Top fermenting yeast identification.

[McMullan]

Just remember scaling things down initially can help reduce the risks.

 

[Bassman2003]

@McMullan - If I could ask one more general yeast question I would value your input:

Right now with my frozen 50ml vials, I see about 7-8 ml of compact slurry in the bottom. I prop this up with 250ml - 2L starter wort routine. With the new 2ml vials I have about 1ml of compact slurry in the bottom. This will be propped up with a 50ml - 200ml - 2L starter wort routine.

My question is about overall number of cells created - beginning numbers vs amount of starter wort used.

Is the final number of created cells more related to the size of the last starter (2L) or the amount of original cells?

With the two regimens above, it would appear that the 50ml vial would result in creating more cells in the end. The 2ml would end up with more vitality but would it have cells numbers that were comparable?

Thanks!

 

[McMullan]

My question is about overall number of cells created - beginning numbers vs amount of starter wort used.

Assuming you are adding enough healthy cells (not "under seeding" and simply doing a mini-fermentation after limited biomass production), cell density is determined primarily by volume of media, all things standardised, e.g., oxygenated wort (1.040) with sufficient nutrients.

With the two regimens above, it would appear that the 50ml vial would result in creating more cells in the end. The 2ml would end up with more vitality but would it have cells numbers that were comparable?

The 2ml is more likely to end up with more healthy yeast cells at the end of the final step-up of the same volume after a comparable series of step-ups. I'd say stick with 5X step-ups (by volume) mostly to minimise the chances of under seeding.

 

[Bassman2003]

Thank you very much for the great information. I am understanding the term "under seeding" as putting too few cells in too much wort. Basically over working the cells and resulting in a less than optimal amount of cell creation. Is this on point?

So then I would be executing a step-up routine of 20ml-100ml-500ml-2.5L for one 2ml vial. I just want to make plenty of cells for a normal 5 gallon batch starting from a single 2ml vial. If I want to do a heavy pressure batch for an IPA like 2 bar, I could do 2 vials in parallel.

I appreciate you input on yeast as it is a vast topic. I want to be clear on my approach so I can make all of the pressure canned starter wort in easy to use sizes.

 

[McMullan]

I am understanding the term "under seeding" as putting too few cells in too much wort.

Yes, exactly. 'Seeding' in terms of cell culture terminology.

 

[Bassman2003]

@McMullan - I am forecasting for my new yeast starter method from 2ml vials and wanted to ask your opinion - Would you have an issue with keeping the 20ml, 100ml & 500ml propagation steps at 1.020 then moving to 1.035/1.040 for the 2.5L step?

This would make the pressure canning a lot easier. I could make a qt mason jar of the 1.020 wort and use it for the first three steps by pouring a bit out and keeping it sealed in the fridge until the next step.

Thanks again for your help. I am seeing a lot of potential with this approach as overbuilding the starter a little and grabbing a few 2ml vials worth of slurry seems like a better approach than harvesting from a batch.

 

[McMullan]

@McMullan - I am forecasting for my new yeast starter method from 2ml vials and wanted to ask your opinion - Would you have an issue with keeping the 20ml, 100ml & 500ml propagation steps at 1.020 then moving to 1.035/1.040 for the 2.5L step?

This would make the pressure canning a lot easier. I could make a qt mason jar of the 1.020 wort and use it for the first three steps by pouring a bit out and keeping it sealed in the fridge until the next step.

Thanks again for your help. I am seeing a lot of potential with this approach as overbuilding the starter a little and grabbing a few 2ml vials worth of slurry seems like a better approach than harvesting from a batch.

The first step is fine at 1.020 and usually the only one I pressure cook. The subsequent steps I have at 1.040 and just double boil then store in the freezer. I use kettle wort and just make a little extra occasionally on brew day. Just simmer it under a lid for 20min after adjusting gravity to 1.040. The lid helps keep it at 1.040. This is effectively sterilised starter wort now. If there were any surviving spores in the kettle wort they’ll ‘germinate’ overnight then get zapped by the second boil the next day. Sometimes it gets left in the fridge for 2-3 days. The trick is to pour it hot into hot, oven sterilised bottles then cap with lids boiled in water at the same time the wort is simmering. Then leave to cool before freezing. I prefer to have each step prepped individually then just pour straight into the next step when ready. Just take it out of the freezer the night or morning before use. Sometimes, for whatever reason, you might want to delay stepping up by storing the just-finished step in the fridge for a few days. It’s just more flexible to have the different steps in separate bottles, I think.

 

[Bassman2003]

Thanks for your input. It is easy to pressure can them all for me but I thought I could limit the amount of small jars by using one larger jar for the first three steps. I will find a way forward. Maybe make the qt. mason jar of 1.040 wort and just dilute with boiled water upon pouring for the first step.

 

[McMullan]

Thanks for your input. It is easy to pressure can them all for me but I thought I could limit the amount of small jars by using one larger jar for the first three steps. I will find a way forward. Maybe make the qt. mason jar of 1.040 wort and just dilute with boiled water upon pouring for the first step.

That should be fine as long as it remains contamination free. It does introduce risks associated with more handling, though. I’m a bit sceptical about pressure cooking something as complex as homemade wort. It’s a different product and likely has reduced nutritional qualities. The first step, like standard lab media, is just to wake up the cells and get them adapted to growing again. Downstream steps, I’m more interested in promoting biomass.

 

[ba-brewer]

I have been pressure canning wort for a few years and have not noticed anything bad happening. I do 1020 1/4pints and 1040 1/2pint, pints and quarts. A little work to clean and canned the jars but quite convenient to just open a jar to step up a starter.

 

[McMullan]

I have been pressure canning wort for a few years and have not noticed anything bad happening. I do 1020 1/4pints and 1040 1/2pint, pints and quarts. A little work to clean and canned the jars but quite convenient to just open a jar to step up a starter.

Same here, but when I started making my own starter wort and double boiling it, which was more convenient due to small volumes, I noticed it seemed better. Researched the literature and it became obvious possibly why. Pressure cooking reduces the free amino acid content by quite a lot. I’m a ‘fresh’ wort convert. Simmered not under pressure. For guaranteed sterility and long-term storage at room temperature, pressure cook. But once we get past the initial step starter, we’re in ‘food’ territory and just need to follow basic food hygiene practices. Promote lots of healthy yeast then let the ethanol do the rest.

 

[Bassman2003]

This are great points. Often convenience, even small gains, comes with tradeoffs.

1) My idea of opening a Qt. sized mason jar is a small risk. I would open, pour swiftly and put the lid right back on with a tight seal in the fridge. Star san spray everything as well. The time in between steps might be 1-4 days, then open again, 1-2 days, then open again, done.

I would ask is this level of risk acceptable?

2) No doubt the 250F temperature & pressure nukes the wort. The color change is the first obvious sign. Is there a way to counteract this? Maybe add some extra nutrient before canning the batch?

When I make the starter wort I do an all grain mash to double+ strength, lauter then fill each mason jar from the lauter tun. I add zinc but could easily add other nutrient. This one day yields 12-18 months of starters that are ready to go. So it is just too convenient. So it would be great to find ways to improve the process.

Thanks

 

[McMullan]

I would ask is this level of risk acceptable?

Only you can answer that, because it’s your decision. For me, it isn’t worth the risk on the first step. After that, it doesn’t bother me.

 

[Bassman2003]

Once again, thanks for your input. Do you have any thoughts on #2? I had not heard about canned wort being deficient. I do not know about free amino acids in wort, but since the majority of it gets discarded, any way to supercharge the raw wort in an effort to fortify the parts will be lost in the process?

 

[McMullan]

Me neither, but if you survey the literature (nutritional quality after pressure cooking) it seems to be a general issue. Free amino acids are very important for yeast metabolism and growth. The primary nitrogen source. One of the key limiting factors generally. Not much synthesis of nucleic acids or protein without it, for example. Pressure cooking potentially halves the free amino acid content. Probably other reduction for other nutrients too. But that's not to say pressure cooked wort doesn't work. Obviously it does work. Just not as well as non-pressure cooked?

 

[Bassman2003]

What about adding something like this product?

FERMAX Yeast Nutrient is a balanced blend of proteins, amino acids and vitamins to improve yeast activity during fermentation. Improves attenuation and speed of fermentation.

Not sure if added amino acids = free amino acids in the canned wort.

 

[McMullan]

A bit like throwing away a glass of beer just to refill your glass, in my mind.

 

[Bassman2003]

Noted If pressure canned wort is damaged, makes me wonder what DME (peoples' old starter favorite) is like compared to all grain wort.

 

[McMullan]

Yes, why I stuck with making my own starter wort. All fortuitous too. Ran out of DME with no LHBS. I had a choice, make some all-grain starter wort or use YPD media, which smells and tastes pretty bad.

 

[Bassman2003]

The first step is fine at 1.020 and usually the only one I pressure cook. The subsequent steps I have at 1.040 and just double boil then store in the freezer. I use kettle wort and just make a little extra occasionally on brew day. Just simmer it under a lid for 20min after adjusting gravity to 1.040. The lid helps keep it at 1.040. This is effectively sterilised starter wort now. If there were any surviving spores in the kettle wort they’ll ‘germinate’ overnight then get zapped by the second boil the next day. Sometimes it gets left in the fridge for 2-3 days. The trick is to pour it hot into hot, oven sterilised bottles then cap with lids boiled in water at the same time the wort is simmering. Then leave to cool before freezing. I prefer to have each step prepped individually then just pour straight into the next step when ready. Just take it out of the freezer the night or morning before use. Sometimes, for whatever reason, you might want to delay stepping up by storing the just-finished step in the fridge for a few days. It’s just more flexible to have the different steps in separate bottles, I think.

I had another read-through of your method and I might be able to pull it off. I would need to boil in my 10 gallon boil kettle, let it sit overnight in that same pot with the lid on, then boil the next day and transfer through the outlet into the hot mash jars. Though this would all take place out in my garage. Is that a non-starter or does the temperature eliminate the risks?

 

[McMullan]

Should be fine. I don't make starter wort on that kind of scale, though. I'll either make a mini mash in the kitchen to get 2-3L or, more often, make a little extra on brew day then store it. Latter being a lot easier, of course. For me, one of the benefits of leaving it overnight is you get pretty trub-free wort after pouring it off into a pan for the second boil. I prefer to limit trub, especially for bottom cropping yeast as I go on to harvest and repitch several times, so I want to max cells rather than trub. It's up to you, though, if you're going to to reboil (simmer) with a load of kettle trub. Don't forget it needs to be transferred hot to hot jars so as not to risk breaking the jars. Some kind of heat-proof gloves that don't limit handling too much are a good idea too.

 

[Bassman2003]

Thanks. I can get trub free wort with my rotating spigot as well as pouring the finished contents through a tea strainer from the mason jar. The hot jars are a drawback though. I will need to heat the jars inside where the oven is then carry them out to be filled. Handling them is dangerous. But they could sit and cool right there.

Is it worth it for the free amino acids?

BTW, are you able to reuse the mason jar lids since this is not really a pressure canning situation? I like how the jars and lids will be clean in comparison to when the high temp boil takes place in them.

 

[McMullan]

Is it worth it for the free amino acids?

I think so.

BTW, are you able to reuse the mason jar lids since this is not really a pressure canning situation?

I use lab bottles regardless. Been reusing them for years.

 

[Bassman2003]

I use lab bottles regardless. Been reusing them for years.

Makes sense as freezing the glass mason jars is a little dicey as well. Can you point me to the lab bottles? What material are they? I was picturing glass since you put them in the oven but I guess certain plastics would be fine at low oven temps. 250F 300F?

 

[McMullan]

Standard borosilicate glass. Just don't fill the mason jars much more than about half.

https://www.homebrewtalk.com/threads/stir-shake-harvest.695792/#post-9175423

 

[Bassman2003]

Thanks! I see. Great summation on the other thread as well. I have some thinking to do...

 

[Bassman2003]

McMullan,

I wanted to revive this thread to get your opinion on a different approach for canning wort. The whole reason for pressure canning is to avoid the risk of Botulism. Canning guidelines say pH 4.6 is the divider between needing to pressure can or just boil. What if one lowered the pH of the starter wort to 4.6 and just boil-canned? So basically brewing a batch of beer without chilling it and storing in mason jars?

Would the yeast performance/activity be affected using pH 4.6 wort for the entire starter?

What is the better of the two choices - decreased performance with pressure canned wort or no-pressure pH 4.6 wort?

One could mix in higher pH wort or add alkalinity if 4.6 is too low for good yeast growth.

Thanks for your input.

 

[doug293cz]

McMullan,

I wanted to revive this thread to get your opinion on a different approach for canning wort. The whole reason for pressure canning is to avoid the risk of Botulism. Canning guidelines say pH 4.6 is the divider between needing to pressure can or just boil. What if one lowered the pH of the starter wort to 4.6 and just boil-canned? So basically brewing a batch of beer without chilling it and storing in mason jars?

Would the yeast performance/activity be affected using pH 4.6 wort for the entire starter?

What is the better of the two choices - decreased performance with pressure canned wort or no-pressure pH 4.6 wort?

One could mix in higher pH wort or add alkalinity if 4.6 is too low for good yeast growth.

Thanks for your input.

@Bassman2003 : McMullan won't be answering anytime soon.

@Everyone: The reasons for this are not a suitable topic for discussion, so please don't.

doug293cz
HBT Moderator

 

[robint]

@dyqik fabulous vid thanx10^6

Video is located here, in post #78.