Yeast immobilization: magic beans of fermentation

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The yeast will definitely die at some point. Whether that happens after many batches or just a few, however, is still a very open question. But, properly handled, yeast can stay alive for quite some time. The fact that they're not reproducing actually means they'll stay healthy a lot longer.
I find that reproductive activity seems to keep me healthy, but maybe that's just me:D
Can't wait for future reports:mug:
 
I find that reproductive activity seems to keep me healthy, but maybe that's just me:D

Maybe it's the same for yeast! Trying to reproduce and failing keeps you healthy; actually budding off a little clone, on the other hand, leaves you scarred and closer to death. :)
 
Subscribed. Super awesome. I am really interested to see how this turns out.

It is a really curious phenomenon. The yeast are trapped in a ball of calcium alginate, but still perform fermentation of sugars. It looks like (from some cursory reading) if you really want to control the permeability of the calcium alginate, you have to do more to control the conditions under which it's formed: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3365340/ however, that's a medical paper so it really could be this simple for brewing purposes.

If it is, I bet those Mupor guys are bummed that you figured this out! :)
 
So wait, if the yeast can't reproduce in these things, won't you just end up with dead yeast cells in a ball of goo? Or are their reproduction rates just hindered?

A lot of people with dead balls of goo pursue adoption. There's always hope.
 
Monday morning update: The beads are fermenting, but man-oh-man are they slow! The comparison here with the control fermentation is interesting.

The beads started fermenting very quickly. I pitched them on Friday night right before I went to bed, and they were already moving by the time I got up six hours later. It seems they've been chugging along at this rate -- but never any faster -- ever since. They've brought the wort down from 1.042 to 1.024 now after about 60 hours. Not terrible, certainly, but slower than I'd expected considering the pitching rate.

The control fermentation, on the other hand, showed no activity at all for roughly 24 hours but then managed to burn through all of the available fermentables by the time I got home from work yesterday (about 48 hours after pitching). This is consistent with what I'd expect for a healthy pitch of s04 in a low-gravity wort at 67º.

The relatively slower ferment of the beads isn't a problem per se, but it does make me curious. It should be fixable. To my mind, there are two possible bottlenecks here:

1) Wort contact - the beads are submerged but floating near the top. I don't suspect that sinking them in a tea strainer or the like would actually improve contact significantly, but mechanical agitation might. Giant stir plate?

2) Bead permeability - I'm going to mix up a few other test batches, perhaps with different ratios of alginate to yeast. I'm just guessing with so much of this, so I can't say for sure what will or won't make a difference.

Anyway, it's all moving along nicely! The bead beer is fermenting slower, but it's still quite clear so I suspect it will be ready more or less as soon as the yeast finishes fermentation.
 
Monday morning update: The beads are fermenting, but man-oh-man are they slow! The comparison here with the control fermentation is interesting.

The beads started fermenting very quickly. I pitched them on Friday night right before I went to bed, and they were already moving by the time I got up six hours later. It seems they've been chugging along at this rate -- but never any faster -- ever since. They've brought the wort down from 1.042 to 1.024 now after about 60 hours. Not terrible, certainly, but slower than I'd expected considering the pitching rate.

The control fermentation, on the other hand, showed no activity at all for roughly 24 hours but then managed to burn through all of the available fermentables by the time I got home from work yesterday (about 48 hours after pitching). This is consistent with what I'd expect for a healthy pitch of s04 in a low-gravity wort at 67º.

The relatively slower ferment of the beads isn't a problem per se, but it does make me curious. It should be fixable. To my mind, there are two possible bottlenecks here:

1) Wort contact - the beads are submerged but floating near the top. I don't suspect that sinking them in a tea strainer or the like would actually improve contact significantly, but mechanical agitation might. Giant stir plate?

2) Bead permeability - I'm going to mix up a few other test batches, perhaps with different ratios of alginate to yeast. I'm just guessing with so much of this, so I can't say for sure what will or won't make a difference.

Anyway, it's all moving along nicely! The bead beer is fermenting slower, but it's still quite clear so I suspect it will be ready more or less as soon as the yeast finishes fermentation.

Interesting stuff. The fermentation rates could also be explained by the inhibition of reproduction by the yeast being encapsulated by the beads. The control started slower because they were in a reproductive phase, but finished faster as there were now increased numbers of cells. In contrast, the bead started faster because they didn't have a stimulus to reproduce (i.e. fresh wort) but could not speed up the fermentation rate because their numbers are somewhat fixed (or decreasing, if you figure in cell death).

It would be interesting to do a cell count, but first you'd have to work out how to get the yeast separated from the balls first. Probably not worth the effort.
 
Monday morning update: The beads are fermenting, but man-oh-man are they slow! The comparison here with the control fermentation is interesting.

The beads started fermenting very quickly. I pitched them on Friday night right before I went to bed, and they were already moving by the time I got up six hours later. It seems they've been chugging along at this rate -- but never any faster -- ever since. They've brought the wort down from 1.042 to 1.024 now after about 60 hours. Not terrible, certainly, but slower than I'd expected considering the pitching rate.

The control fermentation, on the other hand, showed no activity at all for roughly 24 hours but then managed to burn through all of the available fermentables by the time I got home from work yesterday (about 48 hours after pitching). This is consistent with what I'd expect for a healthy pitch of s04 in a low-gravity wort at 67º.

The relatively slower ferment of the beads isn't a problem per se, but it does make me curious. It should be fixable. To my mind, there are two possible bottlenecks here:

1) Wort contact - the beads are submerged but floating near the top. I don't suspect that sinking them in a tea strainer or the like would actually improve contact significantly, but mechanical agitation might. Giant stir plate?

2) Bead permeability - I'm going to mix up a few other test batches, perhaps with different ratios of alginate to yeast. I'm just guessing with so much of this, so I can't say for sure what will or won't make a difference.

Anyway, it's all moving along nicely! The bead beer is fermenting slower, but it's still quite clear so I suspect it will be ready more or less as soon as the yeast finishes fermentation.

Thanks for the update.

I believe Mupor holds their's in a stainless cage under the wort. Here's a pic of what they propose to keep the beads submerged. Looks suspiciously like a strainer and something like a pizza cutter with the rim cut off.

I thought about trying this myself, but I'm not sure what the advantages are yet. Thanks for taking the reigns on this Malfet.

mupor-drop-in-fermenter-cage-59429.jpg


mupor-drop-in-fermenter-cage-2-59430.jpg
 
Interesting stuff. The fermentation rates could also be explained by the inhibition of reproduction by the yeast being encapsulated by the beads. The control started slower because they were in a reproductive phase, but finished faster as there were now increased numbers of cells. In contrast, the bead started faster because they didn't have a stimulus to reproduce (i.e. fresh wort) but could not speed up the fermentation rate because their numbers are somewhat fixed (or decreasing, if you figure in cell death).

It would be interesting to do a cell count, but first you'd have to work out how to get the yeast separated from the balls first. Probably not worth the effort.

Right, that's why I estimated a fermentation-final cell count and used that as my bead pitching rate. In approximate terms, there should be about the same number of cells in each batch now.

Thanks for the update.

I believe Mupor holds their's in a stainless cage under the wort. Here's a pic of what they propose to keep the beads submerged. Looks suspiciously like a strainer and something like a pizza cutter with the rim cut off.

I thought about trying this myself, but I'm not sure what the advantages are yet. Thanks for taking the reigns on this Malfet.

If there's no impact on flavor, I'd seriously consider using these regularly. The beer is completely clear even now as it ferments, and handling the yeast is very easy. The next question will be how many batches a wad of beads will ferment before it starts getting sickly. If it's dozens, this would be a huge time saver. If it's just one or two, though, ....meh.
 
Hey, here's a crazy idea:

Think of a cake piping tools
sku_155599_1.jpg


Where instead of creating hundreds of "yeast balls" one creates one (or several) long star-shaped yeast-strings/snakes that can be easily fished out post fermentation.

I'll be buying the necessary tools to perform my own experiments.
Maybe even use food coloring in each "yeast-snake" to be able to distinguish between different yeasts/brett/lacto/pedio that will be fermenting the beer in question.

Now, who's with me? :D
 
Hey, here's a crazy idea:

Think of a cake piping tools
sku_155599_1.jpg


Where instead of creating hundreds of "yeast balls" one creates one (or several) long star-shaped yeast-strings/snakes that can be easily fished out post fermentation.

I'll be buying the necessary tools to perform my own experiments.
Maybe even use food coloring in each "yeast-snake" to be able to distinguish between different yeasts/brett/lacto/pedio that will be fermenting the beer in question.

Now, who's with me? :D


You'd be losing a lot of surface area this way, which is trouble for diffusion rates. This stuff's actually pretty easy to work with. Dripping the beads into the calcium solution only takes a couple of minutes really, and I'll be able to fish the beads back out with not much more than a strainer at the end.
 
It would be really neat if the beads did ferment faster and allow the beer to clear in around 1.5 weeks instead of the 3 weeks that is often tossed around here as the minimum for primary fermentation. The time saving would have some value to me.
 
You'd be losing a lot of surface area this way, which is trouble for diffusion rates. This stuff's actually pretty easy to work with. Dripping the beads into the calcium solution only takes a couple of minutes really, and I'll be able to fish the beads back out with not much more than a strainer at the end.

Thanks for the reply, it makes sense.

However, it was exactly the low(est) "surface area / volume ratio" property of spheres that made me think of a star shaped "yeast-string" to maximize surface area.

On the piping tool pic, look at the left table (pink) second top of the right column tool. I think it would be ideally shaped for such a task.
Of course, all I have to do convince myself is to do it. ;)

I was thinking maybe 10cm long snakes (say 10 billion cells each) and if your recipe calls for 250B cells, you drop 25 of those bad boys in there and be done...

Hmmm....
 
It would be really neat if the beads did ferment faster and allow the beer to clear in around 1.5 weeks instead of the 3 weeks that is often tossed around here as the minimum for primary fermentation. The time saving would have some value to me.

There's two things here, though, right? Though I was complaining that the beads were working slowly a few posts ago, the reality is that I'm 2/3rds through fermentation in about sixty hours. If there's a time savings to be had here, it's going to be not from fermentation speed but clearing speed. In the bead beer, there's nothing to clear. It looks like normally clear beer right now and it's still actively fermenting.

What about suspending some stainless steel shot or other weights inside the beads?

Certainly, though that'd be quite a bit more work and I'm a very lazy man. I think you'd have to use molds somehow. In any case, I'm not sure that weighting the beads down will significantly improve surface contact. If I were to try to weight the yeast somehow I'd probably use something like what passedpawn post a picture of.

Any current visual pron available?

I'll post something when I get home tonight. The thing is, though, the control looks like a normal beer ferment and the experimental looks just like it did when it started. Aside from a very small amount of gas output, there are very few signs of fermentation in the bead jar.
 
I remember reading somewhere in Mupor's thread that you had to pitch as much bead-suspended yeast as you would end up with in a regular fermentation.

and definitely subbed.

because SCIENCE!
 
Thanks for the reply, it makes sense.

However, it was exactly the low(est) "surface area / volume ratio" property of spheres that made me think of a star shaped "yeast-string" to maximize surface area.

On the piping tool pic, look at the left table (pink) second top of the right column tool. I think it would be ideally shaped for such a task.
Of course, all I have to do convince myself is to do it. ;)

I was thinking maybe 10cm long snakes (say 10 billion cells each) and if your recipe calls for 250B cells, you drop 25 of those bad boys in there and be done...

Hmmm....

Certainly...I like the color idea. Assuming these things keep for reasonably long periods of time and reasonably high numbers of batches (and I consider that a very big assumption at this point), it'd be nice to see beads of all different colors sitting in your fridge.

Just to clarify, though, a sphere only has the lowest surface area / volume ratio for a fixed quantity of substance. 10 grams of tiny spheres will have significantly more surface area than 10 grams rolled into a snake.

It would be beneficial to have "frills" on droplets, but I doubt you'd get that effect with a icing bag. Soon as the goop hits the calcium solution, its surface tension pulls it into a sphere shape pretty much no matter how it started. Worth a try, though!
 
Thanks for the reply, it makes sense.

However, it was exactly the low(est) "surface area / volume ratio" property of spheres that made me think of a star shaped "yeast-string" to maximize surface area.

On the piping tool pic, look at the left table (pink) second top of the right column tool. I think it would be ideally shaped for such a task.
Of course, all I have to do convince myself is to do it. ;)

I was thinking maybe 10cm long snakes (say 10 billion cells each) and if your recipe calls for 250B cells, you drop 25 of those bad boys in there and be done...

Hmmm....

There's a white paper on the interenet somewhere that did lab studies with different bead sizes (and yeast and the alginate beads). The smaller the beads were the better. They used an "electrostatic syringe" to create very small beads.

There is a necessary transfer of sugars into the bead, and CO2 out, that limits the speed of the fermentation. Reducing the bead size might improve this.
 
Certainly...I like the color idea. Assuming these things keep for reasonably long periods of time and reasonably high numbers of batches (and I consider that a very big assumption at this point), it'd be nice to see beads of all different colors sitting in your fridge.

Just to clarify, though, a sphere only has the lowest surface area / volume ratio for a fixed quantity of substance. 10 grams of tiny spheres will have significantly more surface area than 10 grams rolled into a snake.

It would be beneficial to have "frills" on droplets, but I doubt you'd get that effect with a icing bag. Soon as the goop hits the calcium solution, its surface tension pulls it into a sphere shape pretty much no matter how it started. Worth a try, though!

 
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If this works, I'm going back to my stir plate idea for primary fermentation since I won't have to fight the fallen yeast. Since I'm under positive pressure constantly, I wouldn't have the O2 going into the fermenting beer like in a starter to worry about and it would move the beer around the beads for greater yeast to beer contact. I'm in a Sanke so I plan on side wall stir bar agitation with a more spherical type of stir bar. My thoughts go to containing the beads in larger tea balls so they don't have any possibility of going into my dip tube when transferring to my serving keg.

One question that I am worrying about if this works: What about lagers? For ales floating beads is great since they are at the top, but what about bottom fermenting yeast strains? Would circulating via stir bar overcome this no matter the strain, or would you have to contain or sink the beads for lager?

Man this is a great experiment and I can't wait to see when tasting comes into the equation.
 
One question that I am worrying about if this works: What about lagers? For ales floating beads is great since they are at the top, but what about bottom fermenting yeast strains? Would circulating via stir bar overcome this no matter the strain, or would you have to contain or sink the beads for lager?

I don't think the yeast are smart enough to know whether they're at the top or the bottom. Top fermenting yeast just naturally float up while they are actively fermenting, while bottom fermenting yeast naturally sink. Correct me if I'm wrong.
 
If this works, I'm going back to my stir plate idea for primary fermentation since I won't have to fight the fallen yeast. Since I'm under positive pressure constantly, I wouldn't have the O2 going into the fermenting beer like in a starter to worry about and it would move the beer around the beads for greater yeast to beer contact. I'm in a Sanke so I plan on side wall stir bar agitation with a more spherical type of stir bar. My thoughts go to containing the beads in larger tea balls so they don't have any possibility of going into my dip tube when transferring to my serving keg.

One question that I am worrying about if this works: What about lagers? For ales floating beads is great since they are at the top, but what about bottom fermenting yeast strains? Would circulating via stir bar overcome this no matter the strain, or would you have to contain or sink the beads for lager?

Man this is a great experiment and I can't wait to see when tasting comes into the equation.

I don't imagine it would make a difference for lagers, at least as I understand it. The top versus bottom thing is a consequence of a bunch of different factors, but I've never seen anything to suggest that it's necessary.

I'm very skeptical that this will produce quality results. My reasoning for that is simple: alginate immobilization is a well known thing. Pretty much any college-level biochem class will play around with this. There are some significant advantages, particularly at the commercial scale. Yet, I've never heard of a commercial brewery actually going this route. I've got to imagine that if AB-Inbev isn't doing this, it's not because they haven't heard of it.

But, it's fun to play with. I'm looking forward to tasting too, though there's a long way to go before I will feel comfortable declaring one way or the other. Considering how cheap and easy this is, I'm hoping others will give it a shot once I've run my test batch through. It will take a heck of a lot more than a few test batches for me to start using something like this regularly.
 
Just to clarify, though, a sphere only has the lowest surface area / volume ratio for a fixed quantity of substance. 10 grams of tiny spheres will have significantly more surface area than 10 grams rolled into a snake.

Good point.

Soon as the goop hits the calcium solution, its surface tension pulls it into a sphere shape pretty much no matter how it started

Good to know, I've never used this stuff.
 
I don't think the yeast are smart enough to know whether they're at the top or the bottom. Top fermenting yeast just naturally float up while they are actively fermenting, while bottom fermenting yeast naturally sink. Correct me if I'm wrong.

That's what I was thinking and hoping for. Now does anyone see a problem with containing them if a stir bar is agitating the active fermentation? Remember, I'm sealed up so no worry of O2 like goes on with a starter.
 
That's what I was thinking and hoping for. Now does anyone see a problem with containing them if a stir bar is agitating the active fermentation? Remember, I'm sealed up so no worry of O2 like goes on with a starter.

Nope! No problem I can see. It might even help with ester development, as (I believe) CO2 saturation inhibits Acetyl CoA production in some important way that I've read about but don't fully understand. If you can keep things more evenly distributed, that might help. I've heard smart people argue that it's actually this that makes stirplates useful during yeast propagation, rather than the other stuff we usually think of.

/end wild speculation
 
MalFet, I wonder if this is how they utilize yeast in major breweries for what they call accelerated maturation? I know Bud uses the beechwood chips to give a large surface area for the yeast to clean the beer and mature it as fast as they do, but i have read other use pushing the beer through a area of contained yeast. I wonder if a container filled with these beads would be something similar/same? I know lager breweries are the ones mostly mentioned when talking accelerated maturation.
 
I would be very interested to see you put some of the fermented magic bean beer under a microscope to see what's in there, side-by-side with some of the control batch.
 
This is really cool. I'm awaiting the taste results.

Certainly...I like the color idea. Assuming these things keep for reasonably long periods of time and reasonably high numbers of batches (and I consider that a very big assumption at this point), it'd be nice to see beads of all different colors sitting in your fridge.

yes yeast colors

Just to clarify, though, a sphere only has the lowest surface area / volume ratio for a fixed quantity of substance. 10 grams of tiny spheres will have significantly more surface area than 10 grams rolled into a snake.

your statement is correct "lowest surface area/volume" but your conclusion is opposite the statement. This means that a sphere of volume V will have the smallest surface area SA of any shape, not the largest.

Frankly it doesn't matter as the concern is to have a easiest way to make them (spheres) and just put more in. And I think the smallest size (Volume or dimension) is desireable.

I'm wondering about permiablity of the wort beyond the surface- are these pouruse enough? Otherwise you end up with only the surface yeast doing any work and there could be far less yeast doing the work.
 
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