I had something happen that some of you may find interesting...

Yeast Starter:
After fermentation I normally save "sloppy slurry" of the yeast, and if it's within a few months will repitch it in a yeast starter, then into my wort to make new beer. Someone from my homebrew get-together group had suggested, if making a bigger brew, put the bag into a smaller brew kettle after pulling it out of my main brew kettle, add some water and make more "starter"... Normally have to boil it for a while to get it to 1.040. It's a good tip and I don't have to use DME.

Brew Competition:
Last spring I entered a homebrew competition where with a Dry Irish Stout, but got graded down harshly because the testers could taste some smoke in the beer and it’s not supposed to have it. One said it could have received a much higher score but would have had to be in a different category... Been racking my brain how that could have happened for the past few months, to no avail...until today, and I think I know how this happened.

Brewing big batches is what I’ve been doing, because as much as I like to brew, it’s hugely time consuming and eats up most of a day. I brew extra, and what I can’t put in keg I put in clean & sanitized milk jugs...then when the keg gets low I have some to top off. So if 5 gallons fits in my Corny Keg, I normally brew 8+ gallons and remainder is filled to the top in milk jugs, plus perhaps a few beer bottles...

Anyhow, brewing a large Rauchbier (smoke beer) today, with a bigger grain bill to maximize my large boil kettle, thought about using the spent grain to make enough wort for several starters... Then realized that would cause everything brewed from the starter to have a slight smokey flavor.

Apparently yeast absorbs some of the smoky flavor too. So for example Schlenkerla’s Helles has no smoke malt, but uses the regular repitched yeast from the rauchbier Maerzen, and it has a slight smoky flavor. Beer & Brewing Magazine had an interesting article on that, written by Conrad Seidl.

Anyhow, thought some of you may find this interesting... I certainly did. Cheers!

Hope your trip was amazing and great to have you back

Great to see you identified the problem . Unfortunately, that method is only really going to work if you were either using a very plain grain bill or intended to make the same recipe.

The other problems include how you store the resulting wort safely (freeze it) and the sheer volume of the starter wort which is going to take up a lot of space in your freezer.

Slurry is pretty potent stuff though so why not just stick with that I reckon? It's easy, safe and requires less space? You'll already know this Scott but I'll write a new thread on Yeast Slurry Harvesting next for other readers and it can also act as a draft for an article on the new site.

Definitely a great policy if kegging to brew more than you need and bottle the rest as it's very easy to do. So many advantages to it: you can force carb some bottles straight away; you can naturally carbonate some bottles and compare that with your draft beer; you can store some bottles for months after the keg is finished and see if these extra months change anything; you have some bottles that are ready to take-away to a party etc.


Pat

Hey Pat,

Why are you saying that technique of saving wort like this will work only with very similar grain bill...? Obviously it is best NOT to use super unique malt profiles for this, like the Rauch malt. Probably same with real dark malts or malts with really strong flavor profiles. But I don't see the problem besides that. No matter which malt is saved, I separate into 16 ounce starters and dilute / condense @ 1.040 gravity and store into 1-gallon zip-lock bags and freeze the wort (upper freezer portion of my beer refrigerator that stores 6 ea 5-gallon Corney Kegs in the bottom part). Not following what the problem is when brewing batches that are minimum 5 gallons VIF and up to 9 gallons VIF. Very small volume starter going into much larger volume wort.

Thinking about it - I have saved the trub at the end of the boil at least once or twice for the same use... It seems to have worked okay. I have ability to cold crash and drop the trub out - to the bottom of fermenter before putting in packaging. Using trub starter may not be the best practice if you don't cold crash your beer before packaging.

With using "Sloppy Slurry", I reckon that yeast die off there too, or become sleepy... Batch recently brewed, I decided NOT to use it because the slurry was 10-month old. I have used 6-7 month old slurry. But I build a starter and get it going again. The 10-month old slurry may have been able to get rejuvenated... Don't know for sure. But anyhow, unless the slurry is only 2-3 months old I build a starter and make sure the yeast is going good before I pitch it into wort.

The bottling extra beer is a good idea, and sometimes I do that - at least with a portion. But more often than that I save uncarbonated beer in gallon containers and then refill my keg. I've had some issues with the bottling and amounts of sugar to add. I've done some where add a small amount of regular sugar (like 1/8 a teaspoon). It works...but sometimes a little too much. Someone told me it is best to get a sugar solution (add some water to sugar and heat it up). Sometimes bottling the beer makes it not as good as kegging. That's my take.

You had mentioned posting something on bottling, using plastic pop bottles, different ways of adding sugar (a year or two ago). So any cool posts like that with good info are always interesting and could be good additional info. I've had my eye out for the bottling post you were going to write for some time now.

So anyhow, I'm certainly willing to admit fault if I screw up somewhere. For example the stout that had a faint smoke flavor in it... (Not major). Two judges working side-by-side, one could have mentioned it to the other and the other agreed... Almost for sure had to have come from reused rauch malt... Had to be "user error". I take credit. But on the other things, I don't see a problem with my process. If there are errors here and I am ignorant of some things that maybe should be obvious...please enlighten me.

Hey there Scott

I read your post this morning before heading out to earn some dollars, (it's Sunday here too!) and loved it. Here's why...

In my last post in this thread (written at 9:30am), I wrote, "I'll write a new thread on Yeast Slurry Harvesting," thinking that it would take me two or three hours to "knock up" the article. I got to bed at 5:30am the next day and the article is still unfinished.

While not all of those 20 hours were spent writing, I'm embarrassed to say that most of them were .

What I quickly ran into is the problem, yet again, of definitions. This site, as you know, spent several years just working on developing Clear Brewing Terminology. I thought we had that sorted until I began writing this article.

For a start, there's no clear definition of harvesting. I won't even mention slurry, rinsing and washing.

But, let's forget that and just look at the word, "starter." For example, you'll often see the phrase, "make a 2 litre starter." What is not clarified is what to do with that 2 litre starter. My great mate Case who lives just up the road, for most of his beers, uses liquid yeasts and "starts" them with dry malt extract. He the pours all of the starter into his batch.

Now, if you did that but instead of using dry malt extract, used some Rauchbier wort, for an APA, you're definitely going to have a problem.

But, other brewers will make a 2 litre starter and then tip the upper layer (say 1.5 litres) down the drain as the upper layer has negligible yeast. So, would this method using Rauchbier wort for a starter pitched on to an APA still be a problem?

So, coming back to your question, I'm not sure which of the above methods you are using and, in many cases, it wouldn't matter which method but...

I'm still too scared to open the unfinished article and I suspect that maintaining that fear is healthy for now. (There's a lot of other articles that need writing and that I can write.) However, I did write an analogy, something like, "just like when you cook a single rasher of bacon in your home, the aroma will linger for hours after, some malts, will..."

I think you get the idea

So, to sum up, I'm still working on clarifying several definitions for that article. One thing I will do is send what I've written so far to you because, to paraphrase Lily Allen, "I don't know what's right and what's real," [harvesting etc, terminology-wise] and, "I'm being taken over by the fear," of never getting any of the basic stuff written .


Pat

P.S. Re using different priming sugars. Yep, Sarah and I did do an experiment on that and I tried to find the notes on it a few months ago but they have disappeared! I can't remember if I wrote them up on the site somewhere. Put a bit of work into that so it's annoying not being able to dig up the results. I think, but can't be sure, that white sugar stood out but not in a good way. I also suspect that there is no one correct priming sugar e.g. maybe brown sugar is good in a stout??? One thing I do know is that I have had, on several occasions, the same batch split in half with one half naturally primed and the other forced and they resulted in two distinctly different beers. (That's why it's not a bad idea to brew a bit more than you can keg. More beer and more data!)

Hey Pat,

Sounds like you’re burning the candle at both ends...

Harvesting Yeast - is “washing” necessary?
For what I do with yeast, absolutely not... I’ve read a ton on brewing, and likely remember a sad 5-10%. If I had to go through the process of actually washing Yeast, I would never do it. Too much labor involved for too little gain. Just saving the slurry in a cleaned and sanitized jar works well. Store in beer refrigerator. If it took much more work to do - I would purchase fresh Yeast each time. Guaranteed.

When making a Yeast starter and waking the Yeast back up before using it, sometimes something seems off, an odd smell or something seems off so I discard Yeast and start over with fresh yeast.

We’ve all read articles about “how many generations of Yeast be kept” before it genetically mutates or otherwise changes and must be discarded... For me I don’t think I’ve kept it past 3-4 generations before something seemed off and it was discarded. If brewing in quicker succession it seems to work better than rejuvenating when it has been 6-7 months since past brew.

A lot of breweries (most?) reuse yeast like this. And there frequently are times they are starting to have problems with a yeast and have to buy more. And this thing about yeasts lasting only so many generations or mutating... How do major breweries keep their yeast in good condition? Or how do yeast labs produce good yeast? Likely [mention]ShorePoints[/mention] would be more helpful writing about this, since I think he retired from doing scientific work, etc. Would be interesting to read short article about. But I will only take the easy route...

Reusing yeast from Rauch Beer, or yeast used in Rauch Malt starter:
I read article recently. Author says that it isn’t just the Malt, rather the yeast itself absorbs smoke from fermenting in Rauch Malt and gives resulting smoke flavor. From yeast... (Beer and Brewing magazine, article by Conrad Seidl, came up in internet search and do not see date). Ran into this info a couple weeks back...

Reusing Yeast from Large Gravity Brews:
I hear what you say, but have done this before...with success! Same person that gave me the other tips on saving Malt for starters (etc), he’s kind of the “grand-daddy” of of our homebrew get together group. Because of reasons you state he advised building a large starter a couple weeks prior to brewing... Then idea was to build another starter prior to actually using. But my first starter took a little while, but then worked really well and I didn’t do the second starter build.

Sometimes when pitching, if starter / yeast ran its course I Cold Crash and drain beer off before pitching. But probably 2/3 the time it isn’t that far along and I end up pitching the whole thing into my wort.

Think this is enough for now. Interesting discussion. Appreciate response especially with as busy as you are. And I did read your other info. But not sure I am tracking with the yeast washing, etc. And I think some things are not a problem if you use proper caution. Hadn’t heard about hops causing issues with yeast... Do you have backup data on that? Most of my starter wort is pre-hops. But hops are a preservative and will help against spoiling. Brew “grand-daddy” had some tests conducted with that too.

Scott
My science experience was in a chemistry lab, not biology. Yeast is alive, so it is different.

However, before I started home brewing I took up baking bread. Sourdough became my interest and that’s yeast. I learned how to start a starter from a humorous book “52 Loaves” by William Alexander and saw no net difference if a procedure from a different authority was used. There is lore (myth?) that local airborne yeast will invade and eventually dominate in a growth medium exposed to the air. The idea leads to an explanation of why San Francisco sourdough is special. I’ll leave it up to a biologist to do the DNA sequencing to prove or disprove that.
My sourdough starter began with slices of apple and plum with their natural dusting of yeast on their outside skins. After two weeks under cheesecloth @ room temp with stirring and swapping out flour, it took on a life of its own. It made good bread. After two years of use with feedings not less than 10 days apart (it is like having a pet), it mutated - the odor was suddenly different - and I haven’t a clue as to why. It still made good bread. Eventually, it underwent another mutation and the odor was “off” so I tossed it and started again. For shame; some families have sourdough starter handed down from generation to generation. Mine lasted ~5 years.I hope nobody gives me a 300 year old Bonsai tree, I couldn’t handle the pressure.
I now have three different sourdough starters - bread flour (strong flour to some), whole wheat flour and dark rye flour. I use a mixture of all three and no additional yeast is needed. The key is to feed the starters at the right time in advance of employing them in the batch.
Back to beer and harvesting yeast - I am no expert, but I have successfully harvested and re-used yeast from the bottom of a secondary fermenter. I have washed some batches and not washed some batches (WY1272, WY3711, WY1056 - my experience with these three may not apply to other yeasts). After storage in a mostly full wide-mouth jar (~1.5 cm sludge in 300 ml) of wort (or RO water) refrigerated for up to three months, I decanted the liquid and used the upper half layer of tan (suctioned off with a turkey baster) in a starter. That is, ~1 L of water with 100 gms of either dark LME or light DME boiled 5 min, cooled to 18 ºC, pitched, stirred 24 hr @ RT with punctured cling wrap cover. The liquid was decanted and all of the sludge was pitched into 20L of wort. One batch (highest OG = 1.065) took 30 hours until activity in the airlock was seen, others all got going inside of 24 hrs. Lately I have added 10 gms of flaked oats to the starter boil and strained them off on transfer from the saucepan to the starter vessel. It is supposed to provide nutrients to the yeast.
Whew, that’s a lot when I could just purchase a new packet of yeast. Notice I didn’t do it with US05.
How many generations? I am about to use number three/part II of WY1272 as it looks, smells and tastes good. This is going into wort with OG - 1.070, so I made a starter, harvested that yeast and made a starter with it. So it is really generation 4. Why do that? Local heat wave caused a delay in brew day AND I think it is like feeding my sourdough starter at the best time to introduce yeast that has the viability and vitality to do the job. Read up on yeast, you will see those two ‘v’ words. As for cell count, I do not know, but it will not be under-pitched.
Think of it as a living thing - it is!
Starters typically have SpG = 1.036 to 1.040. Yeast (liquid, re-hydrated or dry from a packet) can tolerate that environment. With an increasingly higher OG (>1.070), less-than-optimum yeast will not fare as well. Osmotic pressure, for one. Water inside the cell wall will migrate out to dilute the more concentrated liquid. Old, immature, or weak cells might not even survive. If the bell curve of yeast quality specimens is tall in the right range, we win.
If you are selling something (yeast) and your customers can buy once and propagate forever on their own, you sell less. If you sell something that can only be propagated 3 times, you sell more. If you can convince customers that it can only be propagated once, you will sell even more. I think the jury is still out considering how many times a specific strain can be harvested… Obtuse thought- why cure a disease when you can merely treat its symptoms and make more money?
If you have different experiences with harvesting yeast. let me (and the rest on the forum) know.

Interesting thoughts, [mention]ShorePoints[/mention]... Especially interesting was your sourdough bread yeast story.

John Palmer says to use 1.040 starters, so that’s what I do. And am convinced if I pulled my yeast samples out and ran them through a starter so they are used every 3 months, it would probably keep them going much longer. Maybe forever. But would the yeast mutate...? Maybe. I don’t know.

Talked to homebrew group granddaddy Dennis again last night. He re-told a story of leaving 2 each 2-quart wort samples out uncovered. To one he added a few hop pellets. It developed a Krausen and turned into beer (wild yeast that worked fairly well). The other with no hop pellets developed “mushrooms” and had got nasty things that attacked it, so he threw it out. I don’t know the science behind this, but it is interesting. (He used this “home grown” yeast for several batches of beer until it was proving too aggressive and eating too much sugar / beer finishing too low, so he threw it out.

Aecht Schlenkerla Helles - same brewery that makes an amazing Smoke Maerzen... Last night I drank bottle of their Helles. No rauch (smoke) Malt, but a strong smoke taste. They repitch yeast from smoke Maerzen beer into their Helles and apparently ALL of the smoke flavor comes from the yeast.

Only 4.3% ABV... Once my Rauchbier is finished I will try to brew a similar Helles.

2nd beer on list:
https://www.schlenkerla.de/rauchbier/so ... rtene.html#

Thanks for the reads above. (Lol on the bonsai )

There's a difference between pitching onto a yeast cake, harvesting a yeast cake, washing and rinsing. Harvesting a yeast cake and rinsing it is very easy. I mentioned above, the problem in writing how to do it is in the definitions. I'm very stuck for time but will send my draft article to [mention]ShorePoints[/mention].

Regarding sourdough, search for posts on this site that were written by me and include the word 'sourdough.' In one of them (and there won't be too many) I talked on how, when you are going away and unable to feed your sourdough starter, you can dry it. In one of those posts I suggested it would be fascinating to try the dehumidifying method (basically you turn your sourdough starter into a dried biscuit) on our brewing yeasts.

Could be an experiment someone here could try or start a new thread, proposing the theory and asking for volunteers???

Thanks Pat. I just sent you an email. And reread your post (which you posted live on the site). Obviously you put some time on that. Thank you!

I spent several hours today researching and in many cases re-reading articles read years ago. Marshall from the Brulosophy blog has an interesting angle to yeast harvesting, based upon research as well, that is simple and I’m going to try in the future (next time I buy new yeast). http://brulosophy.com/methods/yeast-harvesting/ It doesn’t use harvesting off yeast cake, rather making an extra big starter at the start before fermenting your beer and saving a portion of that for future brews. And with new brews again make a large starter and split it for the future. This appears to take care of some of the issues related to different yeast harvesting techniques.

Thank you, Scott.
That seems to be the best answer involving flavor leftovers for this thread.
Storage of that remaining starter under wort/beer or washed is another choice discussed at that link. When preparing for the next brew, make another large starter and subdivide again. Repeat as desired. 12 generations is quite a lot, but as long as it works....
I think your homebrew group's advisor/sage may have also demonstrated how hops can suppress growth of undesired bugs, but then his starter has that carry-over flavor and we are back to the original question of this thread. So many choices involved.