Standard Lager In Mexico

It's hard to ferment a lager at the proper temperatures here in San Miguel. Although I'm able to chill the wort down into the low to mid 50's f. with a plate chiller and post (ice bath) chiller, without a cold room or jacketed fermentor I'm helpless against the impact of the ambient temperature during the fermentation period.

I considered this problem and decided to go ahead anyway and brew a version of my previously successful Pabst Blue Ribbon clone. My original recipe that I brewed while back in California is made up of 75% 2-row, 3% Munich malt and 22% Minute Rice and I generally followed the same recipe and lager yeast with one fairly large exception. In this case I used short grain white rice that I pre-cooked and then mixed in with the mash rather than going the easy course by using Minute rice. I also substituted a small percentage of crystal #20 for the Munich malt I used in the original.

I decided that my best approach for brewing this beer down here was to brew in the middle of January when the daytime temperature was in the low 80's f. but the nighttime temperatures got down into the 40's and 50's and the fermentation chamber was a constant 60f. Secondly, by starting with a low pitching temperature to begin with I could at least minimize the active fermentation temperature rise. I allowed for a full two week fermentation and during the height of active fermentation the temperature rose to 65f. before settling back down to the ambient 60f.

Unfortunately, a negative result from this warm ferment was an abundance of acetaldehyde. The positive result was an attenuation of close to 80% allowing for a very dry beer which is what I wanted but I was still concerned that all was lost because of the taste.

Long story short, this beer was initially undrinkable because of the high level of green apple flavor from the acetaldehyde by-product of the high fermentation temperature. I set the four cases of beer aside hoping that time would heal this wound. These beers sat at room temperature (65f.) for the last three months. I cracked one open the other day to see what was happening with them and was happily surprised to find that the green apple was gone. I was shocked when I tasted a seemingly new beer that is crisp, dry, clean and very enjoyable.



It's nice to know that brewing a lager with non-standard procedures along with a little time and patience can result is a beer that makes you question the conventional wisdom and strict rules that suggest lager brewing isn't for everyone.

 



 

Russian Imperial Stout Comparison

I like North Coast's 'Old Rasputin' Russian imperial stout. It's a good representation of the style that isn't crazy alcoholic and allows for easy consumption. So, when I developed the recipe for my RIS I kept Old Rasputin in mind and focused on big roastiness with balanced drinkability.

I use 85% domestic 2-row and a mix of roasted and Munich malt for the remainder of the grist. I don't use any caramel malt in this brew but shoot for straight forward roasted flavor. The bittering is about a 1 to .75 ratio with a 60, 15 and 1 minute additions that imparts a small amount of citrus/pine from a charge of centennial hops.



Russian Imperial Stouts

Although this beer is extremely young (8 weeks) I couldn't wait to sit down with friend and The Beer Company owner Antonio to do a taste comparison with Old Rasputin. Our focus was to evaluate the differences between the two beers and come to a consensus on improvements needed for future batches.

In the pictures attached, my stout is in the plain glass and Rasputin is in the Delirium glass. As you can see the beers are remarkably similar in head color and retention as both dropped down to a dense and viscous layer that remained that way until the end of the sample.
The mouthfeel was slightly different in that my beer was full and round and the Rasputin felt more resinous and thin but with more carbonation.

My beer has a predominant chocolate presence along with the typical roastiness and some earthy qualities compared to Rasputins up front coffee, caramel and even though both beers come in at 9% abv the Rasputin's alcohol presence is evident, very different from mine in this way. It is also more bitter by I would guess 6-8 ibu's.

Overall I'm pleased with my RIS with it's robust chocolate and coffee qualities but there are a couple small changes I will make on the next batch beginning with higher ibu's and just a touch of crystal #60 for some caramel taste as a minor player.

Two Factors For Better Attenuation

I enjoy my beers on the dry side and regularly use well attenuating yeast to ferment with for the most part. My go-to's are Safale US05, and Whitelabs Wlp001 and Wlp500, but on occasion I will still end up with beer that is under-attenuated as the yeast leaves behind unfermented sugars when it drops out of solution and goes dormant.

I scratch my head confused and frustrated by these results after feeling like I made sure I did everything right. My fermentation temperatures were within the optimum range and consistent and the wort was well aerated. I'm convinced that all of my brewing practices were perfect for a complete conversion only to be disappointed when the yeast wasn't able to complete its task. But there were a couple lessons that I had not learned yet and they needed to be addressed.

Two main reasons that under attenuation occurs that I wasn't considering with the seriousness that it deserved was the accuracy of my mash temperature and the level of my mash ph.

The importance of strike temperature

 

 

I often took a careless approach to the important effects of mashing at either too high or too low a temperature which can either limit the effectiveness of one of the essential enzymes and or denature and stop other enzymes from effectively breaking down starches into simple sugar molecule chains, something the yeast is relying on us as brewers to execute well, for their ease of metabolism.

 

I am now very careful about getting my mash temperature to within a degree or two at the beginning of the mashing time. My strike water temperature for the grain to water ratio that I use is 166-168f. which leaves me with a consistent rest temperature of 149-151f. Knowing this, I can achieve a slightly more fermentable wort by lowering my strike temperature by a couple degrees or raising the temp. for a slightly less fermentable wort. But I still regularly confirm a proper mash temperature after thoroughly mixing in the grist. I do this by comparing my mash tun thermometer for accuracy on occasion to make sure I'm getting proper readings. This is achieved by taking the temperature of the mash with another thermometer, one that I know is accurate. I stab down into the mash from above, moving around to different areas of the grist, I then compare this reading with the built in thermometer, essentially getting a consensus from the two readings.

The importance of mash ph.

 

 

The other factor that effects yeast and one in which I paid little attention is mash ph. A mash ph. that is alkaline or above the optimum 5.2 to 5.7 range will again effectively leave you with long chains of sugar in the wort as the beta amylase enzymes work best is an acidic environment. An alkaline environment limits this enzyme activity thus leaving the yeast with a difficult time of metabolizing.
When brewing with hard water, relying on the grain bill to lower the mash ph. may not be enough and so other steps must be taken. A couple simple solutions would be to dilute the brewing liquor with distilled or reverse osmosis filtered water essentially softening the water, adding calcium in the form of gypsum and/or adding acid to the mash.

A dry beer ready to be drunk

 

The importance of these two influences in starch conversion should not be overlooked and if you are finding that your beers are coming in with low attenuation, should be considered as primary factors to investigate.

Now that I carefully manage these two areas during my brewing session I have been able to consistently achieve proper attenuation from my yeast and effectively manage the outcome of the remaining sugars depending on the style of beer I want. Cheers!