R.O H20 cell damage to yeast?

[Bubbles2]

Has anyone found a definite answer in regards to R.O H20 and the water's cell wall?

I am curious to find out if R.O damages the cell wall? I have read 5-8 articles with citations and so forth but have come up empty on if indeed Osmosis creates damage to the water's cell wall and if removing it's solutes, albeit mine re-mineralizes the H20 before it comes out of the tap at about 37ppm
Does this leave my water's cell subject to Hypotonic or Hypertonic or because it is re mineralized "adding Solutes" is it now Isotonic and is there any effect on the Yeast's cell because of it?

Eg., The Yeast is now subject to hypotonic reaction causing it to implode and shorten the yeast's life and harvesting from Post brew of RO H20 leave me with damaged Yeast cells to re-pitch after rinsing and starting?

Why is this in a brewing forum?

1. There are some brilliant minds brewing beer who indeed know of a resource(s) to find that information out. I've spent a couple of hours, and a few times searching, reading, and now I ask here maybe someone has found the answer?...with Citations

2. Yeast uses the H20 cell in it's attenuation process and dictates the life/durability of Yeast.

3. Harvesting Yeast from a Post Wort batch that used R.O H20


Finally, I have started an experiment harvesting Post Wort batch Yeast (with the same ingredients, conditions) and indeed saw full attenuation and F.G in 15 days as the mother batch of Omega Labs yeast NW Pacific did with R.O H20 it was in.
I'm now waiting the 2-3 weeks for the taste test of a re-pitched post batch yeast or 2nd gen....To see if there is any noticeable 'off tastes' where I can compare first batch with second at the same time.

*Note when Rinsing and starting I do NOT use R.O water only "refrigerator" charcoal filtered water (leaving Fluoride CZ6 and some arsenic in the Municipal water; NOT R.O h20) I do this as I "believe" when creating the starter, the yeast cells need all the help they can get when reproducing to be an ample amount to re-pitch.

 

[MaxStout]

Has anyone found a definite answer in regards to R.O H20 and the water's cell wall?

I am curious to find out if R.O damages the cell wall? I have read 5-8 articles with citations and so forth but have come up empty on if indeed Osmosis creates damage to the water's cell wall and if removing it's solutes, albeit mine re-mineralizes the H20 before it comes out of the tap at about 37ppm
Does this leave my water's cell subject to Hypotonic or Hypertonic or because it is re mineralized "adding Solutes" is it now Isotonic and is there any effect on the Yeast's cell because of it?
...

Water has a cell wall?

Perhaps you meant cell wall water content?

Perhaps you could post links to some of those citations? I have never heard of such a thing, but I'm curious. There is some disagreement about rehydrating yeast using purified water, due to osmotic pressure on the cells. But that term osmotic is referring to something completely different from the "osmosis" used in filtering water in an RO system.

 

[mongoose33]

Honestly, I have no idea what you're asking nor what might have given you the idea that RO water has a negative effect on yeast.

I've been using RO water for a long time and I've never noticed any kind of issue. When I make a starter I begin with RO water, add DME, a pinch of yeast nutrient, and go.

Most of my brewing water is RO.

About the only issue I might see relevant to this is rehydrating dry yeast. Is this what you're concerned with? If so, Fermentis says to not use demineralized water to rehydrate.

 

[Bubbles2]

@Max Stout, thanks for pointing out that water is a molecule, I was confused as I searched. I have changed my search and learned the answer. Thank you.

In short-"An RO membrane rejects contaminants based on their size and charge. Any contaminant that has a molecular weight greater than 200 is likely rejected by a properly running RO system (for comparison a water molecule has a MW of 18)"
On that note of size I do not see how the molecule would become deformed.

Why the Post? I was sent on a 'goose chase' from someone who Pm'd me here and did not have a grasp on what they were sharing. I was told I need to be careful in regards to Hyper, Hypo and Iso Tonic in regards to the Yeast cell. However in light of RO only catching 200 and H20 is an 18 MOLECULE I see no damage should occur. For a little Biology 6 minutes of fun...

https://www.khanacademy.org/science...ic-isotonic-and-hypertonic-solutions-tonicity

@Mongoose, that is good to hear that you are using R.O and assume you are re using yeast post wort batch.

Thanks again.

 

[xico]

It's an interesting question because the water matrix is seeking equilibrium. The reverse extreme is a high-gravity wort, where the density of the water matrix is much higher and so the yeast have to expend energy so as not to lose its inner-cellular water to homogenization. Proper lab water is not safe to drink because the capacity to "fit" compounds into it means it can strip the calcium out of your teeth.

I'm not asserting this is bad for your yeast but it's an interesting question not without merits. One cool experiment would be to hydrate some yeast in RO water and then crash the yeast and decant to send out for testing. Compare it to your control of non-yeast water in an ion test. If you can measure yeast viability at hydration and then again post decant might add more data to look at. 100 bucks and you may have an answer we hadn't considered before. I think you can crowdfund something small like that.

 

[Miraculix]

Has been done and discussed here before. Ro and distilled water kills yeast.

 

[Bubbles2]

Has been done and discussed here before. Ro and distilled water kills yeast.

NO it does not kill it, it could starve it or leave it without the minerals it needs if indeed you use (Zero) ppm H20. If you did not rebuild the H20 or re mineralize it. I use R.O H20 and am re using yeast from a post wort batch that was made with R.O H20. I have batch bumpin along using dry Safale 05 and R.O without using a starter with a OG of 1067. I have been reaching projected attenuation if not better within 2 weeks using Omega, White liquids and R.O albeit re-mineralized with a ppm of 37 due to minerals it adds of a FG of 1011 - 1014 pending on the batch.

@xico I do not think the R.O Membrane is small enough to damage the H20 Molecule aforementioned above.

 

[day_trippr]

A couple of years ago an HBT member posted a video of a yeast cell exploding in distilled water due to excessive trans-membrane osmotic pressure. Was pretty cool...

Cheers!

 

[Miraculix]

NO it does not kill it, it could starve it or leave it without the minerals it needs if indeed you use (Zero) ppm H20. If you did not rebuild the H20 or re mineralize it. I use R.O H20 and am re using yeast from a post wort batch that was made with R.O H20. I have batch bumpin along using dry Safale 05 and R.O without using a starter with a OG of 1067. I have been reaching projected attenuation if not better within 2 weeks using Omega, White liquids and R.O albeit re-mineralized with a ppm of 37 due to minerals it adds of a FG of 1011 - 1014 pending on the batch.

@xico I do not think the R.O Membrane is small enough to damage the H20 Molecule aforementioned above.

Read the post above.nothing to add.

If you feel fancy, put a piece of potato over night into distilled water and another into tap water.

See what happens. Same happens with yeast.

 

[Bubbles2]

Is that because the distilled H20 is void of solutes? My R.O H20 is rebuilt with minerals... I could see how H20 that is void of solutes and how it could indeed make the yeast cell hypertonic and explode. I'd need to see some papers on it, with citations, not hearsay.

-Do your potato test with rebuilt H20 like many larger brewers use, I use, and have had nothing negative thus far using it.

 

[Miraculix]

Is that because the distilled H20 is void of solutes? My R.O H20 is rebuilt with minerals... I could see how H20 that is void of solutes and how it could indeed make the yeast cell hypertonic and explode. I'd need to see some papers on it, with citations, not hearsay.

-Do your potato test with rebuilt H20 like many larger brewers use, I use, and have had nothing negative thus far using it.

If you add minerals back to the water, it is no longer distilled or ro water. Then the danger is of course gone. Just pure distilled water is dangerous for yeasts. Most yeast rehydration instructions mention this, if that's enough paper for you.

 

[Jtk78]

Ok, this prompts a question for me. So I have been using RO water for all of my yeast starters using DME as the yeast food source. I have not been adding any minerals to the water for the starters. I've never had a starter fail. My beers usually finish in the 1.010 - 1.015 range depending of course on mash temp, grain bill, etc.

Am I reading I should NOT be using RO water exclusively for my yeast starters? Or, are through minerals in the DME to not cause damage to the yeast.

 

[Miraculix]

If you add dme you add minerals. This is about pure distilled water for yeast rehydration, which is a bad idea, not about yeast starters.

 

[hopjuice_71]

Is that because the distilled H20 is void of solutes? My R.O H20 is rebuilt with minerals... I could see how H20 that is void of solutes and how it could indeed make the yeast cell hypertonic and explode. I'd need to see some papers on it, with citations, not hearsay.

-Do your potato test with rebuilt H20 like many larger brewers use, I use, and have had nothing negative thus far using it.

I don't have good citations for you but I am a professor of biochemistry and microbiology and I can confirm that extremes of hypotonic solutions (RO or distilled water) or hypertonic solutions (e.g. high gravity wort) are not good for yeast (or any other cells for that matter). In fact, depending on our end goal, we routinely use both concepts in the lab to control making cells spill their guts and (usually) die. Yeast are happy in approximately isotonic solutions, which would include water with a reasonable ion content or regular strength wort (starters, "normal" gravity beers, etc). These principles as applied to cell integrity and viability are so long standing and widely applied that I would be hard pressed to find a good citation for you but here is a not so good 50 year old one that deals with yeast protoplasts: https://www.ncbi.nlm.nih.gov/pubmed/5657263.

Personally, I rarely use dry yeast because even my tap water is pretty close to distilled so I can't really benefit from the purported benefits of rehydration. When I do use dry yeast, I just sprinkle it in the wort and get better results than when I have tried to rehydrate.

 

[ClaudiusB]

-Do your potato test with rebuilt H20 like many larger brewers use,

Using your own words "I'd need to see some papers on it, with citations, not hearsay. "
What large breweries?

 

[Jtk78]

If you add dme you add minerals. This is about pure distilled water for yeast rehydration, which is a bad idea, not about yeast starters.

Thank you for the clarification.

 

[Miraculix]

Thank you for the clarification.

No problem!

 

[Bubbles2]

The thread is about R.O H20. Where I was corrected why I was not finding my answer in the 4th post.

@Claudius https://brewingindustryguide.com/ho...ems-are-helping-breweries-overcome-water-woes

IF you all read the O.P instead of this telephone version of a post....Including Distilled, and making starter with DME (which you want to use DME instead of Sugar as to not make the yeast a lazy replicated slacker)

 

[ncbrewer]

Personally, I rarely use dry yeast because even my tap water is pretty close to distilled so I can't really benefit from the purported benefits of rehydration. When I do use dry yeast, I just sprinkle it in the wort and get better results than when I have tried to rehydrate.

Thanks very much for this comment. I've been wondering about my tap water. Our county water is treated by reverse osmoses, and then goes through calcite stabilization filters, which adds back some hardness (45) and alkalinity (55). I'll try dry pitching and see how it works. I'm a little worried about being too cool for rehydration since I pitch at about 64F, but it's worth a try.