No Krausen

[Georgedgerton]

Hi fellow brewers. I am in the process of making a 1 litre WLp925 yeast starter. The airlock has been bubbling away for a couple of days and there is certainly plenty of activity going on, however there is absolutely no trace of any krausen formation. The yeast wasnt transported in the most ideal of environments, but obviously its still viable enough to be fermenting the wort. The only other thing I did was use a different saniterer in the flask than what I normally use. The sanitiser was Star San, and it left a lot of foam in the flask, and I wondered if this had any effect on it. Any ideas on this?

 

[razz]

Iv'e experienced that before GE. Put a starter on and go to bed and the next day the solution has noticeably thickened and and there is hardly a spec of krausen on the glass, yeast dependant maybe. How fast do you spin the starter?

 

[philrob]

Mostly my starters do not display kraeusen. Nothing to worry about.

 

[Georgedgerton]

Iv'e experienced that before GE. Put a starter on and go to bed and the next day the solution has noticeably thickened and and there is hardly a spec of krausen on the glass, yeast dependant maybe. How fast do you spin the starter?

Good old ongoing "swirl by hand" - must invest in a magnetic stirrer

 

[kadmium]

Yep a properly stirred starter is leaps ahead of hand swirled but its still better than nothing!

Most of my starters have foam, but not what you would call a krausen. Looks more like head on a beer as opposed to yeasty krausen. Any bubbles or foaming at all?

 

[razz]

Good old ongoing "swirl by hand" - must invest in a magnetic stirrer

I see. Getting a stirrer is pretty good value for money and the starter will be ready sooner. They don't have to spin fast, just enough to keep the yeasties moving around. Getting back to your current starter, generally you will know it's finished if the yeast and beer separate.

 

[mje1980]

Good old ongoing "swirl by hand" - must invest in a magnetic stirrer

I often don’t use my stir plate anymore, the swirl by hand works for me just fine. For ales under 5% which is mostly what I brew, I find no difference in yeast performance. Over 5% I usually make a midstrength beer and pitch on 1/3 of the cake. Last few sub 5% lagers I’ve just swirled by hand and they turned out fine.

 

[kadmium]

I guess the ease of using a stirplate vs swirling is a bonus for stirplates, along with increased cell counts, and a more reliable prediction on cell counts if using a stir plate.

Non stirred starters rarely have a growth factor of more than 2.5ish and very rarely above 3.

Stirred starters have growth rates much higher, and have a growth rate of up to 2B cells per gram of extract while non stirred shaken have a rate of 0.6B cells.

While this may be adequate, bear in mind there is almost no reason to do a small (sub 3L) non stirred starter. You might as well just pitch a second packet.

Considering DME is around $1 for 100g you're spending $1 to grow an additional 60B yeast, while simply stirring it will get you closer to 140B or 2.5 times as effective.

A simple illustration is a packet of yeast with a manufacture date of 6 weeks.

Viability 72%

Starter size 2.5L

Inoculation 28.8 million / ml

Stirred: 353B new cells total 425B
Shaken: 156B new cells total 228B

A good pitch rate for a Lager is 1.5m/ml per plato. For a 1.045 lager you need 336B cells so by simply stirring a 2.5L starter you can actually harvest 500ml and still pitch the required number.

Simply shaking you are pitching 100B less than ideal.

Yes, lots of people make good beer without starters and simply pitch 1 packet of liquid yeast. But in my opinion, having a stirrer is a cheap insurance policy. I make wort, yeast makes beer.

Its easy in my own opinion to simply pop the flask on a stirrer and forget about it for 2 days.

 

[Georgedgerton]

I guess the ease of using a stirplate vs swirling is a bonus for stirplates, along with increased cell counts, and a more reliable prediction on cell counts if using a stir plate.

Non stirred starters rarely have a growth factor of more than 2.5ish and very rarely above 3.

Stirred starters have growth rates much higher, and have a growth rate of up to 2B cells per gram of extract while non stirred shaken have a rate of 0.6B cells.

While this may be adequate, bear in mind there is almost no reason to do a small (sub 3L) non stirred starter. You might as well just pitch a second packet.

Considering DME is around $1 for 100g you're spending $1 to grow an additional 60B yeast, while simply stirring it will get you closer to 140B or 2.5 times as effective.

A simple illustration is a packet of yeast with a manufacture date of 6 weeks.

Viability 72%

Starter size 2.5L

Inoculation 28.8 million / ml

Stirred: 353B new cells total 425B
Shaken: 156B new cells total 228B

A good pitch rate for a Lager is 1.5m/ml per plato. For a 1.045 lager you need 336B cells so by simply stirring a 2.5L starter you can actually harvest 500ml and still pitch the required number.

Simply shaking you are pitching 100B less than ideal.

Yes, lots of people make good beer without starters and simply pitch 1 packet of liquid yeast. But in my opinion, having a stirrer is a cheap insurance policy. I make wort, yeast makes beer.

Its easy in my own opinion to simply pop the flask on a stirrer and forget about it for 2 days.

Been brewing for a long time, but also out of it for a long time. Getting back up to speed with a bit of help from folk such as yourself.

 

[kadmium]

Always happy to help, I learn heaps here too! I love the sharing of knowledge!

 

[raturay]

My limited experience with starters on a stir plate is that there is very little visual evidence of fermentation. Makes sense as continual stirring puts it all back in, so it’s happening, just not seen in the form of a krausen.

 

[Killer Brew]

I see little krausen activity on my starters too. As for Star San ..... don't fear the foam.

 

[Georgedgerton]

Thanks to all who contributed to this. It seems to be pretty much the norm rather than the exception.