Yeast Starters

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Doctor's Orders Brewing
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This is an interesting little article.
It is American so uses all their products and terms, but I'm sure it could easily be adapted to what we have available down here.
I documents the process of using your microwave to get some wort ready for a yeast starter.
Check out the link here.

Doc, I can't get that link to work. Do I need tosubscribe to the site or something?
The HBD appears to be down today.
They had problems with the forum last week too.

When it comes back up I'll post the article here.

Ok, from googles cache here is the text.
The diagram is missing. I'll post the diagram when HBD comes back online.

Microwave Yeast Starter Preparation
C.D. Pritchard - New, 8/14/99

As anyone who has tried to make starters in the microwave knows, they can boil over and make a mess if not constantly attended for the duration of the boil. Even then, they can't be boiled too hard.

An additional problem is how to ensure sanitation as the starter cools. The following method solves both of those problems. Making the starters with the method is very easy and doesn't require constant attention.
Here's a drawing of the starter making jar:


The lid is made by Ball and is available in a package of 6 (as I recall...). They are available at Wal-Mart. It's made of polyethlene so it'll just a little bit soft during the boil but withstands it just fine. Modify it by cutting a 1 3/8" diameter hole in it's center. I used an X-acto knife and finished the raw edges with sandpaper over a piece of 1" PVC pipe- going down to 600 grit to avoid deep scratches which are said to harbor bacteria and such and which cause stress risers which could lead to cracking. (Maybe a bit too anal, but it doesn't take long.)

The stopper is the smaller one (cat. # Q38) available from Williams Brewing <> (a good outfit IMHO). Only 90 cents. I think it's made of silicone since it takes the steam from boiling well and allows the steam from boiling the wort to escape easily while at the same time sanitizing it. What I like about it is that it's said to block or trap any nasties that might enter the jar during cooling. (I used to use plastic wrap over containers for boiling and was surprised by the amount it bows in during cooling- with too much head space, it'll actually pop.)

The key ingredient in the method is Foam Control (cat. #CMIM, $2.50 for 2 ozs). Order at: HopTech <>.
I know, it's intended for use during fermenting and not boiling, but, it works great- absolultely no foam when only 2 drops are used in 20 oz of wort.

The jar is a typical one quart mason type canning jar.

Start with about 20 oz. of warm water in the jar. Add DME (dry malt extract). Try not to get it on the lip or sides of the jar- I use a tablespoon to add the DME. (I've not used hops, so, you're on your on if you do.) Attach lid with stopper and put in microwave set on high. When boiling starts, stop the microwave, tighten down the lid and then resume but at reduced power setting. Although there is not a standing head of foam, violent boiling will, at the least, spray the stopper with wort as the steam bubbles collapse at the surface of the wort. 40% power for about 10 minutes works for me. I then remove it from the microwave and let it air cool for at least 15 minutes then put into a container of hot tap water. After 10-15 minutes, replace the hot water with cold tap water. I know this could cause the jar to break due to thermal shock, but I've been canning dill pickles this way for years and have never had one to break. Of course, just letting the jar air cool will work, but, when you want yeast started ASAP or you're just plain impatient like me...

It might be hearesy, but I currently don't do anything to aerate the wort after cooling other than to swirl it a bit after the yeast is pitched since I've not come up with a simple areation method that I feel comfortable with sanitation-wise.

Here's another neat thing about the method- with the ~10 minute boil, the foam control survives and virtually eliminates a krasuen head in the starter jar- only a few tiny bubbles accumulate with the starters I've made. For smaller starter volumes, an Erylemyer flask works well since you can swirl the starter better than in a mason jar which makes for better aeration.

Some things that might be worth considering if you're of the gadeteering bent:

1. A magnetic stirrer would be nice. It would increase aeration initially. One set up on a timer would increase the yeast production rate.

2. A drip type wort feeder would be nice to play around with if sanitation could be assured and it was designed to prevent plugging by any trub.

3. Combining the above with a gizmo for automatically drawing off the spent brew after the yeast has settled a bit (a opacity sensor using a infrared LED and photo transistor maybe?) would allow for continious production- i.e. an automatic, continious fermenter!

If anyone does 2 or 3 or has any ideas about them, I'd be interested in hearing from you... click here: [email protected] <mailto:[email protected]>

1. I've no idea what, if anything, boiling the foam control does as far as producing nasty stuff in the starter, but I routinely sample the spent brew to judge the yeast and (unless it results in having to have a root canal!) haven't had a problem...

2. A test of the sanitation of the method is needed, but I've been too lazy. I fiqure prep. a starter, don't pitch any yeast and see how long it takes the starter to go bad. There's a name for this method but I can't recall it (maybe boiled foam control causes memory loss

3. This method is fraught with all sort of potentialities which can maim, kill, or otherwise injure you or your health. Use with wisdom and common sense but at your own risk.

4. The info is liable to be worth exactly what's it's cost ya! (grin)
No worries.
I've now updated the post to include the diagram.
HBD appears to be up again.
As long as HBD is up the diagram will also appear as I have linked it to HBD.
Seems when you edit a post you can't add an attachment.

I'm keen to give this a go.
Here is the diagram of the jar as HBD looks like it is having problems again.
Has anyone tried this ?