# Yeast in a bag



## Glomp (19/7/17)

Wyeast and Whitelabs do it so I instead of traditional yeast rinsing I used a snaplock bag instead of bottles.

I tried to separate the yeast using this technique but the flow was a bit hard to control. It worked but would need some refinement.

https://aussiehomebrewer.com/threads/poor-mans-yeast-separation-system.95526/





I then syphoned the crap out. 






Then started sealing the bag and split into smaller bags












and divided again





Sorry about the focus. That is crap but the technique has a minimal of exposure to the nastys


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## Stouter (19/7/17)

That's great. I was worried when I saw the single seal zip lock at the start, but the plastic sealer machine would sort any sealing issues. And the syphon idea leaves everything undisturbed.
Nice work.


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## technobabble66 (19/7/17)

Great idea & thanks for demonstrating it. 
How we'll have you tested this?
IE: how long have you kept them (& still had them fire up)? Have you had any infections?

Or is this your first venture into this technique?


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## DJ_L3ThAL (20/7/17)

Isn't the white labs plastic a special 'one way' permeability design so as to let out CO2 pressure but not let in any O2? Not sure if sandwich bags would have that property or not?

Either way great thinking and nice work. Hopefully hear back your results soon [emoji106]


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## MHB (20/7/17)

I would use a barrier bag, stops O2 getting in which would increase the storage time.
The type of bags used for vacuum packaging are excellent, as for one way permeable I cant help there, its a nice idea if you could find them.
Get the yeast cold and into the dark as quick as you can and you should get the best results.
Mark


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## Lyrebird_Cycles (20/7/17)

No such thing as one way permeability. Many films have differential permeability, which gas is favoured depends on the solubility of the gas in the polymer.

As an example plain polythene (your sandwich bag) has low permeability to water vapour but high permeability to oxygen because oxygen is quite soluble in long chain alkanes where water vapour isn't (they are hydrophobic).

The bags made for vacuum sealers are generally PE with extra layers to improve strength and reduce gas permeability. A typical extra layer would be PVDC, used because it has very low permeability to oxygen and nitrogen. Its permeability to CO2 is about 5 times higher than O2 so it qualifies as differentially permeable.


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## Glomp (20/7/17)

Thanks for the ideas.

This was the techniques maiden voyage so I can't yet tell the final result.

I did find the snaplock plastic too thin and will use a large vacuum bag next. Split it and then vacuum pack in foil carrier bags. Back to ebay I shall go.

I have bought a microscope and a couple of counting chambers slides so will be able to get some idea about viability.

There are some real positives if it works as it is so easy with the only real preparation chucking some water in a pressure cooker and leaving it to cool overnight or is it better to not worry about rinsing and just remove the beer supernatant from the bag. That would make it even easier and remove another source of contamination.

The other thing I thought of is that I could easily heat seal a corner of the bag when needing to do a cell count so I could get a sample without contaminating the rest of the yeast.


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## Glomp (21/7/17)

I am officially insane.

I am going to get a roll of 15cm wide vacuum sealing bags and will try to ferment in the bag. All i will need is a blow off tube and should be good to go.

The maximum height will be around 2m.

I am also thinking of chucking a brewometer in the bag to measure what is happening.

This should be quite fun. Lucky i no longer have a swmbo otherwise this would not happen in the kitchen. 

Whitelabs does it so i know it is possible

Cheers Glomp


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## Glomp (27/7/17)

I have ordered the foil vacuum bags but in the meantime I have tried with the normal plastic vacuum bags. Pretty much the same technique but this time using a bag sealer where the snap lock closure was before.

This picture shows the syphon before use.









After the syphoning the yeast is massaged to spread evenly throughout the bag.








Then the bag is split into whitelab bag sizes.






Then the bag is segmented using a heat sealer




And then cut into individual packets.







Next time I would make the initial large bag longer as there was not much leeway in doing the bag seals. But overall pretty quick and easy


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## MartinOC (31/7/17)

Mate, that's some really innovative lateral thinking & I like it a LOT.

Couplea points for consideration:

1. What do you anticipate the shelf-life of one of your "sachets"?

2. If those beasties continue with their life-cycle & have enough residual food, it's probable that they'll produce enough CO2 to burst the sachets in storage.

3. Have you considered adding glycerine to the mix prior to packaging in order to be able to freeze them for long-term storage in a freezer?

$0.02


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## Grott (31/7/17)

You gave me this idea as I bulk buy a fair bit. Bought one of those sealing units, 400mm wide. Excellent. When freezing a lot of something (sausages, steaks or whatever) place in the vacuum seal spaced out at serving intervals. Vacuum seal and then seal with the sealer unit between these serves. Only one vacuuming required and cut off serves as needed, no re-vacuuming.


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## Tony121 (31/7/17)

You may have an issue keeping the sections between the meat flat when vacuuming to enable you to seal properly. Then again, a little care and it should be fine.


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## Glomp (1/8/17)

Hi All,

Nice work Grott.

MartinOC in answer to your questions.

1. What do you anticipate the shelf-life of one of your "sachets"?

I typically get around 4 months after spinning up a commercial product and putting it into 50ml vials. After that the yeast starts looking a bit dodgy. I would be happy if I get 2 months with this method as I really plan to use only about 4 or 5 yeasts. I have a microscope and will be able to get a better idea about longevity. I am just waiting on getting some foil vacuum bags and then will do some counts. 

So from the original pack I will split into 3 parts.

Then give them a spin and then use the YIAB method as its just so easy. That's the intention if it works.

2. If those beasties continue with their life-cycle & have enough residual food, it's probable that they'll produce enough CO2 to burst the sachets in storage.

I didn't have any bursting troubles with the first trial but did on the second. 

Probably due to a few reasons but these ones are pretty obvious.

a) Poor sealing technique.. I had the sealer set on the mid way point. The first seal done was perfect with subsequent seals getting worse and worse and almost cutting and not sealing as the unit got hotter and hotter.
After seeing this it was a simple solution to put the sealer on the lowest setting as the vacuum bags don't need much heat to seal.

b) Probably the biggest fault was that I had too much yeast in each bag. There was somewhere between 2 to 3 times more yeast in each bag than the whitelabs sachet. Next time I will use a lot longer bag and try to have about 50g in each bag.

c) The syphon tube kept bending at the bottom so I couldn't get as much supernatant out of the bag as I wished to. It will be pretty simple to change the syphon tube to a rod.

d) The first trial I rinsed with sterile water and the bags didn't bloat much. The second one was not rinsed.

3. Have you considered adding glycerine to the mix prior to packaging in order to be able to freeze them for long-term storage in a freezer?

I haven't simply because I don't have any freezer space. I live in a townhouse and have 1 kegerator, 1 normal fridge and 3 chest freezers for fermenting and conditioning in my kitchen. If I added another freezer I would be forced to sleep standing up.


I will be having another go at YIAB tomorrow to see where I can make improvements. It may be a total failure but its worth a crack.

Cheers Glomp


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