Us 56

[mashdog]

Say that again, used it a few times, the beers gave me serious headaches the morning after.

UPDATE: OK. So i went and bought some amylase. I then had a chat to a brewer at work and he said that i should rack the brew before experimenting with introducing enzymes. a. Just to see what happens, and b. the amylase would leave my APA with little to no body.

So i racked the brew last night and took a hydro reading just after. Still at 1.024. I put the lid on the racking fermenter, filled the airlock and walked away. Came back half an hour later to find the water in the airlock had been pushed a bit. <_< I thought it must just be some thermal expansion/contraction or something.

Not so, it definately seems to be fermenting again (albeit slowly) as i have been getting a 'blurple' from the airlock every half hour or so since. I'll take another reading in a couple of days and see what has happened.

 

[mashdog]

Righto. Well after about a day of slow bubbling after the rack, the SG dropped to 1020. Hasn't moved for the last few days. Still not sure why the rack started things off again. Oxygen????

A 3.5% beer doesn't excite me much so i think i'm gonna try the amylase and see what happens. Gotta have something to drink for xmas!

 

[Fents]

sometimes racking (up) can get the yeast moving again and re awaken them for a second ferment.

 

[mashdog]

sometimes racking (up) can get the yeast moving again and re awaken them for a second ferment.

Thanks Fents. But why? What does the rack do that "re awakens" the yeast?

 

[RobW]

It's called dropping and it resuspends the yeast which can kick off a bit more activity.
Rousing, which is just resuspending in the primery by stirring or rocking, can have a similiar effect.
You need to avoid oxygenation though.

 

[mashdog]

It's called dropping and it resuspends the yeast which can kick off a bit more activity.
Rousing, which is just resuspending in the primery by stirring or rocking, can have a similiar effect.
You need to avoid oxygenation though.

Nice. Cheers for that RobW.

Well i threw in some amylase this morning so we'll see what that does. Should be an interesting experiment. Unfortunately my APA will probably be more of an American Dry.

 

[mashdog]

Well. The Amylase has been in for a couple of days now and nothing has happened! The SG is still at 1020. Gonna just keg and gas it tonight to see how it tastes when cold and bubbly.

Thanks everyone for their help.

 

[Sammus]

could try giving it a swirl to rouse the yeast... probably woulda been a better idea to do that while it was in primary though, with a well purged headspace. I always do this in the last few days of my fermentations to help it get down a few more points.

 

[mashdog]

Thought i'd just finish up the topic... the beer tasted crappy and i tipped it out.

I have done another two since (same recipe using same yeast) but aerated the shit out of the wort after the chiller as it went into the fermenter. I didn't do this previously. These two subsequent brews have fermeneted down nicely (down to about 1010 after 4 days or so).

So as far as i'm concerned... aeration was the issue. I.e. because you are boiling the hell out of your total wort volume in all-grain (i.e. depleting it of oxygen), you must remember to put it back in after cooling. This is not really an issue with partial mashing because the oxygen depleted wort only makes up about half your fermenting volume, the rest you make up with cold, oxygenated water.

 

[Wrenny]

Thanks for your follow up post, mash.

Another good tip to keep in the back of my mind.

 

[mfdes]

Hi Mashdog,

When you brew with extract or partial mash you should be using cool BOILED water, which has also had the oxygen driven out of it and doesn't easily take it back. I can tell you, and I'm sure I'm not the only one, that one of my main problems with off flavours and poor stability was using cold tap water to top up my brews. It comes with its own flora, even if chlorinated.

MFS.

 

[braufrau]

So as far as i'm concerned... aeration was the issue. I.e. because you are boiling the hell out of your total wort volume in all-grain (i.e. depleting it of oxygen), you must remember to put it back in after cooling. This is not really an issue with partial mashing because the oxygen depleted wort only makes up about half your fermenting volume, the rest you make up with cold, oxygenated water.

And you can pour the top up water from a height to give even more oxygen!

 

[mashdog]

Hi Mashdog,

When you brew with extract or partial mash you should be using cool BOILED water, which has also had the oxygen driven out of it and doesn't easily take it back. I can tell you, and I'm sure I'm not the only one, that one of my main problems with off flavours and poor stability was using cold tap water to top up my brews. It comes with its own flora, even if chlorinated.

MFS.

Yeah i've just been using 10L or so of cold (refridged to 4degC) puratap water. Might start boiling it before fridging as you suggest.

Cheers.