Messages

1666

Yeast and Fermentation / Re: Oxygen; too much, or not enough

« on: November 25, 2009, 02:38:10 PM »

and pressure, but I have trouble controlling that

To some extend you do and it makes a difference. The O2 pressure in air is about 0.2 bar (~3 psi) while it is 1.0 bar (~15 psi) in pure O2. As a result you cannot overaerate with air and at common pitching teemps air saurated water wort is likely around 8-10 ppm. This is different with pure O2 where you can actually overoxygenate the wort. But pure O2 also allows you to get sufficient O2 into high graviy worts where you are limited with the use of air.

Kai

1667

General Homebrew Discussion / Re: Standards for Homebrewing Calculations

« on: November 25, 2009, 02:07:28 PM »

I ask because I would like to develop my own spreadsheet application for recipe design and result estimations.  I know there's a ton of software already written, but even the commercial software packages results seem to vary.

They vary b/c most of them are just estimations. Hop utilization, for example, depends on many more factors than boil time and wort gravity. As a result each of the brewers who came up with a formula found slightly different results. I'd pick one and stick with it.

The only real standard we have is the ASBC (American Society of Brewing Chemists) or EBC (European Brewing Convention) and even those official bodies don't necissarily agree on everything. At least they are close. You can buy books where the standards are defined, but those are expensive and not necessarily valuable to you anyway.

It all depends how complicated you want to make it and how complicated it has to be. Given the precision at which we measure during our brewing process highly accurate formulas might be moot anyway. I suggest that you look around on the web and in the literature (Designing Great Beers might be a good start). If you find differences check how big the difference is and if the authors are making different assumptions.

Kai

1668

Equipment and Software / Re: Draining the boil kettle....

« on: November 25, 2009, 01:57:00 PM »

If you have a bazooka screen or something else that sticks into the kettle and disturbs an even rotation of the wort, you may prevent that nice trub cone to form.

I just brew more than I actually need, chill, let it settle and rack clear wort from the top. The wort/hop/trub sludge at the bottom gets fitered through a paper towel in a large funnel w/ screen. The clear wort is then frozen and used for future starters. I use a lot of wort for yeast propagation which is why this works well for me.

Kai

Post #100, Woohoo

1669

All Grain Brewing / Re: Various water recipes

« on: November 25, 2009, 12:31:21 PM »

Not unless it's a porn forum! 

They have those   




(insert reference to the Family Guy episosde, where Quagmire finds out about internet porn, here)

Kai

1670

All Grain Brewing / Re: Various water recipes

« on: November 25, 2009, 12:02:03 PM »

kai - I don't know if i'll get in trouble posting a link to another forum, but here's the discussion we were having:
http://forum.northernbrewer.com/viewtopic.php?f=5&t=81869

I don't think you should get in trouble. I'm a big fan of cross linking. I'll check it out.

Kai

1671

All Grain Brewing / Re: Various water recipes

« on: November 25, 2009, 11:55:37 AM »

He says that most craft breweries use RO (he's friendly with a lot of the Cali and Denver micros), and frankly, every brewpub I've been to and brewer that I have talked to uses RO water and adds some back. 

really. I didn't know that. On the other hand I tend to be less in touch with what US craft breweries do than what a German brewery might be doing. For the latter I think that if the RA of the tap water matches what is needed for their beer, the water from the tap will be used w/o modifications. Which is why emulating the local water from a paricular German brewery is oftentimes a good start. But there are exceptions as well.

If Stone is using RO water, I'll have to check with them how they handle chalk in their very dark beers.

Kai

1672

Yeast and Fermentation / Re: Water in yeast plates?

« on: November 25, 2009, 11:42:23 AM »

Do you use a loop or needle to inoculate your stabs? With visible yeast on the one you use? Thanks for posting the log book.

to make a stab, let the agar set w/o resting the vial at an angle. Then take a sterilized needle and stick it into one of the colonies on the plate. After than just stab it a few times into the agar and let the culture grow a little before putting it into the frigde. I don’t think it matters much if you have visible yeast on the needle. I usually have a little bit.

 

Some are now as old as 3 years.

That means I have been able to keep the culture going for 3+ years. That involves periodical re-culturing. I stop harvesting the lawn once it starts looking brown. That usually happens after 4-7 months. At that point I may inoculate a new slant from the old one, get some yeast from a stab culture or start a plate culture from which I inoculate a new slant.

My oldest yeast is a culture of WY2206 and sometime in the future I want to brew a side-by-side with that yeast and a fresh yeast pack from Wyeast. I’m curious if I can detect taste and or fermentation performance differences.

Kai

1673

All Grain Brewing / Re: Various water recipes

« on: November 25, 2009, 11:32:57 AM »

Building water from scratch is really a home brewer only thing. I think only few commercial brewers would want to go that route given the capital investment and the amount of waste water produced by an RO system.

But building water adds so many more knobs that a homebrewer can turn and this can be rather daunting for beginners. When I moved to the new house and started using RO water I didn’t know want to aim for either. So many choices. In the end I actually started emulating the water I had in North Carolina b/c it had worked so well for me. Later I gained a better understanding of water chemistry and figured out what is important and what not.

But having a collection of basic water recipes for a handful of different styles should help many who want to or have to build water from scratch but don’t know where to start.

1674

All Grain Brewing / Various water recipes

« on: November 25, 2009, 09:32:20 AM »

A number of people have asked me to publish some of the water recipes I'm using. I guess b/c I talk so much about water.

So I decided to do that here: http://braukaiser.com/wiki/index.php?title=Various_water_recipes

But don't get the idea that these are highly optimized and elaborate recipes. I generally only care about residual alkalinity and hardness. When it comes to hardness I prerfer softer water but have yet to make a side-by-side with waters that have large diferences in their hardness.

See them as starting points.

Kai

1675

Yeast and Fermentation / Re: Water in yeast plates?

« on: November 25, 2009, 09:27:49 AM »

Nice. once thing, that makes me more comfortable is taping around the cap. This way nothing gets under the cap and closer to the opening of the vial. Not that it can get into the closed vial but I like to keep the other bugs away as much as it is reasonable.

I also made a log-book for yeast in which I can record how I have been propagating a particular strain. Here is a PDF: http://www.braukaiser.com/documents/logbook_yeast_bank.pdf. I just started using this form but have been keeping track of my cultures ever since I started yeast banking. Some are now as old as 3 years. This is the time since I cultured them first and not the age of a prticular culture. I found that stab cultures make a nice longer term storage than slants while with slants I can easily scrape off some "lawn" and start propagating from that. As a result I now keep one stab and one slant for each yeast strain I have.

BTW, one of the Weissbier bottle dregs I brought back from Germany is finally showing yeast growth. I now have to propagate enough to make a small sample fermentation with it.

Kai

1676

Beer Travel / Re: Lay-over in Munich

« on: November 25, 2009, 08:39:41 AM »

That Deutsches Museum is AWESOME. I was only in Munich for two days and it rained pretty much nonstop, so I had to find a lot of things to do inside. 

It would have been more awsome if they had a brewing exhibit. After all its in Munich.

But at least I know much more about oil exploration and mining now

Kai

1677

Yeast and Fermentation / Re: < 48 Hr. Primary Fermentation?

« on: November 25, 2009, 08:24:48 AM »

I got the 75F pitching temp from my local home brew store's directions. 

I see that a lot and I don’t like it. Just last night I was asked to double check a HBS’ directions for making a lager which asked for pitching at 75 F (!!!!).

To understand this you have to keep in mind that a HBS’ primary objective is to make the process simple and avoid calls from angry customers when they don’t see fermentation within a day or so. They also look for a method that allows pitching a beer w/o the use of a yeast starter.

But many experienced brewers will tell you that your beer will be better if you ferment slightly on the cool side for the yeast (65-68F for ale and 48-50 for lager) and pitch a few degrees cooler than the fermentation temp. This allows the yeast to get up to speed more gently and they won’t produce as much esters and , which is most importantly, fusels. But to make this happen with a reasonable lag time and fermentation performance you need to pitch more yeast than there is in a vial or smack pack. This is in particular true for lagers. Here is where starters come into play. They are mini fermentations aimed at vitalizing and possibly multiplying the yeast.

You may also use dry yeast where you don’t have to make a starter.

Kai

1678

All Grain Brewing / Re: Magnesium carbonate

« on: November 25, 2009, 07:36:17 AM »

I fond the stuff in health food stores.

Some of the climbing chalk claims to be 100% pure with no additives but I have always been a bit cautious with that. Although, I have breathed my fair share of chalk dust at this point. Maybe I try dissolving it wit CO2 to see if it would actually work.

My tap water has a lot of Mg too, but also arsenic, which is why I use RO water in the first place.

Kai

1679

All Grain Brewing / Magnesium carbonate

« on: November 25, 2009, 07:22:06 AM »

Does anyone know of a source for food grade MgCO3?

It's just a geeky thing, but this is one of the few salts I'm mssing. I have a hard time making true Munich water w/o that stuff since there is a lot of Mg and little Cl or SO4. I know that mimicing that water exaclty doesn't really matter as long as you match residual alkalinity, hardness and maybe the Cl/SO4 ratio. But I'd like to have that salt too. A fellow brewer was able to get me MgCl2, which isn't widely used by brewers either.

Google didn't show much. There seem to be little food uses of that stuff. I have it as chalk for climbing but I don't trust that it is pure.

Kai

1680

The Pub / Re: 1000th member

« on: November 24, 2009, 10:14:10 PM »

118, not too bad. And now I have one more post as well

Kai