Yeast starter

[Otto Von Blotto]

I'm guessing you're referring to oxidation of the starter itself having a negative effect on the main batch? I don't think this is really an issue, as the number of people pitching full starters while active, or even after they've fermented out, is too high for this to be a problem.

 

My reasoning behind crashing and decanting my starters is mainly based around the way I brew; trying to brew smaller size batches to allow for the full starter volume to be pitched would potentially increase risk of infection in my cubes, as they wouldn't be completely full. The same reasoning applies to using some of the actual batch wort for the starter, as well as not being as good for harvesting yeast from my starters.

[Austy]

I'm guessing you're referring to oxidation of the starter itself having a negative effect on the main batch? I don't think this is really an issue' date=' as the number of people pitching full starters while active, or even after they've fermented out, is too high for this to be a problem. [/quote']

 

Yep - this is what I was referring to. I noticed you said you tip off the 'spent' wort and only use the yeast cake in the main batch. I understand why now. For a standard brew technique - it seems like doing that would be a waste of ingredients...?

 

Should I see krausen activity in the flask? So far I haven't seen any apart from a few bubbles here and there.

 

Cheers,

 

Aaron.

[Otto Von Blotto]

It can be a waste depending on how you do it - if you design the recipe to account for the starter volume and the amount of DME used in said starter, then you can pitch the whole thing and the beer should turn out as intended. But if you make the batch up full size and then tip another 2 litres or whatever of unhopped beer into it, it may change it a little, so it may be better to crash and decant in that instance.

 

I guess it's a little different for me as well doing all grain because I don't use malt extract in my recipes anyway, so I have no issue tipping it down the sink. The only reason I buy DME anymore is to make yeast starters.

 

You may or may not see much krausen activity in the flask. US-05 isn't a huge krausen forming yeast anyway; bubbling and condensation on the inside of the flask are good indicators of fermentation. In my case with a stir plate, at first it appears quite dark in colour, but the mixture becomes more opaque and lighter in colour as more yeast is grown. Without a stir plate this effect would be lessened as it's not constantly agitated, but you should be able to notice a difference when you swirl it up by hand.

 

One last thing, you say you mixed it up with 2.5 litres boiled and cooled water, given you've got an Erlenmeyer, next time try mixing it up cold in the flask and boiling the whole thing on the stove, just saves a bit of time and effort sanitising the flask and uses less vessels. (And it looks kinda cool... ) If you have electric hotplates/elements, the flasks can be used on these as well but if you are hesitant, you can put the flask in a pot with water and boil it that way on there.

 

Cheers

 

Kelsey

[Austy]

Thanks Kelsey :-)

 

Yep - I sprayed the flask with Starsan and let it drip to virtually dry. Then filled to 2.5L, boiled on the stove, covered with foil, and left to cool for the day before pitching hydrated yeast.

[Otto Von Blotto]

Thanks Kelsey :-)

 

Yep - I sprayed the flask with Starsan and let it drip to virtually dry. Then filled to 2.5L' date=' boiled on the stove, covered with foil, and left to cool for the day before pitching hydrated yeast.[/quote']

 

No dramas mate

 

Yep sounds pretty much like my procedure aside from the Starsan. Probably not a bad idea to use it but I figure the boiling will take care of that side of things anyway, so far have had no issues.

[pcmax]

I posted some queries on another forum about making a yeast starter with some Lallemand BRY97 yeast because the Mr Malty website had advised that a starter was required after entering my data.

There were almost unanimous replies telling me that starters are only ever required with commercial liquid yeasts and that dehydrated yeast only required rehydrating.

I made a starter anyway just because I wanted to try it out & the beer turned out great. So what's the go with starters and dry yeast if you need to get the cell count up?

[antiphile]

As you can imagine, it is rather difficult to make a general rule that covers every situation. I have no idea how you may have phrased your question on that forum, but I suspect many of those answers may have been pretty relevant to your particular situation at that time.

 

The number of viable healthy yeast cells to pitch depends on many factors including:

1. The type of beer and ferment temp;

2. The strength of the wort;

3. The volume of the wort;

4. The ferment time-temp schedule;

5. The yeast variety and/or strain being used;

6. What features you want out of it (esters/phenols etc);

amongst other factors.

 

To address most of these, you have to know things like:

a. The initial yeast cell count (eg. many but not all liquid yeasts start with about 100 million viable cells; Safale 11.5 gram dried yeasts are usually initially packaged with 200 billion cells; Mangrove Jacks 10 gram dried yeasts are usually initially guaranteed with only 50 billion cells IIRC; all other yeast manufacturers vary their viable count (and I magine by variety too);

b. Time since packaged;

c. How it was stored;

d. How it was harvested;

etc etc.

 

So you can see, in the very best scenario, the number of viable packaged cells will be a rough estimate without doing lab tests on each batch (and there's even a huge variation when doing lab analyses), even before throwing in all the many variables in making a starter.

 

Probably one of the best starting points for estimating how much yeast is needed for a batch is:

In his book, An Analysis of Brewing Techniques, George Fix states that you need to pitch 0.75 million cells per milliliter (per each degree Plato)* for an ale and 1.5 million cells per milliliter for a lager. While these rates are for repitching yeast harvested from fermentation, I have found that they work well for both repitching yeast and when using laboratory cultured yeast that has been subjected to less than optimal conditions since leaving the manufacturer.

 

(* Note: each degree Plato is reasonably close to 4 brewer's points. So a Plato reading of 15 degrees is close to an OG of 1.060; 10 Plato is roughly 1.040 etc.)

 

After that info, your guess is as good as anyone's!

 

[Otto Von Blotto]

I posted some queries on another forum about making a yeast starter with some Lallemand BRY97 yeast because the Mr Malty website had advised that a starter was required after entering my data.

There were almost unanimous replies telling me that starters are only ever required with commercial liquid yeasts and that dehydrated yeast only required rehydrating.

I made a starter anyway just because I wanted to try it out & the beer turned out great. So what's the go with starters and dry yeast if you need to get the cell count up?

 

That sounds pretty familiar. For a "normal" OG (low-mid 1040s) wort of 5 gallons (19 litres), a starter wouldn't be required with dry yeast; rehydrating is a good idea though.

 

However, in my opinion there is nothing wrong with rehydrating a packet of dry yeast and throwing it into a starter to build up the cell count if required. The key here is rehydrating it first, though. When I brewed a few lagers with W34/70 I made a starter from the original packet on the first batch so I didn't have to buy another one for it, and then made starters from the harvested yeast after that. Most of the reason people don't bother is because dry yeast is cheap, not because making starters with it doesn't work.

 

When I did my last pale ale I built a starter from a fresh packet of US-05, not because I needed the cells, but because I harvest yeast from starters rather than the FV trub. This is the main reason I make starters with dry yeast now.

[joules]

I just did my first starter but will be pitching the whole thing.

 

I cannot afford the yeasties so have been yeast washing (PITA!). So yeah a set of yeast strains would be ideal...So would a entire factory floor dedicated to my brewing.

[Otto Von Blotto]

Yes, I found yeast washing a PITA too, that's why I ditched it and now harvest from the starters themselves. I find it a lot easier to simply mix it up and tip some into a jar and fridge it, than all the other crap involved in washing yeast.

[pcmax]

As you can imagine' date=' it is rather difficult to make a general rule that covers every situation. I have no idea how you may have phrased your question on that forum, but I suspect many of those answers may have been pretty relevant to your particular situation at that time.

 

The number of [b']viable healthy[/b] yeast cells to pitch depends on many factors including:

1. The type of beer and ferment temp;

2. The strength of the wort;

3. The volume of the wort;

4. The ferment time-temp schedule;

5. The yeast variety and/or strain being used;

6. What features you want out of it (esters/phenols etc);

amongst other factors.

 

To address most of these, you have to know things like:

a. The initial yeast cell count (eg. many but not all liquid yeasts start with about 100 million viable cells; Safale 11.5 gram dried yeasts are usually initially packaged with 200 billion cells; Mangrove Jacks 10 gram dried yeasts are usually initially guaranteed with only 50 billion cells IIRC; all other yeast manufacturers vary their viable count (and I magine by variety too);

b. Time since packaged;

c. How it was stored;

d. How it was harvested;

etc etc.

 

So you can see, in the very best scenario, the number of viable packaged cells will be a rough estimate without doing lab tests on each batch (and there's even a huge variation when doing lab analyses), even before throwing in all the many variables in making a starter

 

As I mentioned I entered all my details into a pitching rate calculator. (It was the Brewers friend one not Mr Malty) The estimated OG is 1.055 for a 5.5g batch using the "pro Brewer 1.0 high gravity ale" selection for the "target pitch rate, using Fermentis/Safale US-05 yeast which has a cell count (according to the manufacturers website) of >6b cells per gram when packaged so let's be optimistic and assume that we get around 8b cells per gram when it gets to me.

If I add one 11g packet of yeast the calculator tells me that I am under pitching by 195b cells so I figure I need to add two packets (22g) but then still under pitching by 107b cells and still recommends I make a starter.

To be on the safe side I'm using 2 packs of yeast AND making a starter......