Shaken, not Strirred

Share your experiences of using brewing yeast.
Post Reply
YeastWhisperer

Shaken, not Strirred

Post by YeastWhisperer » Sun Mar 29, 2015 12:59 am

Contrary to what most home brewers have been led to believe, stir plates were not designed to aerate cultures. They were designed to keep cells from multi-cellular eukaryotes (yeast cells are single-cell eukaryotes) from clumping during a laboratory process known as suspension cell culturing. FLO is the name for the set of genes that control flocculation in yeast. Most brewing yeast strains are NewFlo strains, which means that they naturally remain in suspension until mannose, glucose, maltose, sucrose, and maltotriose have been reduced to a genetically set level; hence, starters do not need to be stirred to keep the viable yeast cells in suspension. Additionally, spinning a starter fast enough to aerate the medium during the lag phase causes the yeast cells to experience shear stress, which is why stirred starters often smell and taste foul.

I covered a yeast starter method that I have used for over two decades in gory detail over on the AHA forum (I post as S. cerevisiae on the that forum). My starter method was given the name the James Bond Method by the one of the forum members because I refer to it as the shaken, not stirred method (a.k.a. well-shaken starter). This method is a low-tech, low-cost way to make a high-performance starter. All one needs to make a well-shaken starter is a sanitizable vessel that is at least four times the volume of the starter being prepared, a sanitizable screw-on cap for the vessel, and a funnel. I do not know if anything comparable is available in the UK; however, one U.S.-gallon glass jugs (demijohns in UK speak) are plentiful in the United States. Home brew supply stores sell plastic replacement caps for these jugs that can be sanitized (38mm polyseal screw top caps). If one has money to burn, a 5L borosilicate glass media bottle like I currently use is a very nice toy. However, 5L media bottles can cost prohibitive when purchased new. I acquired my 5L media bottle as unused laboratory surplus, and it was not cheap. I used a 1-gallon glass jug for a very long time before switching over to using a 5L media bottle.

Preparing the starter medium (a.k.a. starter wort)

The starter medium is prepared like one would prepare a starter any other way. A 10% weight/volume solution is made by mixing 100 grams of pale DME into a little more than 1L of water. The goal here is to end up with 1L of media after the solution has been boiled and cooled to room temperature. I boil the solution for 15 minutes in a 3-quart stainless steel sauce pan (A U.S. quart is slightly smaller than a liter). The media is chilled in the sauce pan with the cover affixed using an ice water bath in my kitchen sink.

Sanitizing the starter vessel, screw-on cap, and funnel

The starter vessel, screw-on cap, and funnel should be sanitized while medium is boiling and chilling. While I use bleach and StarSan, feel free to use your preferred sanitizer. It is critical that the funnel is sanitized as well, and that one does not touch the inside surface of the funnel after it has been sanitized.

Note: One thing that I like to teach home brewers is to get into the habit of wiping the lip over which yeast or nutrient will be poured with an alcohol saturated cotton ball before decanting yeast, medium, or supernatant (supernatant is the clear liquid that lies above the solids in a starter, yeast crop, or a batch of beer). Wild microflora (yeast, mold, and bacteria) rides through the air on house dust. What we want to do is ensure that we do not drag any dust that may have come to rest on the pouring lip of the container that we are decanting into a vessel in which we intend to grow a culture or ferment a batch of beer. This precaution makes sense If one thinks about what a nurse or doctor does before giving one an injection. The reason why a doctor or a nurse cleans an injection site with an alcohol wipe before giving one an injection is to prevent the needle from dragging microflora that is on one’s skin into the injection site.

Pouring the starter medium

After placing the funnel in the starter vessel, one should wipe the pouring lip of the sauce pan in with an alcohol saturated cotton ball before pouring the starter medium into the starter vessel. I use 70% or 90% isopropyl alcohol. I used to use 95% ethanol (a.k.a. grain alcohol). However, my state outlawed its sale due to teenagers and young adults abusing it. Any 140 proof or better clear spirit will work. Please do not use methylated spirits.


Inoculating the starter medium

If using a White Labs vial, wipe the pouring lip of the vial with an alcohol saturated cotton ball before pouring the yeast culture into the starter vessel. If using a Wyeast smack pack, wipe the outside of the smack and the blades of the pair of scissors that one is using to cut a corner off of the smack pack with an alcohol saturated cotton ball before making the cut, and wipe the cut edge of the smack pack with an alcohol saturated cotton ball before pouring the contents of the smack pack into the starter vessel.


Caping and shaking

Here’s where my method differs from the way the average home brewer makes a starter. The reason why a vessel with a screw-on cap is necessary with this method is because one is going to shake the culture very vigorously for about a minute. I usually tell brewers to shake the starter vessel like it owes you money (think mafia enforcer). The goal here is to attempt to turn the media into foam. That's why the vessel has to be at least four times the volume of the starter. One should then allow the starter to sit for around thirty minutes before loosening the cap to allow the foam to drop.

A well-shaken starter in a 5L media bottle

Image

Pitching the starter

Pitching is one area where most home brewers get it completely wrong. A starter is not a small batch of beer. It is a yeast biomass growth medium. The goal here is to grow the culture to maximum cell density and then pitch it. Maximum cell density occurs at high krausen. Beyond that point, all cell reproduction is for replacement only. Yeast taken at high krausen is much healthier than yeast that is taken from a sedimented starter or batch of beer. That’s why traditional breweries crop yeast at high krausen. Allowing a starter to ferment out and settle places the cells in the yeast equivalent of hibernation where they will have to undo survival-related morphological changes that occurred at the end of fermentation as well as completely replenish their ergosterol and unsaturated fatty acid reserves after being pitched.

High krausen should occur within 12 to 18 hours after pitching the starter. The yeast biomass grows exponentially, not linearly. The yeast cell count grows at a rate of 2^n, where the symbol “^” means raised to the power of, and n equals the number of minutes that have elapsed since the end of the lag phase divided by 90; hence, the difference in propagation time between 200B cells and 400B cells can be as little as 90 minutes.


British Versus American Pitching Rates

If one believes the yeast calculators found on American sites, one will end up growing 2 to 3 liter starters for 23L batches. Frankly, the guys who wrote this code know more about coding than they do about yeast. No two yeast cultures behave the same when pitched, and no two yeast cultures require the same pitching rate. The only thing that will teach one the proper pitch rate for any given strain is experience with the strain in one’s brew house. Additionally, it is often desirable to underpitch in order to achieve a desired flavor profile. British styles benefit from underpitching. I often pitch as little as 60B cells into 19L of wort when fermenting normal gravity beer (i.e., < 1.065). Wyeast 1768, which is allegedly Young’s stain, performs much better when pitched at a rate of 3B cells per liter than at a rate of 10B cells per liter when fermenting normal gravity ale. It produces what I like to refer to as the British lollipop ester when the beer is young. This strain produces a delightfully fruity and malty pint when used with a grist that is composed mostly of British pale malt.
Last edited by YeastWhisperer on Mon Aug 17, 2015 2:11 pm, edited 5 times in total.

jaroporter
Drunk as a Skunk
Posts: 996
Joined: Sat Jul 21, 2012 11:12 pm
Location: Garden of England

Re: Shaken, not Strirred

Post by jaroporter » Sun Mar 29, 2015 8:53 am

that is a fantastic post, YeastWhisperer! very informative and simplifies the whole procedure. and makes a lot of sense regards pitching practises :) thanks for that!
dazzled, doused in gin..

Matt12398

Re: Shaken, not Strirred

Post by Matt12398 » Sun Mar 29, 2015 10:06 am

That's really interesting. I pitch at high krausen because it's easier and always thought that I was cutting corners by not allowing to ferment out. Pleased to hear I'm wrong.

If brewing a lager though with a large starter, the amount of spent starter medium is going to be proportionately a lot higher in relation to the total beer volume. What is best practice here?

Pegasus
Steady Drinker
Posts: 56
Joined: Fri Jan 02, 2015 5:24 pm
Location: Garden of Eden, Kent

Re: Shaken, not Strirred

Post by Pegasus » Sun Mar 29, 2015 2:00 pm

Excellent and thorough article - the info on pitching rates is particularly interesting.

For what it's worth, many years ago research showed that 70% ethanol was the most effective concentration for surface decontamination of vegetative organisms (yes, better than 95% :shock: ). Many labs (inc hospital) in the UK tend to use 70% denatured alcohol (aka Meths - it's duty free and cheap) and it's usually supplied by the pharmacy. The difference between hospital meths and shop bought is the latter has a colourant and (I think) some other foul smelling additive to dissuade imbibing (methanol - a constituent at about 10% - also smells foul). Can't see a reason for not using it as a surface decontaminant at 70% - which is what I do - and letting it evaporate before cutting open/pouring.

Alternatively, you can use a flame to surface sterilise surfaces (scissors, lips of glass bottles). I use a version of a kitchen blow torch.

As stated, important thing is aseptic technique as much as possible. And, stating the obvious, I wouldn't advise doing the dusting/vacuuming just just before or during brew prep (as if you'd want to :wink: )

Paul

User avatar
Wonkydonkey
Drunk as a Skunk
Posts: 847
Joined: Sat Mar 01, 2014 9:37 am
Location: In the Stables

Re: Shaken, not Strirred

Post by Wonkydonkey » Mon Mar 30, 2015 1:26 am

The IMS (industrial methylated spirit) that I used to use is 1% methanol, the real stuff ( 100% ethanol ) was in the locked cupboard.
yeh the colourant/flavouring (iirc, biterex) in the meths we buy is to stop peeps/kids drinking it,
To Busy To Add,

YeastWhisperer

Re: Shaken, not Strirred

Post by YeastWhisperer » Mon Mar 30, 2015 2:34 am

Matt12398 wrote:If brewing a lager though with a large starter, the amount of spent starter medium is going to be proportionately a lot higher in relation to the total beer volume. What is best practice here?
I do not double my pitching rate when making a lager. I have found that pitching a well-shaken starter at high krausen is like pitching the yeast equivalent of special forces. The only time that I double my pitching rate is when pitching a beer with a gravity of 1.070+, and I account for the dilution by boiling my wort down slightly. I always take my gravity reading after pitching.
Last edited by YeastWhisperer on Mon Mar 30, 2015 6:22 pm, edited 1 time in total.

YeastWhisperer

Re: Shaken, not Strirred

Post by YeastWhisperer » Mon Mar 30, 2015 3:12 am

Pegasus wrote:For what it's worth, many years ago research showed that 70% ethanol was the most effective concentration for surface decontamination of vegetative organisms (yes, better than 95% :shock: ). Many labs (inc hospital) in the UK tend to use 70% denatured alcohol (aka Meths - it's duty free and cheap) and it's usually supplied by the pharmacy. The difference between hospital meths and shop bought is the latter has a colourant and (I think) some other foul smelling additive to dissuade imbibing (methanol - a constituent at about 10% - also smells foul). Can't see a reason for not using it as a surface decontaminant at 70% - which is what I do - and letting it evaporate before cutting open/pouring.
I use 70% (140 proof) for wiping surfaces and 90-95% for surfaces that will be wiped and flamed because it burns much better. I usually start a culturing session by flaming a nichrome loop until it is red hot before allowing it to cool slightly and quenching it in culture tube full of 91% isopropanol or 95% ethanol (yes, it was spooky the first time that I did it). From that point forward, the loop remains in the alcohol bath between uses. All I have to do withdraw the loop from tube, burn off the alcohol in a spirit lamp or a bunsen burner, and then perform my transfer. Using this technique prevents me from having to pick an area on a plate or a slant to cool the loop before taking a sample.
As stated, important thing is aseptic technique as much as possible.
Learning aseptic technique is one the best things that a brewer can do to improve his/her beer. The technique outlined above grew out of basic laboratory aseptic transfer technique. I have maintained a yeast bank since I started brewing in early 1993. Being able to maintain a yeast bank at that point in time was much more critical than it is today. However, being able to plate and slant yeast is still a valuable skill because it opens up the culture collections as well as being able to collect and isolate yeast cultures from bottle dregs, brewery crops, or even wild samples.

By the way, we use isopropanol for medical purposes. I have never seen anything, but industrial-grade methylated ethanol in the United States. I used to be able to purchase 95% untainted ethanol (known in the U.S. as grain alcohol) in liquor stores until my state government outlawed it. The most commonly available brand of 95% ethanol was Everclear (http://en.wikipedia.org/wiki/Everclear_%28alcohol%29).
Last edited by YeastWhisperer on Mon Aug 17, 2015 2:24 pm, edited 3 times in total.

User avatar
Hanglow
Under the Table
Posts: 1399
Joined: Wed Nov 28, 2012 6:24 pm

Re: Shaken, not Strirred

Post by Hanglow » Mon Mar 30, 2015 6:16 pm

Great, informative post YeastWhisperer =D>


Do you have pitching rates for other yeasts that you use? Such as US-05, Nottingham, S-04 and the other popular strains?

legion
Hollow Legs
Posts: 423
Joined: Mon Feb 16, 2009 1:55 pm

Re: Shaken, not Strirred

Post by legion » Mon Mar 30, 2015 6:39 pm

Hi yeast whisperer, do you only shake the starter once in the 12-18 hours?
Maidstone Brewers Homebrew Meets - Next Meet 14:00 Wednesday 27 December
https://Twitter.com/maidstonebrews https://www.facebook.com/groups/maidstonebrewers

YeastWhisperer

Re: Shaken, not Strirred

Post by YeastWhisperer » Mon Mar 30, 2015 7:21 pm

My pitching rates for normal ale strains are 3 to 5 billion cells per liter for normal gravity British-style ales and 5 to 8 billion cells per liter for normal gravity American-style ales. While phenols, diketones, and some higher alcohols are generally not welcome, ale is not supposed to be 100% ester free. Esters are the key to ale tasting like ale.

With that said, you would be surprised at the range of cell counts that will produce a nicely flavored ale from a fermentation point of view. The key to off-flavor-free fermentation are culture management, aeration, and fermentation control (i.e. attemperation). While the quality of dry yeast is light years better than it was when I first started brewing, it still pales in comparison to a well-managed liquid culture or a culture grown from a slant. Aerobic propagation in a bioreactor coupled with fluid bed drying appears to alter the performance of the reference strains. For example, I have yet to drink a beer that was made with US-05 that is as off-flavor free as one that was fermented from a well-managed BRY 96 culture.

As an aside, Siebel BRY 96 is the culture that we know today as "Chico," Wyeast 1056, White Labs WLP001, and US-05. It is one of two cultures that came from the defunct Ballantine Brewery in Newark, New Jersey (America's last surviving ale brewer before the craft brewing movement). The other Ballantine strain is believed to be Siebel BRY 97, which most home brewers know as Lallemand BRY 97. The modern incarnation of BRY 97 is the Anchor Liberty Ale strain. There is evidence to support that BRY 96 was not originally used to produce ale, which would explain its cold tolerance. Ballantine deposited the following cultures in the USDA/ARS NRRL Collection:

NRRL Y-7407
Accession numbers in other collections: Lange 2
Isolated from (substrate): BR, Beer pitching yeast
Substrate location: Ballantine Brewery, New Jersey, USA
Comments: ID from 26S renal partial sequences.

NRRL Y-7408
Accession numbers in other collections: Lange 4
Isolated from (substrate): BR, Ale pitching yeast
Substrate location: Ballantine Brewery, New Jersey, USA
Comments: ID from 26S rDNA partial sequences

It is an open secret that Siebel BRY 96 is a Ballantine yeast strain. It is also an open secret that Sierra Nevada acquired "Chico" as BRY 96 from the Siebel Institute (Lallemand purchased the Siebel Institute in 2000). Like the NCYC, sequential accessions within a U.S. culture collection often came from the same brewery. If Ballantine deposited BRY 96 and BRY 97 in the Siebel Culture Collection in the same order that they deposited Y-7407 and Y-7408 in the NRRL, or Siebel acquired the cultures from the NRRL, then BRY 96 = Y-7407 and BRY 97 = Y-7407, which makes BRY 96 the mock lager yeast strain (i.e., Ballantine's "beer" strain) and BRY 97 the ale yeast strain (which explains its lack of cold tolerance).

Here's what the Ballentine Ale strain looked like when it was used in an open fermentation vessel:

Image

I have used BRY 96 and BRY 97, and the yeast strain employed in the photo shown above is definitely not BRY 96. On the other hand, BRY 97 is a flocculent top-cropping strain. Look at the size of the BRY 97 flocs in one of my primary fermentation vessels after racking:

Image
Last edited by YeastWhisperer on Mon Aug 17, 2015 2:20 pm, edited 1 time in total.

hambrook
Piss Artist
Posts: 130
Joined: Fri Dec 19, 2014 9:22 am
Location: Emsworth, Hampshire

Re: Shaken, not Strirred

Post by hambrook » Tue Apr 28, 2015 2:32 pm

I did not see an answer to this question: Hi yeast whisperer, do you only shake the starter once in the 12-18 hours?
- Former owner of The Emsworth Brewhouse -
Now back to home brewing of a Braumeister 50L

YeastWhisperer

Re: Shaken, not Strirred

Post by YeastWhisperer » Tue Apr 28, 2015 4:39 pm

Yes, the starter only needs to be shaken one time. However, it is shaken with a purpose. The idea is to attempt to turn the wort into mostly foam, which is why one should use a vessel with a volume that is at least four times the starter volume. Foam provides a large surface area for the movement (diffusion) of oxygen into the wort. That's basically the key to why this method works so well for being so low-tech.

hambrook
Piss Artist
Posts: 130
Joined: Fri Dec 19, 2014 9:22 am
Location: Emsworth, Hampshire

Re: Shaken, not Strirred

Post by hambrook » Tue Apr 28, 2015 4:42 pm

Thanks YeastWhiperer - but to clarify the yeast is already suspended in the worst whilst you are shaking it like made for that 1 minute duration?
- Former owner of The Emsworth Brewhouse -
Now back to home brewing of a Braumeister 50L

User avatar
Jocky
Even further under the Table
Posts: 2738
Joined: Sat Nov 12, 2011 6:50 pm
Location: Epsom, Surrey, UK

Re: Shaken, not Strirred

Post by Jocky » Mon May 11, 2015 11:35 am

Additional question - do you crash chill the starter at high krausen so that you can decant off the supernatant, or just assume that at only 1 litre, your starter is small enough to not have any ill effects on your finished beer?
Ingredients: Water, Barley, Hops, Yeast, Seaweed, Blood, Sweat, The swim bladder of a sturgeon, My enemies tears, Scenes of mild peril, An otter's handbag and Riboflavin.

barry44

Re: Shaken, not Strirred

Post by barry44 » Mon May 11, 2015 2:49 pm

Hi, would I be able to use a plastic bottle in place of the demijohn?

I use 5 litre ones from tesco for my starsan.

Post Reply