The TRUB yeast project


by Bob Hoaglan
Believe me, there should be a disclaimer here
but short of disregarding the whole thing
I wouldn't know what to disclaim!


The project

I had been testing out ways to send a single use yeast culture in the mail. In the past I had sent yeast on slants to brewers but there was always the problem of the end user not having the knowledge/experience or equipment to deal with yeast stored in that manner. Of course the knowledge/experience and equipment required is minimal but there was always that "fear factor" associated with doing something new that was hard to overcome.
The method of transporting yeast that I had been testing and thought would have the best chance for survival and ease of use on the other end was to send an inoculated Mini Starter. The end user would be able to treat that yeast culture in the same manner as liquid yeast purchased from the local brew store. Further, if the brewer's experience was dry yeast, only a simple instruction would be needed.


TRUB (True Rats United in Brewing) is a concept conceived by Pilz (AKA Dan Mistrot) whereby a group of brewers from the Brew Rat Chat, (an online AHA sanctioned homebrew club whose member base includes all of the US and has members in several foreign countries), would all brew the same recipe then exchange samples with the intent of having an online taste test/evaluation at a later, pre-determined date.

In early July the brew date of August 21, 1998 was set and a Sierra Nevada Pale Ale clone recipe was approved by all the brewers. Due to the diverse experience's/preference's of the BRC members, three variations of the recipe was formulated to accommodate all-grain, specialty-grain and extract brewers.

For the project I was working on, TRUB was the perfect vehicle to finalize my tests of transporting single use yeast cultures. And for TRUB, this was a way to eliminate one more variable in the brew process. After a discussion with Pilz and gaining his support, I sent out inquiries to the TRUB list and received 12 volunteers. All of the volunteers were in the continental US but pretty much dotted the entire country.

Timing and transportation environment were the important considerations, everything else was "text book". The Mini Starter would have to be inoculated, capped, mailed, set in a hot postal sack for 3 to 4 days and them possibly hibernate at the end user's house for another two to three days waiting to catch up to his brew schedule. In my tests at home these conditions were considered and somewhat duplicated.

The Test

The tests I conducted in-home were done in 24 ml screw capped borosilicate culture tubes. Several yeast strains were tested in various ways and all samples produced an active starter. There, however was the problem of CO2 gas pressure build-up. This could easily be handled with the Borosilicate tubes but I had planned on using the 10 ml Mini Starter's purchased from Brewers Resource and I was concerned about how the larger volume plastic tubes would hold up under the pressure. So I mailed out an inoculated Mini Starter to Pilz in Florida. The trip took 3 days and arrived with some leakage from the pressure build-up, but was acceptable. Then the inoculum was stored at 70F and burped occasionally for several days before being pitched to a starter. The starter kraeusened quickly and eventually produced a good beer.

I just wasn't satisfied with the pressure problem. So using the "two heads are thicker than one theory", I discussed that with Jeff Mellem, the proprietor of Brewers Resource . His Idea was to allow the inoculated Mini Starter to work for 24 hours or until completely worked out then gas off the bottle before mailing it to the end user. And in the final TRUB mail out that is what I did.

The Process used in the TRUB Yeast project

For the TRUB yeast mail-out; one 12 pack of 10 ml Mini Starters, one package of Super Wort and one Wyeast smack pack of 1056 American Ale Yeast was purchased.

Four days before the mail-out the yeast packet was removed from the refrigerator and "smacked" and allowed to work and swell to the correct height. The work area and all equipment to be used was sanitized including my hands with a spray bottle of alcohol. The yeast pack and the 12 Mini Starters were sprayed with alcohol as well and allowed to air dry.

The lids of all the Mini Starters were loosened all the way but not removed. I needed to be able to lift the lids with one hand while holding the smack pack in the other. The smack pack was shaken one final time to assure all yeast was in suspension and the corner was cut off with a pair of scissors. The lids of the Mini Starters were lifted one at a time, inoculated with 4 ml of inoculum from the smack pack and immediately replaced. The mathematics here is that there is 50 ml of inoculum in the smack pack and I had 12 Mini starters to inoculate. Because these bottles are graduated in 5 ml increments and each bottle pre-filled with 10 ml of wort, it was an easy task to determine when I had poured the correct amount of inoculum into the Mini Starter. When I had filled the bottles up near the 15 ml mark I would consider that good and go on to the next bottle. The last bottle would take the hit on a shortage or overage.

The Mini Starters were capped tight, shaken to suspend the inoculum and then the caps were loosened to allow pressure to escape. Then the Mini Starters were placed on a pie pan and placed on a warm dark shelf. Each Mini Starter was occasionally burped (the lid tightened, shook and the lid loosened).

The Mail-out

Five days before brew day, all activity had ceased in the inoculums (inoculated Mini Starters) and they were ready for transit. The lids were tightened and the inoculums were placed in an envelope along with a zip-lock bag containing 1/3 cup of Super Wort and a detailed instruction on how to process the inoculum and make the starter wort. These, TRUB Yeast Kit, were stamped with 78 cents postage and dropped in a mail box. All recipients received their kits two to three days before brew day with no unexpected surprises. 12 out of 12… pretty good for the USPS.

The Starters

For various reasons some brewers needed a larger than 500ml starter. And in that case I assume that the brewer followed the enclosed directions and used the supplied 1/3 cup of Super Wort, built a 500ml starter and then bumped that up with his own DME. That process would ensure that there would be a high enough cell count to deal with plain DME.

The Instructions
The following is a copy of the enclosed TRUB Yeast Project instructions.



This is a one size "fit's all instruction" for the TRUB yeast project so please don't be offended if it seems to remedial. There are as many ways to make starters as there is to put your pants on in the morning so feel free to do your own thing or to modify these instructions to fit your thinking and or your equipment, just remember the three rules of yeast starter making. "Sanitize, sanitize, sanitize".

Your package: You will receive a package containing your yeast culture in a small bottle and your wort ingredients in a zip-lock bag. That's it.

Inspection: Open the package and look at the small bottle. The lid should be tight and the liquid should be at or above the 10 ml. mark. Shake the bottle and then loosen the lid ¼ to ½ turn to release the pressure. Do NOT Remove the LID! Now with the lid still loose, sit the bottle in a safe place away from dogs, cats and curious humans and where it will remain at or about 75-80F temperature. If you receive this package before Thursday, Aug. 20, you might want to shake and burp the bottle of yeast another time or two to re-suspend the yeast in the wort. Do this by tightening the lid and shaking the bottle then loosening the lid ¼ to ½ turn and return the bottle to it's safe place. Equipment you will need: You will need a bottle to hold your starter, a piece of aluminum foil and something to boil your starter wort in.

The Bottle: Use just about any bottle that will hold 3 to 4 cups of liquid, preferably with a screw lid that you can sanitize. The neck of the bottle should not be too small because your going to be pouring liquid into it nor should it be too large because it will be difficult to manage when burping it. Experienced brewers will have an Erlenmeyer flask and if you know what that is then you can find a bottle with a neck that is similar in size or just a little larger and again preferably with a sanitizable screw lid. A BBQ sauce bottle should work fine. Test it to see of you have enough head room by putting 3 cups of water. You should have at least 3" of head space left in the bottle.

Aluminum Foil: You will need a 6"X6" piece of aluminum foil. This is to drape over the top of your starter bottle and down the neck and cramped with your hand. You will use this whether your bottle has a screw lid or not.

A note on aluminum foil. The bottom side of foil as it comes off the roll is sanitized well enough for this purpose, however, if you don't trust the sanitation of your foil then you can spray it with alcohol and allow it to air dry before use.

Boiling Vessel: You will need something to boil your starter wort in. Use something that you will be able boil in and also cool in. What works well is a 1 quart Pyrex pitcher. It has a pour spout and you can boil and cool in it and it has the added beauty of graduated marks on the side. This will makes your job easier. But what ever you select, remember that you will be pouring out of this into your starter bottle so it needs to pour well. If you have to use a sauce pan then you will need a funnel and this is just one more thing that will need to be sanitized.

Getting Started: On Aug. 20th you will want to make your starter. Allow your self enough time to do this. If you won't have enough time on the 20th to do the complete job you can make up the starter wort ahead of time and put it in the refrigerator till the time to pitch the yeast. If you choose to refrigerate then just make sure the wort is in the starter bottle, the cap (if used) is on and the aluminum foil is covering the top of the bottle. Also warn the refrigerated wort to room temperature before pitching the yeast to the starter.

The Clean: Clean and sanitize your starter bottle, cap and everything you will be using that will not be boiled (soak in a cool bleach solution for at least 20 min and then just before use rinse thoroughly in very hot water). You will probably use a set of tongs so clean and sanitize then too. Clean and spray bleach or alcohol on your counter top and sink.

The Boil: Dissolve the contents of the zip-lock bag you received in your kit in 3 cups of water and vigorously boil for 15 minutes.

The Cool: Cool in a water bath to 75-80F. Don't use a thermometer, feel of the pan and if you feel no temp than it's at the right temperature.

The Settle: Place a piece of aluminum foil over the top of the pan and let your cooled wort set for 3 to 5 minutes to settle out. There will be some heavy sediment that will precipitate out and settle on the bottom of your pan that you may want to leave behind.

It's OK to allow this sediment to be in your starter bottle but if it's there it's difficult to tell if you have yeast or sediment in the bottom of your starter bottle.

The Pour: When the wort is cooled and settled pour it straight into your freshly sanitized and rinsed starter bottle. Try not to allow the stream of wort to touch the mouth of the bottle.

The Pitch: Tighten the lid on the yeast bottle, shake well to suspend the yeast and immediately pour the contents into your starter bottle. Again, pour straight into the bottle without letting the stream touch the mouth of the bottle.

The Capping: If you have a bottle that uses a screw cap, then place your freshly sanitized cap tightly on your starter bottle and cover with a piece of freshly stripped aluminum foil (remove from the roll and immediately placed over the cap of the bottle). Shake well to aerate the wort and then loosen the lid ¼ to ½ turn to allow for pressure to escape. Leave the aluminum foil covering the top of the bottle.

If you are using a bottle without a screw cap then place a freshly stripped aluminum foil over the top of your starter bottle and crimp it around the neck. Tightly hold the foil to the bottle by placing your hand on top and shake the wort to aerate it.

The Rest: Periodically you will need to re-suspend the yeast. Tighten the cap, shake the bottle and then release the cap ¼ to ½ turn. Listen for a hiss and look for foaming of the wort. This is an indication that your making yeast.

If your using a bottle without a screw cap, then hold the aluminum foil securely and swirl the bottle to re-suspend the yeast. Do not allow the wort to touching the aluminum foil on the top of the bottle and come out and down the outside of the bottle. Look for foaming in the wort. This is your indication that you are making yeast cells.

In both cases, bottle with screw cap or bottle without screw cap, in 24 to 36 hours you should see rapidly rising bubbles and a yeast layer in the bottom of the bottle and, massive foaming when the bottle is swirled.

At this stage of your starter process you are ready to pitch to your cooled aerated wort in your fermenter.

Swirl your starter to suspend the yeast and pour the entire contents of the bottle into your fermenter.

Good luck, my job is done!

The close

This was a fun project to do and with the help of Pilz and his TRUB I was able to complete it quickly. There however was some problems. Two brewers reported problems that could have been attributed to the yeast I sent them. One brewer reported a problem of no activity in the fermenter but had had activity in the starter bottle. It was determined that he had a leak at the lid of his fermenter and wasn't getting airlock activity. That was corrected and he went on to have a fine brew. Nine brewers reported outstanding results and commented on the simplicity and ease of use of the yeast in that format.

The TRUB brewers comments

The attached comments were ether solicitation form the BRC BBS in the form of posts to my questions, e-mailed comments directly to me and from posts on the BrewRatChat.

Recipients reply to the yeast project
Posted by Strange Breewer on December 25, 1998 at 12:28:03:
In Reply to: Trub Yeast Recipients posted by HHHoagie on December 24, 1998 at 14:17:41:

: To all the TRUB participants that received yeast in the mail from me. I would like a little information please about the:
: 1)Condition you received the Mini Starter?
Condition was excellent. No complaints.
: 2)The viability of the yeast(pressure and foaming in the bottle would be your indication of viability)?
Outstanding. Easily as viable as a fresh Wyeast smack pack.
: 3)Ease of use in that format as opposed to the way you have handled yeast in the past?
Nothing could be easier. It worked exactly as advertised.
: 4)Your assessment of how the yeast performed in your fermenter?
Like a bat out of hell. Outstanding.
: 5)And do you think this would be a good way for BRC members to exchange yeast for a single brew session?
Hell, Yes!!!

: I am requesting this information because the owner of the local brewshop sponsors a club and the members as well as the owner was very interested in the outcome of the TRUB project and how the yeast held up in transit as well as the number of different yeast handling techniques it was subjected to from each individual Brew Rat.

: I will be compiling this information as well as the information I have, into a paper for then to further their yeast experiences.
: And who knows, if it looks like something we need at out club site, then it would be available.
: Thanking you in advance
: Bob Hoaglan AKA HHHoagie
By all means, HHHoagie, please post the results. And Thank you for helping to advance the state of Brewing!

Posted by Aidan on December 25, 1998 at 18:26:17:
In Reply to: Trub Yeast Recipients posted by HHHoagie on December 24, 1998 at 14:17:41:
I gotta echo Stranges comments..yeast arrived in excellent condition. Starter took off just fine and the beer fermented and attenuated excellently. Fine job again HHH!

Skot's reply to his infection when asked on the chat.
"welp... I believe that due to the fact that I have never before or since had an "aceto bacter" infection in any of my brews that it was due to either the yeast (perhaps handling after it left your hands eg: high temps in the mail) or a shitty batch of DME that I used to make my starter...

I would like to give your 1056 a go again. I felt very shitty about the whole ordeal"

HHHoagie @ . . . . Sat, Dec 26, 5:15PM CST
Skot, All of those inoculums were done at the same time by the same method of transfer. But you weren't the only one that had trouble so it could have happened here. Heat I would think would only kill the yeast not introduce a bacteria. I need to talk to the other people that had problems. However, I don't think their problems was a bacterial infection?

Strange Brewer @ . . . . Sat, Dec 26, 5:15PM CST
Scot, if you had gotten Acetobacter in the origingal culture, it would have exploded the shipping container. Those things have explosive growth, even faster than yeast. I am certain you would have noticed it by the time you pitched, anyway. No way to mistake that acetic acid.

Skot @ . . . . Sat, Dec 26, 5:17PM CST
I have thought about that too SB..

Skot @ . . . . Sat, Dec 26, 5:18PM CST
See SB... that is what I have been going over for months.... I have had a bout of Lactic hitting batches (luckily all stouts) but never any other nasties

HHHoagie @ . . . . Sun, Dec 27, 4:16PM CST
Hello Steve. Were you one of the ones that had trouble with your TRUB yeast?

steve @ . . . . Sun, Dec 27, 4:18PM CST
It took off slow 3H but I think I should have steped it sooner.Mostly my fault, But it did OK you did a great job of building & shipping

steve @ . . . . Sun, Dec 27, 4:27PM CST
It wasnt me 3H I thought I might, But I believe TD said to check for Krausen it was there changed airlocs and all was fine, must have been a leak!!

E-mail to me from Dan Mistrot, AKA "Pilz"
Hey Hoagie here is my assessment, thanks for the support for the TRUB brew.

1)Condition you received the Mini Starter?
Satisfactory on THUB Yeast, first one you sent for the test had leaked and was almost empty.

2)The viability of the yeast(pressure and foaming in the bottle would be your indication of viability)?
Very little if any pressure was released when opened. It did well after repitch.

3)Ease of use in that format as opposed to the way you have handled yeast in the past?
Ease was equal to others except the actual yeast count is a bit smaller than other media but now I always build up to 2-3 quarts per carboy so it is no more effort that a smack-pak.

4)Your assessment of how the yeast performed in your fermenter?
Yeast performed as well as any comercial yeast media.

5)And do you think this would be a good way for BRC members to exchange yeast for a single brew session?
Mainly good for same yeast brews like we did with the TRUB and for trading yeast or giving away a uncommon/hard to find yeast.
Later brew dude