Instant reaction in secondary?

[poges]

Hi

Had a wheat beer (brewieser kit with wheat yeast and 500g wheat malt) which I racked from primary to secondary on Sun (2 days ago). Twas bubbling through the airlock in the primary. Had been in there 5 days.

After racking airlock activity dropped to zero. Was worried about how much CO2 would be sitting above the beer so opened secondary up and sprinkled in a couple of teaspoons of dried malt (hoping to get some CO2 produced). Had an instant (as in within five seconds) reaction and about half an inch of krausen / foam rose up over the entire surface of the wort.

Any ideas what happened?

[bottle top]

Something to do with an increased number of nucleation sites causing CO2 to rapidly come out of solution springs to mind, but you'll have to google (or wait) for a better explanation.

You get the same effect adding any kind of powder to a carbonated beverage.

[Chris]

You really didn't need to add extra malt. The reason your beer stopped bubbling was probably due to the release of much of the CO2 during racking. It may well have started bubbling again if you'd given it a day or so. Enough to get a layer of CO2 on your beer anyway.

[KEG]

i agree with bottle top's explanation.

[rwh]

Yep. Increased nucleation sites is the answer. You'll get the same effect if you sprinkle sugar into lemonade or any other carbonated beverage.

As for adding fermentables after racking, I always add a tablespoon of dextrose to mine, but I boil it first in a little water, and add this (uncooled) liquid to the beer in secondary. This serves two purposes: killing any nasties and dissolving the granules to avoid the bubbling effect.

[Kevnlis]

As for adding fermentables after racking, I always add a tablespoon of dextrose to mine, but I boil it first in a little water, and add this (uncooled) liquid to the beer in secondary. This serves two purposes: killing any nasties and dissolving the granules to avoid the bubbling effect.

Same...

[scanman]

You learn something new every day on this forum!

[Chris]

Out of curiosity, why do you need to add the extra sugars?

[Kevnlis]

I do it for two reasons. To get some of the yeast back to the attenuative phase again (to be sure they have finished with the simple sugars), and to quickly get CO2 into the headspace.

[Chris]

But surely there is a lot of CO2 being released that was previously trapped in the beer. I can't see that a tablespoon of sugar will add even 10% to what is already being released from the beer already.

And as far as the yeast goes, being back in suspension is usually more than enough to get them chewing through any remaining maltose isn't it? I've never really had any issue with getting a beer at least a few points below what beersmith or equivalent suggests as FG.

I just don't really see the reason. That is especially the case if you rack the beer when it still has a point or two to drop anyway.

Does anyone have any literature on this particular point?