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General Category => General Homebrew Discussion => Topic started by: sierranevadapromotion on May 31, 2011, 03:54:02 AM

Title: Ask Sierra Nevada’s Experts - Week 2 winners and questions
Post by: sierranevadapromotion on May 31, 2011, 03:54:02 AM
After a second week of diligent review to the questions submitted, the week two winners are…

Dan (900005294)

My question is about contamination:
After bottling a batch there was one bottle that foamed or gushed and when opened.  After pouring the beer was flat.  All the other bottles seemed fine so I suppose one bottle became contaminated.  I was very careful sanitizing.  Other than being flat the beer seemed to taste fine.  I did not detect any strange flavors or odors.  What kind of contaminant would cause this one bottle to gush, why did it go flat but still taste fine?

Dan, this one is tough…it could be a lot of things. Oxalate (Beer Stone or calcium deposits, which form nucleation points in the bottle—and kidney stones—and comes from malt.) This could affect one bottle if it were filled from the bottom of your carboy. It could be D.O.N. which is a malt-based fungus (but that would be in every bottle and also not very likely.)  It could be imperfect glass (a nucleation in the bottle itself)…we honestly don’t exactly know what it is, but I would bet that the beer wasn’t flat…it probably gushed and released the majority of CO2 in solution and the beer just seemed flat.

Greg Seitz & your wife is welcome, too!


I know that Sierra Nevada is on the cutting edge of new hop development and introducing these varieties to the public.  My question comes from this and an attempt to further involve my wife into home brewing (she is an avid gardener who experiments with cross breeding different flower varieties at home).  What are distinct characteristics that you look for when examining/experimenting with new aroma-type cultivars?   I have found a resource for male hop plants so that she can hybridize these with the commonly available female varieties to maybe create our own 'new' hop plant.  I understand that this may take several years but would be something she would be very interested in experimenting with.

Greg Seitz
registered user of the AHA Forum: Brewmonkeys

Greg, we don’t experiment with hop breeding here, but we work with hop brokers in Washington and Oregon to test the new varieties that they are working with. Generally speaking hop breeders are interested in: Yield (how many cones) Disease Resistance, Alpha for the big brewers and Aroma for the craft brewers. We’re really interested in hop oil levels and specifically beta-myrcene levels. This sounds like a very fun project….keep those thumbs green.

Additional questions and answers from week 2!


as a passionate homebrewer, i'm constantly working on identifying areas for improvement in my beer.  my most recent obsession has become water.

from reading gordon strong's most recent text (brewing better beer), my understanding is that at sierra nevada, all brewing water is treated to accomplish a pH of 5.5.  my first question, then, is: can this practice be extrapolated to apply to water irregardless of source?  in other words, should i lower my brewing water to 5.5 (our water is fairly alkaline and is characterized by temporary hardness).

perhaps more importantly, i guess i'm wondering whether or not water is the best thing for me to be focusing on.  i've had a fair amount of success in competitions and the like (and haven't tasted any problems in my beer that i'd necessarily associate with water), not to mention that i don't have a rigorous enough science background to fully understand water chemistry.  would my intellectual energies best be spent on another topic?

thanks a bunch -- would love to see you at beer camp,

jared long
laramie, WY

Jared, we DO in fact drop our brewing water pH to 5.5. Our water here in Chico is also quite alkaline and we have issues with hardness as well. We drop the pH mostly to ease on buffering…chiefly to lessen the extraction of tannins and polyphenols from grain husks. It also helps to drop out Calcium Bicarbonate.
To the question of whether your time would be better spent on another topic….I wouldn’t let the water get you down…If you are having good results in contests, take the judges feedback on what to look for in regards to changes with your beer.


        I recently heard that you pitch around .5 million cells of yeast per ml of wort per degree plato. I was wondering do you do this for every beer, and what effect does this lower pitching rate have on your final product? For example, how does it effect attenuation, fermentation times, and the creation of flavor compounds during fermentation?


Bryan Fishback
bpfishback on the aha forums


For ales strains that are NOT high gravity/high alcohol (over 7.5% ABV) the 500,000 cells/ mL/degree plato is accurate. Higher gravity beer we will increase pitch rate to about 1 million cells.   Lager yeast is a different story. With lagers we pitch 1.5-2 million cells/mL/degree plato and will double the pitch rate on the rare occasion that we brew high-alc lagers.
Our yeast is STRONG, LIKE BULL!
One thing about our pitch rate…We check our yeast viability with a hemocytometer and methylene violet to guarantee we have healthy yeast, and the percentage of dead cells found is not included in the pitch rate. So our .5 million cells are very healthy and virile. You can pitch as many yeast cells as you want, but if they’re dead or dying it’s not going to make difference!

Homebrew Torpedo System?  Week 2 Question
Looking for advice on a homebrew "Torpedo" set up.  I have the parts, but more of a procedure question.
Fermenter is a Blichmann Conical, 14.5 gallons.  The hops go in a Blichmann Hop Rocket.  March pump to recirc. the beer.
http://www.blichmannengineering.com/HopRocket/HopRocket.html  I see John has an upgrade for more flow, which might help.  Glad I looked up the link!
Should I try the pump before or after Hop Rocket?  Will an impeller type pump like the March 809 knock too much CO2 out of suspension, causing a vapor lock?
Jeff Rankert

Jeff, we don’t really have any experience with the Blichmann products and can’t speak directly about them…but if we were to guess, we say use the pump prior to the Hop Rocket. We’ve used impeller, diaphragm and positive displacement pumps. Impeller worked fine but positive displacement works better. You’re not interested in speed through the vessel, the more important factor is contact time with the hops and the varieties being used. As always, Oxygen is the devil. Purge all of your equipment and the hop bed thoroughly with CO2 before use. Good Luck!

How can I get my wife to like beer?


Eric J Allain, PhD
Assistant Professor
Department of Chemistry
Appalachian State University
My question is about pitching rates.

Eric, it’s a question for the ages! Experiment with different styles…(Beer styles we mean! Although other styles can be fun too)… We always say that people who claim to not like beer, are drinking the wrong beers. Pick a variety of types but don’t pander to what are typically thought of as “girlie styles” different strokes for different folks, you know! (My wife loves Double IPA’s but hates “fruity” beers)
Try pairing beer with food. Beer and chocolate is a great match… and also, try not to drink so much yourself…and do the dishes once in a while...and try buying flowers…and apologize now and then…tell her she looks pretty…those jeans do not, in fact, make her look fat.

I have heard a lot about making sure I pitch an appropriate amount of yeast for my beer, notably that underpitching leads to weak fermentations and sometimes fairly bad flavors. I have also read articles that indicate that *overpitching* can also lead to off flavors in the beer. This is why I try to always pitch the just-right amount, mainly by using Jamil Zainasheff's pitching calculator. My question derives from the uncertainty inherent in guesstimating yeast mass in harvested yeast:

How sensitive is homebrew-scale brewing to off-flavors resulting from overpitching? There was a recent article in Zymurgy about underpitching that seems to support the idea that underpitching should be avoided. But if I'm not certain about how much of the goop in my sterile mason jar is actually viable yeast, should I err on the side of overpitching, and if so, how much err can I do? I typically harvest somewhere around 1L of solids from each 5gal bucket (heh, mixed units), and the yeast-pitch calculator tells me to put in about 250 mL of solids based on my best-guesses on cell concentration and non-yeast percentage. The last time I did this (and the first time I was working with the English Ale yeast WLP-002), I feel like I probably
underpitched- the fermentation was slow to start at least. The flavors seem okay, but I don't have a comparison batch and the brew is still just a week in the bottle (I really only did a sensory on the gravity sample). Time will tell.

Anyway, if I'm worried about underpitching, at what point do I start worrying about overpitching by compensating? Am I better off using 150%, 200%, or more of the recommended yeast volume? At what yeast pitching rate do we start seeing real detriments to flavor?

Even if you don't pick me for beer camp (which would be awesome, don't get me wrong), I am really interested in figuring this out. There's so much uncertainty in guessing pitching rates without a hemocytometer, I want to know where to put the mean of my gaussian distribution to maximize the probability I'll get good beer.

Eric Eslinger
AHA member: 213047

Eric, you’ve clearly put a lot of thought into this question. When in doubt, it is always better to over pitch. Unless you’re grossly over pitching you’re probably not going to have a problem with off flavor. Yeast tends to work on a factor of 10…so if I were to intentionally over-pitch I would aim for 100% over the recommended rate. If that doesn’t work going 150%
As an aside, we recommend that you don’t harvest yeast there’s no way to guarantee viability. Buy fresh cultures ya’ cheapskate.

Sierra Nevada Experts,
There are so many equipment options out there for the home brewer to purchase for their brewery; I thought I would ask:  What would be your top five equipment purchases in order of priority for the average “budget conscious” all grain home brewer and why are each important?   When I say “budget conscious” I just mean I want to buy the right equipment the first time and start with the equipment that has the greatest impact on the quality of the beer.  Thanks a lot, look forward to hearing from you.

Eric Schwarzkopf

Eric, it’s hard to recommend specific equipment..we’re a little detached from the homebrew-scale market. That said, the things we find the most important are: good mash/lauter tun, wort chiller, and the number-one thing…Temperature controlled fermentation!!! (Get a second fridge and some carboys and don’t ferment in plastic.)  Most important…drink lots of Sierra Nevada Pale Ale to calibrate your palate.

Respected Brewers,
How does a brewing company like Sierra Nevada adjust their water chemistry (if at all), for brewing so many different styles of beer & crafting such great products?
Thanks, for brewing such amazing beers.
Kit Butterfield

Kit, we do change mashing and kettle salts for different beer styles. For example, we add additional CaCl2 Calcium Chloride in our Porter and Stout for enhanced mouthfeel. We add more CaSO4 Calcium Sulfate dependant on pounds of malt per barrel.   


I have been trying to fix a diacetyl problem in my lagers and hybrid beers and have been unsuccessful. I have tried doing a diacetyl rest with 1/3 and 1/4 of fermentation left to go and using a two step starter from an activator pack to a 2 L to a gallon volume. A also tried not doing any rest and just fermented at 50 degrees for the entire fermentation. I have tried doing diacetyl rests in the primary fermenter and in the secondary (not on the same batch). I have taken samples at various points during fermentation and rests with a cleaned and sanitized wine thief. Most of the batches have not had any noticeable diacetyl immediately after the diacetyl rest. Not long after chilling and carbonating the beer at 40 degrees, a diacetyl flavor becomes apparent. I do not have an issue of diacetyl becoming apparent after chilling and carbonating, so I don't think it is a contamination issue. Could my diacetyl issue coming from my chilling process? Is the diacetyl being released again after being absorbed during the diacetyl rest?

I have consulted many books and forums and can't find any answers, that is why I need your help and Beer Camp to figure out what I need to do differently.


PS I am BrewBeard2009 in the forum, the email address attached to that account is warren.billups@live.bemidjistate.edu, just in case

Warren, good question! Diacetyl is a tricky thing. I can give you what we do: We pump-into the fermenter at 48 degrees. We let the yeast rise to 50 degrees, and maintain fermentation temperature until our gravity reduces by half. At that point we turn off temperature control and allow the yeast to finish fermenting which will aid in the breakdown of 2,3-BUTANEDIONE (diacetyl) We analyze for diacetyl but a quick home test: take a fermentation sample (200mL) put  it in a bottle and immerse it in a water bath at about 165 degrees for 45 minutes. Smell it…if you can smell butter, the beer is no good and you need to leave it on the yeast longer. Generally speaking, our lagers take 7 days to ferment, and an additional two days to reduce diacetyl. At that point, we crash chill.
It could also be a bacterial infection (pediococcus produces lots of diacetyl) but you would probably be able to taste that. Butter is bad… do what ya’ can to kick out the stink.

Aloha Sierra Nevada Experts,
It is often necessary for me to wear rubber boots while I work.  After a long day of work, my feet are dry and safe from harsh chemicals, but boy my dogs are tired and sore!
Can you recommend a brand of rubber boots that will provide my feet with protection and comfort?  I figure with at least 30 years of brewhouse experience you may have found boots that fit the bill.
Mahalo for your help, and your delicious beers too!
 With aloha,
Carl Saxer
Hilo, Hawaii

Carl, no, we can’t recommend a comfortable pair of rubber boots…they’re all built like medieval torture devices, designed to crush your will to live. Most of our brewers wear slip-resistant shoes but try not to wear boots if it can be avoided. If you’ve gotta’ wear rubbers, insoles help!  Don’t run your dogs all day, you’re in Hawaii, a little beach-time will help.