# Yeast bought in snaplock bags



## brewermp (25/1/15)

Hi all,

When I first started brewing around 4-5 months ago I bought a small amount of yeast from my LHBS store it was titled wb06. It was provided in a small snaplock bag and stored in the fridge. I have two questions 

1. Would it still be good?
2. Would rehydrating give me a better understanding if it was still viable?

Thanks in advance


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## QldKev (25/1/15)

If it was put in a snaplock bag I would not use it, even after a day or so. I would never pay for it stored that way.


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## brewermp (25/1/15)

Yeah I bought it in snap lock bags, never opened though. Looking back I see how stupid the decisions was of purchasing in snap lock instead of vacuum sealed bags. Hind sight is beautiful ey haha


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## Ducatiboy stu (25/1/15)

Rehydrate it. I would bet that its OK


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## brewermp (25/1/15)

Yeah I'm gonna give it a crack.. I've no chilled so am safe to get another packet of something else if need be. I will post photos here.


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## QldKev (25/1/15)

I would not be worried if it will fire up, I'd bet it will. I'm more worried about what other funkies are in for the ride. Those bags are not impervious to air.


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## Ducatiboy stu (25/1/15)

Help, help...the sky is falling.....


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## QldKev (25/1/15)

Ducatiboy stu said:


> Help, help...the sky is falling.....


Gee, that's a useful comment. 

Maybe you should let the yeast companies know they are wasting their money nitrogen flushing and using their foil bags, when they could just pour the yeast into a ziplock bag.

I'm not guaranteeing the yeast will have an infection, I just would not risk it.


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## Ducatiboy stu (25/1/15)

Best be using irradiated sterile water with the yeast then


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## elcarter (25/1/15)

Slow day so I was curios if a microbe can get though a zip lock bag to spoil / mutate yeast. Given it was packaged in a sterile environment, not punctured ect. 

What are zip loc bags made of?

LDPE

http://en.wikipedia.org/wiki/Polyethylene 

Low-density polyethylene (LDPE)[SIZE=small][edit][/SIZE]
LDPE is defined by a density range of 0.910–0.940 g/cm3. LDPE has a high degree of short and long chain branching, which means that the chains do not pack into thecrystal structure as well. It has, therefore, less strong intermolecular forces as the instantaneous-dipole induced-dipole attraction is less. This results in a lower tensile strength and increased ductility. LDPE is created by free radical polymerization. The high degree of branching with long chains gives molten LDPE unique and desirable flow properties. LDPE is used for both rigid containers and plastic film applications such as plastic bags and film wrap. In 2009 the global LDPE market had a volume of about US$22.2 billion (€15.9 billion).[7]

What's the permeation size of LDPE polyethylene?

http://www.goodfellow.com/E/Polyethylene-Low-Density.html

Property Value
Permeability to Carbon Dioxide @25C x10-13 cm3. cm cm-2 s-1 Pa-1 10 
Permeability to Hydrogen @25C x10-13 cm3. cm cm-2 s-1 Pa-1 8 
Permeability to Nitrogen @25C x10-13 cm3. cm cm-2 s-1 Pa-1 0.7 
Permeability to Oxygen @25C x10-13 cm3. cm cm-2 s-1 Pa-1 2 
Permeability to Water @25C x10-13 cm3. cm cm-2 s-1 Pa-1 70 
Permeability to Water @38C x10-13 cm3. cm cm-2 s-1 Pa-1 120

https://www.youtube.com/watch?v=wO1yq6YTJDI

Whats the desity of LDPE and is yeast bigger or smaller?

Density of LDPE 0.92 g/cm3

Density of dry celled walls of Saccharomyces cerevisiae 1.180 g/cm3

From this quick search of un verified or checked internet warrior knowledge ( no idea on half the stuff I just read). I've come to the (no doubt incorrect) conclusion Zip lock bags do let compounds though that may effect your yeast health. 

However they may not let other forms of Saccharomyces though? 

I'm not sure (but suspect) there's other (microbes / pathogens / yeast killing / mutating, compounds) that may be smaller but I think it's time for you all to find some holes in this shit I've just written and put the zip loc bag yeast thing to rest


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## jyo (25/1/15)

Chances are, it'd be useable. Many of us have stored yeast in non-sterile environments like PET bottles without perceivable infections.

But, probably better to use it for a pizza base.


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## Camo6 (25/1/15)

I'd hate to waste a batch of beer that takes me four weeks to produce because of a $5 bag of unknown yeast. But that's just me.
You could always grow it in a starter, decant a bit and taste, but hardly worth the effort.
I wouldn't be so much worried about the integrity of the bag but how it was handled before going in to it.


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## manticle (25/1/15)

Ducatiboy stu said:


> Best be using irradiated sterile water with the yeast then


Boiling water is an easy, safe bet.
Use toilet water if it suits you - no system is perfect but don't shit on others for whatever precautions they want to use.
It's evident from some of your yeast threads that yeast handling is not something you value highly. Fair enough if it works for you.
I have 3 kegs of shit beer I connect with careless top cropping from recent attempts to use up ingredients and that 15 hours of brewing + ferment time and ingredients cost is all now wasted.
I'm returning to my anal wanker ways so I can drink beer rather than tip beer.


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## DJ_L3ThAL (25/1/15)

I must be an anal wanker too...


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## Black Devil Dog (25/1/15)

I've got 2 fermenters full of beer that taste like someone has shat in them. I skimped on the yeast handling/preparation and now I regret it.


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## Ducatiboy stu (25/1/15)

manticle said:


> Boiling water is an easy, safe bet.


Not according to some.


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## elcarter (25/1/15)

Geeze I researched all that science "stuff" and your still intent on ear bashing each other. 

I think we have two polarized views on suitability of yeast packaging material. Best bet to aim somewhere in the middle.

I'm not sure that's with zip lock bags but PET bottles have been used with good results. Just make sure it's been developed with MXD6 catalyst.  ( just being a dick now)

I can see people now walking around with 600ml 'coopers' plastic PET bottles of dry yeast. Should develop a flat bottom for the stir bar. Shake and bake starters..... I'm so on to something here.



> Since beer is especial sensitive to oxygen and has to be protected against loss of CO2, 5% or 8% wt. MXD6 with catalyst should be used for beer


http://www.ilsi.org/Europe/Documents/131.pdf


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## Ducatiboy stu (25/1/15)

manticle said:


> Boiling water is an easy, safe bet.
> Use toilet water if it suits you - no system is perfect but don't shit on others for whatever precautions they want to use.
> It's evident from some of your yeast threads that yeast handling is not something you value highly. Fair enough if it works for you.
> I have 3 kegs of shit beer I connect with careless top cropping from recent attempts to use up ingredients and that 15 hours of brewing + ferment time and ingredients cost is all now wasted.
> I'm returning to my anal wanker ways so I can drink beer rather than tip beer.


Topp cropping is always has more chances of infection than a dried yeast....I am supprised you dont already know this


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## DU99 (25/1/15)

:icon_offtopic: My question is people can buy bulk packets of yeast.how does one open the packet and store it.


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## Ducatiboy stu (25/1/15)

DU99 said:


> :icon_offtopic: My question is people can buy bulk packets of yeast.how does one open the packet and store it.


I put mine into a clean glass jar....or god forbid...a ziplock bag.... :super:


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## brewermp (25/1/15)

So after all of this I have decided to wait. I have stored hops in zip lock bag and it has lost its aroma quick. I think the yeast may go alright but I don't want to spoil this beer over a chance for yeast. I'm still going to rehydrate for shits and giggles though.


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## brewermp (25/1/15)




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## Ducatiboy stu (25/1/15)

brewermp said:


> So after all of this I have decided to wait. I have stored hops in zip lock bag and it has lost its aroma quick. I think the yeast may go alright but I don't want to spoil this beer over a chance for yeast. I'm still going to rehydrate for shits and giggles though.


Storing Hops is a lot different to yeast.

The reason they dry yeast is to make it more robust and easier for storage and transportation and to extend its shelf life.. You can store Hops in ziplock bags, but agreed they dont last as long, but will do OK if placed in the freezer straight after re-packaging them


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## Bribie G (25/1/15)

Vacuum sealer on at Aldi again on Wednesday. Seventy bux.


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## manticle (25/1/15)

Ducatiboy stu said:


> Topp cropping is always has more chances of infection than a dried yeast....I am supprised you dont already know this


You missed my point stu.


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## Ducatiboy stu (25/1/15)

manticle said:


> You missed my point stu.


Did I...?


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## Midnight Brew (25/1/15)

jyo said:


> But, probably better to use it for a pizza base.


Genius! Fantastic idea!


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## TheWiggman (25/1/15)

Stu be trollin', they hatin'.


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## alfadog (25/1/15)

brewermp said:


> ImageUploadedByAussie Home Brewer1422160369.357712.jpg


I had a guy try to sell me a bag of "gravy powder" that looked very similar.... though he wanted more than $5


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## Roosterboy (25/1/15)

I wouldn't use that brew shop again as it's a sign of their lack of knowledge and general slackness.


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## Ducatiboy stu (25/1/15)

TheWiggman said:


> Stu be trollin', they hatin'.


Just puttin a bit a good ole balance back in there


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## brewermp (25/1/15)




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## brewermp (25/1/15)

Roosterboy said:


> I wouldn't use that brew shop again as it's a sign of their lack of knowledge and general slackness.


I haven't since.


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## Yob (25/1/15)

This is a little OT but.. On the odd occasions I use a dry yeast these days, I put a stir bar in the pyrex jug with them and after the 15 minutes rehydration, they go onto the stirplate very gently for half hour... Probably just me but the instructions do say to stir gently for half hour..

Sorry for the off topic, your picture reminded me.


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## Mr. No-Tip (25/1/15)

Ducatiboy stu said:


> Help, help...the sky is falling.....


Far be it for me to agree with AHB's trolliest troll, but he does have a point.

My LHBS has for many years bought bulk yeast and repackaged into ziplock. I've never really liked it, but it was what I had access to and I used it plenty with great success in my early days. I am pretty sure the repackaging was a factor when I tried to stretch US05 on a DIPA and it failed. The yeast did it's job, but it wasn't as ready to go 'over and above' it's attenuation viability. Lesson learnt. Still, tomorrow I am brewing a SIPA with some ziplocked US05 from a mate who bought 500g. I will pitch more than I would normally do, but I will still use it.

Would I use it for a comp? Hell no, but would I trust that the yeast is all good? Yes.

Would I be worried there was enough of a wild yeast in the zip back to cause problems? No. Maybe slightly in the back of my head, but only in the same way as I worry that some wild yeast might drop in the crack of the fermenter as I fill, or that I didn't clean the tap well enough, or some other super unlikely scenario.

The dried yeast will be fine.


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## Ducatiboy stu (25/1/15)

You made a good point


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## indica86 (25/1/15)

Store dry yeast in the freezer. It's the go.
Works for bread yeast.


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## TheWiggman (25/1/15)

I don't know the answer and won't pretend to because yeast is not one of my strong points. My thought process would be "if I think there is a problem with the way this yeast is handled, what is it about the handling that will affect yeast health?"

Temp is one of them. Oxygen? Moisture?

If anyone knows I think this would give a more straightforward answer. elcarter covered Saccharomyces cerevisiae well but surely there's other stuff out there. Otherwise maybe it's not all bad. Maybe.


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## Ducatiboy stu (25/1/15)

Maybe brewers need to think about why and the reasons behind it for producing dried yeast. 

Yeast is a lot more robust than brewers give it credit for.


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## Yob (25/1/15)

so are contaminants.. the yeast's survival is not the issue for me, the handling and exposure is.


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## Ducatiboy stu (25/1/15)

Yob said:


> so are contaminants.. the yeast's survival is not the issue for me, the handling and exposure is.


This is true.

The way you handle dry yeast v wet yeast are very different.

Very different products


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## Yob (25/1/15)

Ducatiboy stu said:


> This is true.
> 
> The way you handle dry yeast v wet yeast are very different.
> 
> Very different products


the practices I employed when I was using/use dry yeast hold me in good stead for doing the same with dry.

I'll be in a position to have my beers tested for bacterial counts and other stuff, so I'm keen to know if _what I consider_ good practice and a "clean" environment is all I think it is :lol: and to be honest, the RIS Im trying to get finished has both, started on Dry Yeast will has had at least one addition of a 'liquid'.. one of my frozen yeasts stepped up... as well. Thats the one I really want tested.. of course, in that I dont have one that came from a zip lock bag yeast to compare.. just sayin..



brewermp said:


> ImageUploadedByAussie Home Brewer1422174448.811443.jpg
> 
> 
> 
> ImageUploadedByAussie Home Brewer1422174473.812089.jpg


mate, Im spewing this didnt come up earlier, I could have got it tested and either confirmed or put to bed, Ive got a friend spending a few weeks in the a well known.. very well known.. Breweries Lab and let me know to have some samples for her. Im seeing her Tuesday.


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## brewermp (25/1/15)

Yob said:


> mate, Im spewing this didnt come up earlier, I could have got it tested and either confirmed or put to bed, Ive got a friend spending a few weeks in the a well known.. very well known.. Breweries Lab and let me know to have some samples for her. Im seeing her Tuesday.


I can always buy some and mail it too you


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## elcarter (26/1/15)

I'll happily open a packet of us-05 and s-04 and zip lock bag it up for testing.


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## Yob (26/1/15)

brewermp said:


> I can always buy some and mail it too you


by Tuesday?



elcarter said:


> I'll happily open a packet of us-05 and s-04 and zip lock bag it up for testing.


Not exactly what Im saying, I could "open a pack" but aint the same thing as a pack in a zip lock for "x" time.. Im in the "**** that" camp but I also have a lot of interest in data currently.. having that (as discussed) sample to test would be astonishingly interesting to me... to get lab results would surprise quite a lot of people I suspect.. either in the "she'll be right mate" crowd (a decent part of me lives there) and the hermetically sealed holding their breath brigade (also a member)

one way or the other, this practice should have data behind it. I have a one off opportunity to get stuff tested, I wish this was part of it.. Im just as interested in a lab tested result as the rest..


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## mje1980 (26/1/15)

Someone should blow yeast sanitisation up


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## AndrewQLD (26/1/15)

The fact that this was obviously a bulk bag of yeast split down into small unsterilised zip lock bags in who knows what kind of premises with the possibility of grain dust from the grain mill next to the packing bench drifting around in the air and possibly using the spoon they used for lunch a little earlier is enough to put me off buying their yeast.
And yes, it could also have been packed in a super sterile room using the latest extraction fan air filtering system, but somehow I don't think so given they are using unsanitised zippy bags


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## Mardoo (26/1/15)

Yob said:


> and the hermetically sealed holding their breath brigade (also a member).


That you Yob? No wait, you don't wear glasses.


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## elcarter (26/1/15)

Can't get it there by Tuesday nor has it been in zip lock bags for x time to make it worth your while.

I don't do the zip lock bag yeast thing. 

One thing you could do is a liquid yeast past it's use by date. I brew with all the out of date yeast I don't sell. Well past the date when the calculators say 0 viability and it still comes good.

We all know from the activity and the ferment it works but how many cells really are left. It would be a small test and far to many variables eg storage temp, time, and strain but actual data may shed light into if were bringing it back from the edge of colony death or was there always a large cell count just waiting?


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