year ago using 500 g of hops (for 20 liters) and 5 different hop varieties. I was quite happy with how it turned out, but it was maybe a bit muddled, slightly grassy and it could have been slightly drier. This year (on Sunday) its time to brew another Imperial IPA, and I will try reducing the hop amounts somewhat, and producing most of the bitterness using hop extract. The kettle hops will be Cascade, Centennial and Columbus, and for the dry hops Amarillo and Simcoe will be added as well. I’m going to ferment the beer using my new favorite yeast, WLP002, and will mash low to make sure the beer doesn’t finish too sweet. Here is the recipe:

 

[codebox 1]

Article on the physiology and fermentation performance of various lager yeast strains and Saccharomyces eubayanus

An article on the physiology and fermentation performance of various lager yeast strains and Saccharoyces eubayanus that I co-authored has been accepted for publication in the Yeast journal and the article was just released online. We found that the fermentation performance of Frohberg strains in wort were superior to that of Saaz strains and S. eubayanus, but the Saaz strains and S. eubayanus were the least sensitive to cold (growth at 10 °C). Surprisingly, it was found that fermentation performance of  S. eubayanus was limited by the inability to take up maltotriose. This explains the poor attenuation levels I also saw in my S. eubayanus homebrew. Here is the abstract:

Two distinct genetic groups (Saaz and Frohberg) exist within the hybrid Saccharomyces pastorianus (S. cerevisiae x S. eubayanus) taxon. However, physiological/technological differences that exist between the two groups are not known. Fermentative capability of the parental S. eubayanus has likewise never been studied. Here, 58 lager strains were screened to determine which hybrid group they belonged to, and selected strains were characterized to determine salient characteristics. In 15 °P all-malt wort fermentations at 22 °C, Frohberg strains showed greater growth and superior fermentation (80 % apparent attenuation, 6.5 % alcohol by volume in 3-4 days) compared to all other strains and maintained highest viability values (>93 %). Fermentation with S. eubayanus was poor at the same temperature (33 % apparent attenuation, 2.7 % ABV at 6 days and viability reduced to 75 %). Saaz strains and S. eubayanus were the least sensitive to cold (10 °C), though this did not translate to greater fermentation performance. Fermentation with S. eubayanus was poor at 10 °C but equal or greater to that of the Saaz strains. Performance of Saaz yeast/S. eubayanus was limited by an inability to use wort maltotriose. [14C]- Maltotriose transport assays also showed negligible activity in these strains (≤ 0.5 µmol/min/g dry yeast). Beers from Saaz fermentations were characterized by 2 – 6 fold lower production of the flavour compounds methyl butanol, ethyl acetate and 3-methylbutyl acetate compared to Frohberg strains. Higher alcohol and ester production by S. eubayanus was similar to that of Frohberg strains.

  • Gibson, B.R., Storgårds, E., Krogerus, K., Vidgren, V., (2013) Comparative physiology and fermentation performance of Saaz and Frohberg lager yeast strains and the parental species Saccharomyces eubayanus. Yeast. In Press. DOI: 10.1002/yea.2960

Something different: Homemade Tonic Water

I’m not only a big fan of beer, but I also enjoy well-made long drinks, such as Gin & Tonic and Moscow Mule. Having made my own beer for a couple of years now, I thought it would be interesting to try to ‘brew’ up some soda as well (i.e. tonic water and ginger beer). First up is my attempt to make homemade tonic water. The tonic water I made isn’t actually a fermented beverage, rather it’s a flavor syrup, which is to be blended with club soda to make sparkling tonic water. Tonic water is basically a soft drink containing quinine, and was originally used as a prophylactic against malaria. Other flavorings (and gin) have since been added to mask the highly bitter flavour of quinine. Quinine is found naturally in the bark of cinchona trees, and this was one of the ingredients in the homemade tonic water. I found a couple of recipes online (see here and here), which I then adapted to what I could find in the supermarkets here. The recipe is:

  • 9 dl of tap water
  • 0.5 dl of cut cinchona bark (alternatively in powder form)
  • Juice and zest of 1 lemon
  • Juice and zest of 1 lime
  • Juice and zest of 1 orange
  • 1 cut up lemongrass stalk
  • 22 g of citric acid (found a pouch containing 22 g in the store, this could perhaps be increased looking at other recipes)
  • 1.5 teaspoon of whole all-spice
  • 0.5 teaspoon of kosher salt
  • 1.5 dl of agave syrup

You basically combine all the ingredients except the agave syrup in a stainless steel pot, bring to boil, and let simmer for 20 minutes. After this, you filter away the particulates through a strainer, followed by a coffee filter (this will take some time). After filtration, the mixture is added back into the stainless steel pot (which has been cleaned up) and it is brought back up to boil. The agave syrup is then added, and the ‘tonic water concentrate’ is then poured into a clean flask/container and stored in the refrigerator (I managed to squeeze out about 8 dl of concentrate). To make a Gin & Tonic, you combine 2-4 cl tonic concentrate (this takes some experimentation) and 6 cl gin in a glass with ice, and then top off with club soda.

 

 

The homemade tonic will have a yellow-brownish tint, so it won’t look like a commercial tonic water, but the flavour is awesome!

Small update

My inactivity on the blog seems to be a recurring theme, and this time I’ve been both abroad and busy at work. The brewing of the recipe mentioned in the previous post went quite well, but had a minor hiccup during the mash, when the BIAB-bag scorched slightly against the element. We tasted and evaluated the wort throughout the rest of the brewday, and concluded that we couldn’t detect any burnt or smokey flavors, so hopefully the beer will turn out fine! We ended up with around 21 liters of 1.091 wort instead of the planned 17 liters of ~1.105 wort, which would have required some more boiling, but in retrospect I think a slightly lower OG will do the beer good. We also had some fantastic beers during the evening (Alesmith Speedway Stout, Braufaktum Palor, Brewdog San Diego Scotch Ale, Cervesa Espiga Bruna, Dougall’s Leyenda, Great Divide Chocolate Oak Aged Yeti, Great Divide Espresso Oak Aged Yeti, Great Divide Yeti Imperial Stout, Hopfenstopfer Christmas Ale, Nómada Humala IPA, Poppelmans Nya Världens IPA, Popaire Tinta De Pop, Slottskällan Double IPA, Stone Imperial Russian Stout, Strömsholms Brygghus Gråskägg, Uncommon Golden State Ale, Homebrew Amarillo Hefeweizen, Homebrew Eubayanus Blond, Homebrew BSDA, and Homebrew Black Lodge Imperial Stout). My favorites of the evening were the Yeti trio, with the chocolate-aged being number one, Slottskällans Double IPA and surprisingly the Eubayanus Blond. Today I also transferred the Summer Pale Ale to two kegs, and gravity had fallen from 1.055 to 1.009 giving an ABV of 5.7%. The small taste sample I had was quite earthy and maybe slightly even smokey, but that was most likely because it was from the bottom of the fermenting vessel, containing mostly yeast and dry hop trub. Hopefully the next sample will be better! Right now I’m sipping on a Firestone Walker Double Jack and just enjoying the fact that I’m officially a Master of Science. The beer is simply amazing and will try to brew some kind of clone of it next.

Homebrew: Oak-Aged English Strong Ale

I haven’t brewed many English-style beers during my homebrewing career, mostly because I’m more fond of the flavor profile of new world hops (e.g. Amarillo, Cascade, Citra, Simcoe, etc.) and I like my beers hoppy rather than malty. I do however occasionally enjoy English-style beers (e.g. Fuller’s ESB), so I don’t have anything against them. A friend just flew over from Barcelona, and next week I will be arranging a brewday and beer tasting for him. We decided on brewing a slightly stronger ale, i.e. one that survives several months of aging, since I’m not sure when he will visit next time. I became interested in Firestone Walker’s Double DBA, so we decided on trying to brew something inspired by it. The beer will have a hefty OG (1.100+), moderate bitterness (around 40 IBU), Goldings hops, will be fermented with WLP002, and bulk-aged on oak cubes (most likely bourbon-soaked). I hope WLP002 won’t leave the beer cloyingly sweet, so will mash at 63C (145F) for most of the mash. The recipe will be the following:

[codebox 1]