Suregork Loves Beer

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

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!

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.

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:

Recipe: Oak-Aged English Strong Ale
Style: English Barleywine
TYPE: All Grain

Recipe Specifications
--------------------------
Boil Size: 27.6 l
Post Boil Volume: 22.4 l
Batch Size (fermenter): 17.5 l   
Bottling Volume: 15.5 l
Estimated OG: 1.108 SG
Estimated Color: 33.3 EBC
Estimated IBU: 43.9 IBUs
Brewhouse Efficiency: 55.00 %
Boil Time: 105 Minutes

Ingredients:
------------
Amt          Name                                     Type     #   %/IBU         
7.600 kg     Pale Ale (2-row) (6.0 EBC)               Grain    1   68.2 %        
1.800 kg     Pale Malt, Maris Otter (5.9 EBC)         Grain    2   16.2 %        
0.780 kg     Munich I (Weyermann) (14.0 EBC)          Grain    3   7.0 %         
0.680 kg     Caramel/Crystal Malt - 30L (59.1 EBC)    Grain    4   6.1 %         
0.220 kg     Crystal Malt - 60L (Thomas Fawcett) (118 Grain    5   2.0 %         
0.060 kg     Chocolate Malt (689.5 EBC)               Grain    6   0.5 %         
5.00 g       Hop Extract [50.00 %] - Boil 90.0 min    Hop      7   23.2 IBUs     
36.00 g      Goldings, East Kent [5.00 %] - Boil 30.0 Hop      8   12.0 IBUs     
26.00 g      Styrian Goldings [5.00 %] - Boil 30.0 mi Hop      9   8.7 IBUs      
44.00 g      Goldings, East Kent [5.00 %] - Aroma Ste Hop      10  0.0 IBUs      
44.00 g      Styrian Goldings [5.40 %] - Aroma Steep  Hop      11  0.0 IBUs      

1.0 pkg      English Ale (White Labs #WLP002) [35.49  Yeast    12  -             

50.00 g      Oak Cubes (Secondary 7.0 days)           Flavor   13  -             
30.00 g      Styrian Goldings [5.40 %] - Dry Hop 0.0  Hop      14  0.0 IBUs      
									

Yesterday we brewed the Summer Pale Ale mentioned a couple of posts ago. The recipe basically stayed the same, but we upped the 90 minute and 30 minute Chinook additions to 20 g each, in order to get some more bitterness. We managed to boil off a little more wort than expected, so ended up with around 25 liters of 1.055 wort instead of 30 liters of 1.050 wort. Oh well, guess this will be more of a IPA than an APA. We managed to screw up slightly with the flameout hop addition, as normally I always use mesh bags for whole hop cones, but this time I tried adding them freely into the wort. This of course meant that some hop debris made it into the pump, which jammed while we were transferring the wort to the fermenter. Luckily it jammed with just a couple of liters left in the kettle, meaning we didn’t lose much wort. Lesson learned, always use hop bags during the boil. We pitched with a healthy dose of WLP002, and adjusted the ambient temperature to 16 C. Hopefully it won’t be too low for the yeast. We mashed at 62.8 C (145 F) for an hour, follow by 15 minutes at 68.3 C (155 F) and 15 minutes at 76 C (169 F), to produce a highly fermentable wort. Hopefully this will become a tasty brew to drink during the hot summer days! We bottled the Amarillo Hefeweizen as well, and it tasted quite promising. The aroma was dominated by banana and lemon, and the flavor was surprisingly light. Will see how this one turns out in a couple of weeks!

• Brewery: Sly Cat Homebrewery
• Country: Finland
• Style: American Pale Ale
• ABV: 5.0 %
• Size: 330 ml
• Bought from: -
• Not on Beer Advocate
• Not on RateBeer

Yet another post for today (I should learn to spread the posts out over several days), and now it is time to taste the rebrew of From Seamless To Shameless I brewed for Team Seamless of Aalto’s PDP Course in the beginning of March. The beer has been well received, and compared to the first version, the second version is maybe slightly more bitter. I have one bottle left, so I thought I’d write up a review on it. The malt bill is simple, and consisted of Pale Ale, Vienna and Crystal malt. The beer was hopped with Simcoe and Cascade and IBUs should be around 30. The beer was fermented quite cool with US-05, so it should hopefully be quite clean. I kegged the beer together with a small amount of Simcoe and Cascade about a month ago, and transferred it to bottles about two weeks ago, so the beer should have had a little time to mature, but is still hopefully features some nice hop tones. Let’s see how it tastes!

From Seamless To Shameless 2
Appearance
The beer pours with a just slightly hazy amber-orange color. A compact white-colored head is formed and the structure of it seems fairly solid. The head collapses quite slowly and it leaves drapes of lacing along the glass. Not a bad appearance.
Smell
The aroma is quite hoppy, with citrusy and floral tones dominating. There is a slight underlying tropical fruitiness, that brings my thoughts to mango, which could be from the Simcoe dry-hop. The aroma is not all hops though, as there is a slight caramel- and honey-like maltiness hiding in the background. The aroma is not that potent, but that is not a bad thing in a easy-to-drink 'beer for the public' like this. No off-aromas or otherwise off-putting smells either. Quite promising!
Taste
As the beer enters the mouth you are first hit with a caramelly, honey- and biscuit-like maltiness that is reminiscent to what was found in the aroma, but the taste is much more potent. The malt tones work very well, and these are joined by a citrusy and floral hoppiness. You can tell that quite a lot of late hops have been used, as the hop flavor is really present. The finish is slightly bitter, much less so than I had expected, and quite dry. The lower bitterness is not a problem either, as the beer still feels well balanced, and this makes it more drinkable for the larger mass as well. If I would rebrew this solely for my own enjoyment, I would probably up the IBUs by around 10-20 (making it border on IPA territory) as I think it would complement the strong malt and hop flavors better. Still, this is a very tasty brew. When I tasted the beer is connection with bottling it had a slightly sharp/astringent bite, but that is all gone now, and I assume it resulted from over-carbonation in the keg (carbonic acid bite). Quite happy with this one. Not perfect, but really good.
Mouthfeel
The beer has a medium body and carbonation level. It is very easy to drink, and the citrusy hop flavors make it really refreshing.

Overall

As I already mentioned, I'm quite happy with how this one turned out. Since it's quite fresh still, there is a lot of nice hop aroma and flavor left. The bitterness was maybe slightly on the low side, and I think this same recipe would work very well for an APA/IPA hybrid with an IBU around 50. The malty and biscuity flavors were surprisingly strong in this one, despite the quite simple malt bill. I really like using a large fraction of Munich or Vienna malt in my recipes, as I think it brings quite nice tones to the flavor. Hope I can achieve something similar with the beer we're brewing on Monday!

I’m really happy to announce that my manuscript entitled ‘Influence of valine and other amino acids on total diacetyl and 2,3-pentanedione levels during fermentation of brewer’s wort’ has been accepted for publication in the Applied Microbiology and Biotechnology journal. As soon as it is published or available online I’ll post a link to it here. It is an interesting read if you are interested in how amino acids in wort affect diacetyl production. Here is the abstract:

Undesirable butter-tasting vicinal diketones are produced as by-products of valine and isoleucine biosynthesis during wort fermentation. One promising method of decreasing diacetyl production is through control of wort valine content since valine is involved in feedback inhibition of enzymes controlling the formation of diacetyl precursors. Here, the influence of valine supplementation, wort amino acid profile and free amino nitrogen content on diacetyl formation during wort fermentation with the lager yeast Saccharomyces pastorianus was investigated. Valine supplementation (100 to 300 mg*L-1) resulted in decreased maximum diacetyl concentrations (up to 37% lower) and diacetyl concentrations at the end of fermentation (up to 33% lower) in all trials. Composition of the amino acid spectrum of the wort also had an impact on diacetyl and 2,3-pentanedione production during fermentation. No direct correlation between the wort amino acid concentrations and diacetyl production was found, but rather a negative correlation between the uptake rate of valine (and also other branched-chain amino acids) and diacetyl production. Fermentation performance and yeast growth were unaffected by supplementations. Amino acid addition had a minor effect on higher alcohol and ester composition, suggesting that high levels of supplementation could affect the flavour profile of the beer. Modifying amino acid profile of wort, especially with respect to valine and the other branched-chain amino acids, may be an effective way of decreasing the amount of diacetyl formed during fermentation.

• Krogerus, K., Gibson, B.R., (2013) Influence of valine and other amino acids on total diacetyl and 2,3-pentanedione levels during fermentation of brewer’s wort. Applied Microbiology and Biotechnology. In Press. DOI: 10.1007/s00253-013-4955-1

Next Monday we will be bottling the first batch of beer we brewed at the new garage brewery (Amarillo Hefeweizen), and while we are there we thought we’d brew up a new batch of beer. Light, refreshing, and hop-forward beers are my favorite to drink during the summer, so the next beer will be a slightly larger batch of American Pale Ale (will still have to think of a better name). The malt bill will be simple, consisting of Pale Ale, Munich and Carapils malt (no Crystal, since I want a dry finish). The beer will be bittered with Chinook, and flame-out hopped with Cascade and Centennial. The same hop combo will be used for dry hopping. The beer will be fermented with my new favorite yeast strain, WLP002 English Ale, which I think works well in most styles of beer. You can get it to attenuate by mashing low.

Recipe: Summer Pale Ale
Style: American Pale Ale
TYPE: All Grain

Recipe Specifications
--------------------------
Boil Size: 40 l
Post Boil Volume: 35 l
Batch Size (fermenter): 30 l   
Bottling Volume: 28 l
Estimated OG: 1.047 SG
Estimated Color: 11.4 EBC
Estimated IBU: 29.1 IBUs
Brewhouse Efficiency: 60.00 %
Boil Time: 90 Minutes

Ingredients:
------------
Amt          Name                                     Type     #   %/IBU         
3.500 kg     Pale Ale (2-row) (6.0 EBC)               Grain    1   45.8 %        
2.800 kg     Pale Malt, Maris Otter (Thomas Fawcett)  Grain    2   36.6 %        
0.950 kg     Munich (20.0 EBC)                        Grain    3   12.4 %        
0.400 kg     Cara-Pils/Dextrine (3.9 EBC)             Grain    4   5.2 %         
15.00 g      Chinook [13.00 %] - Boil 90.0 min        Hop      5   16.9 IBUs     
15.00 g      Chinook [13.00 %] - Boil 30.0 min        Hop      6   12.2 IBUs     
45.00 g      Cascade [5.50 %] - Aroma Steep 30.0 min  Hop      7   0.0 IBUs      
45.00 g      Centennial [10.00 %] - Aroma Steep 30.0  Hop      8   0.0 IBUs      
1.0 pkg      English Ale (White Labs #WLP002) [35.49  Yeast    9   -             
45.00 g      Cascade [5.50 %] - Dry Hop 5.0 Days      Hop      10  0.0 IBUs      
45.00 g      Centennial [10.00 %] - Dry Hop 5.0 Days  Hop      11  0.0 IBUs
									

Now that the garage brewery is finally up and running I thought I’d brew up a couple of batches for the summer. The Amarillo Hefeweizen is fermenting along slowly but nicely (its fermenting at the cold end of the recommended range, 17C, in order to minimize the production of isoamyl acetate) and I will add the dry hops next Thursday, after which the batch will be bottled Monday 29.04. During the bottling I will also brew a big batch of American Pale Ale (Pale Ale 83%, Munich 12%, Carapils 5%; Chinook, Cascade and Centennial; WLP002) for the summer. The following week, it will be time for an Oak-Aged English Strong Ale / Barleywine (recipe still under development, but will aim for an OG of around 1.100 and a malty flavor profile) and the week after that an Imperial IPA (Pale Ale 84%, Munich 12%, Carapils 2.5%, Crystal 100 1.5%; Hop Extract, Cascade, Centennial, Chinook, Amarillo and Simcoe; WLP002). During May I’ll probably brew up a batch of (Imperial) Stout/Porter for next winter as well, but will have to think about a recipe for that one still. Gonna be a good brew summer!

Today we brewed our first batch of beer in our new brewing garage. The batch was the Amarillo Hefeweizen mentioned in the previous post. Overall, the brewday went quite smoothly, but we had a few hiccups during the mash. The post-boil wort was tasting promising though, so hopefully this will result in a nice and refreshing beer for the summer! We managed to squeeze out 24 liters of 1.049 wort, so efficiency was around 67% (better than usual). Below are some pictures of the garage and the brewday.