Why Erlenmeyer Flasks for Starters?

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superslomo

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I don't have any flasks, so have just been using mason jars to do starters. Is there any particular advantage to the erlenmeyer flask for starters, if you alternately have canned sterile wort? We have loads of mason jars, and a pressure canner, so it seems like this would be an easier way to go.

Anybody care to "learn me" somethin' here?
 
I don't see why not, my first advice on getting started with starters was to use a growler and swirl it whenever you walk past.

I think an Erlenmeyer flask is ideal for a simple stir plate setup because of the flat bottom and the graduations on the side, and you kind of get to look like a mad scientist when you use one.
 
Advantages I can think of:

- able to boil directly on the stovetop and go right to an ice bath for cooling.
- flat bottom for use on stirplates.
- foam stoppers are made for them (if you don't to use foil)
- you look like a mad scientist
 
You can boil your wort in them directly over the flame of a gas stove.

+1 to this, this makes it super simple

I don't know how much of a concern this is, but I was warned when buying my flask at my LHBS that the glass "Isn't what it used to be"

I have had no issues heating over the gas, but there are no brand markings on the flask, so I am cautious when I use it.
 
you can put the flask in a water bath (pot with water) and boil that if you don't have a gas stove... as long as the flask you bought is made of pyrex you will be fine. They are made to be autoclaved which takes place at a high temperature under higher pressure than normal so you won't have any chance of being able to blow it up ;)
 
Mason jars also can be pressure/steam treated, so I would assume they would fit the bill as well? If you pressure can wort, that would eliminate the advantage of an erlenmeyer, at least as long as you don't have a stirplate (I don't)?
 
Mason jars also can be pressure/steam treated, so I would assume they would fit the bill as well? If you pressure can wort, that would eliminate the advantage of an erlenmeyer, at least as long as you don't have a stirplate (I don't)?

Right, the best advantage of the flask is not having to use the pressure cooker. If you will be using that anyway, then mason jars are far more economical.
 
Pyrex is a Corning brand name for borosilicate glass, however many other manufacturers also make borosilicate. Kimble-Chase's brand name for it, for instance, is Kimax. Any Fisher Scientific branded Erlenmeyer flask will also be borosilicate. Most erlenmeyer flasks, because they are often used for heating aplications will be borosilicate even if unmarked, but that is not always true. Borosilicate has great heat tolerance, and more importantly is quite tolerant of sudden changes in heat. It's not impervious, but will be harder to break and lose your starter than a mason jar.
 
If you aren't boiling it in the mason jar, but just putting it in the pressure canner to sterilize, then it isn't an issue is it?
 
I can/jar wort in mason jars, I process them at 10 PSI for 20 minutes. Never had a problem other than a couple older lids that wouldn't seal well.

I still use erlenmeyers for yeast as the flat bottom makes things simpler. I do a gas-burn of the lip of the mason jar when I transfer to the sanitized erlenmeyer.

M_C
 
I use both, I can my wort but only just so I can store it, I will decant off the hot break (you get another smaller one some times when you can wort) into my flask, I then add a foil lid and pressure cook the lot. I then add the stir bar that has been sitting in iso-propyl alcohol and cool it all. This allows me to have a totally sterile wort. Note this only works with my 1L flask when it has 700ml of wort as any more won't fit in my pressure cooker.:mad: For larger starters I use anything I can find without my stir plate, I so have to get a 5L flask

Clem
 
Advantages I can think of:

- able to boil directly on the stovetop and go right to an ice bath for cooling.

Dumb question, I have always boiled in a pot and then transfered to my flask because I was afraid of moving boiled glass into an ice bath. Is it safe to do this?


- foam stoppers are made for them (if you don't to use foil)

I personally hate using foil and would prefer a stopper and airlock. If I inject pure oxygen through a stone, would I be okay to do this?
 
Dumb question, I have always boiled in a pot and then transfered to my flask because I was afraid of moving boiled glass into an ice bath. Is it safe to do this?




I personally hate using foil and would prefer a stopper and airlock. If I inject pure oxygen through a stone, would I be okay to do this?

Yes to both.

Another thought on mason jars -- they do have a wider top opening, of course, so a little extra care should be taken when moving it and while the top is off to ensure that bad beasties don't sneak in. However, if you're an experienced canner you're already better trained in that than most homebrewers.

And finally, you'll need a lab coat and thick black glasses for the mad scientist look. :mug:
 
I used mason jars before I got my flask. The problem I had is that I use a stir plate and the bottom of the mason jar is not flat. That caused problems keeping the stir rod stirring. I then used a wine decanter (shaped much like a flask) which has a flat bottom. However, it holds less than 1 liter. I boil my wort for the starter in an All Clad pot then pour it into the flask after cooling it by setting the pot in a larger pot of ice. This is my preferred process. I would not feel comfortable putting my flask directly on the gas stove.
 
I'm confused here... why would you use an airlock (way of keeping oxygen out) and use a stone to inject oxygen?
 
you can put the flask in a water bath (pot with water) and boil that if you don't have a gas stove... as long as the flask you bought is made of pyrex you will be fine. They are made to be autoclaved which takes place at a high temperature under higher pressure than normal so you won't have any chance of being able to blow it up ;)

Can't you put the flask directly on a glass cooktop?
 
I'm confused here... why would you use an airlock (way of keeping oxygen out) and use a stone to inject oxygen?

Because there's a lot of stuff in the air besides oxygen. I'd prefer to have just oxygen in my starter.

It may be an unfounded concern, but I've always been worried about having an infected starter ruin a beer. If foil is good enough for a starter, why don't we just put foil over the top of our carboys?

Maybe it's just me wanting to play with my new toy (aeration system) as much as possible, but I don't see the point of taking a chance if I don't have to.
 
I'm confused here... why would you use an airlock (way of keeping oxygen out) and use a stone to inject oxygen?

An air locks primary function is not to keep O2 out but to keep air (dust and associated microbes) from being freely transferred. Yeast growth needs O2 + nutrients + sugar. Sugar and nutrients are fixed, by the starter but we can add more O2 to our starters to get more yeast production.

Even if air is pulled through the air lock then it is washed ie most of the dust will and hence the microbes stay in the water, this is why some people put cheap vodka and such in their air locks so it is even better at killing the wee-beasties.

Clem
 
+1 Look like a mad scientist.

P1140007-2.jpg
 
you can put the flask in a water bath (pot with water) and boil that if you don't have a gas stove... as long as the flask you bought is made of pyrex you will be fine. They are made to be autoclaved which takes place at a high temperature under higher pressure than normal so you won't have any chance of being able to blow it up ;)

I've tried that... Didn't work for me. Made a huge mess... Hot break literally shot out of the flask and all over the stove. To me the only advantage of using a flask is the flat bottom for use with a stir plate.
 
Hot break literally shot out of the flask and all over the stove..

Control the force you must hmm (in Yoda like voice).... or use fermcap.

I'm still debating on breaking my personal Reinheitsgebot and using fermcap.

If I'm making a starter without using canned starter, I boil it first to get rid of the hot break transfer it and boil it again in the flask to ensure sanitation I prefer heat to sterilize rather than chemicals. It is also easier to then see how much yeast you have accumulated vs trying to tell what is hot break and what is yeast.


Clem
 
+1 on control

Boil overs happen in starters just as they would in a real batch of beer.

Can't you put the flask directly on a glass cooktop?

I would Imagine that you could. But in the lab I work in we always use water baths. I imagine that putting a towel underneath the flask (in the water obviously) would keep the air bubbles from disturbing the flask. You could try it, but I would be careful the first time.
 
DO NOT heat your flask directly on an electric cookstove (coil element or flat glass top). It is dangerous because the surface will heat unevenly. You can explode Pyrex/Kimax glass if you do this. You can use a coil of thick steel wire between the flask and the glass cooktop/element if you do not want to boil it in a saucepan of water.

Point of fact: It is such a commonly held myth that Pyrex or Kimax are borosilicate glass that anyone can be forgiven for thinking this. Pyrex used to be made of borosilicate glass because of its low heat expansion, but it is very brittle. For this reason, modern day glassware made for these purposes is made of tempered soda lime glass. It is much more durable and is therefore a good compromise. I learned this at the Corning Museum of Glass in Corning, New York.
 
Commercial Pyrex cookware is no longer borosilicate, but Pyrex and Kimax lab ware are still made from borosilicate. It was one of those things where Pyrex became a better known brand name than Corning, so they started using it for all their consumer glass.
 
DO NOT heat your flask directly on an electric cookstove (coil element or flat glass top). It is dangerous because the surface will heat unevenly. You can explode Pyrex/Kimax glass if you do this. You can use a coil of thick steel wire between the flask and the glass cooktop/element if you do not want to boil it in a saucepan of water. .

what he said :)
 
Because there's a lot of stuff in the air besides oxygen. I'd prefer to have just oxygen in my starter.

It may be an unfounded concern, but I've always been worried about having an infected starter ruin a beer. If foil is good enough for a starter, why don't we just put foil over the top of our carboys?

Maybe it's just me wanting to play with my new toy (aeration system) as much as possible, but I don't see the point of taking a chance if I don't have to.

From mrmalty.com: "Q: Should I add oxygen to my starter?

Yes. You'll get far healthier yeast and far more yeast growth if the yeast have oxygen throughout the process. Adding oxygen at the beginning helps, but the most effective starters provide a continuous source of oxygen. Oxygen is critical to yeast growth. Not providing any oxygen to the yeast can have a long-term negative impact on yeast health. Yeast use oxygen to synthesize unsaturated fatty acids and sterols, which are critical to creating a healthy cell membrane and good cell growth. With oxygen present, yeast convert sugar to carbon dioxide and water and they grow rapidly. With no oxygen, yeast create alcohol, grow far more slowly, and reach a lower total mass of cells.

There are several ways to add oxygen: intermittent shaking, a stir plate, pure oxygen, or an air pump with a sterile filter.

A stir plate is perhaps the most effective method. When using a stir plate, don't plug up the starter vessel with an airlock. A sanitary piece of aluminum foil or a breathable foam stopper is all you need. Bacteria and wild yeast can't crawl and a loose fitting cover will allow for better gas exchange.

Shaking the starter as much as possible, every hour or two, makes a large difference in the amount of yeast growth and health. With enough attention and good air exchange, shaking is just about as effective as a stir plate.

Continuous air from a pump and sterile filter can be effective too. The major drawbacks are being able to control the flow of air to prevent excessive foaming and evaporation of the starter. Shaking is just as effective as intermittent aeration with a pump.

Continuous pure oxygen from a tank or oxygen generator is both expensive and unnecessary. "

I use foil on my starters and carboys all the time, let's gas go out and nothing to fall in. The only time I would feel uneasy about using foil is if I had a fruit fly problem, they unlike wild yeast/bacteria can crawl past your foil into your beer. But then again, they can also get into an airlock.
 
I put foil on this batch of starters for dubbel and tripel. Boiled wort each time, and left it in the hot pot to cool, with starsan squirted on the pot-lid before covering. Each time I removed foil, I spritzed it with Starsan before putting it back on... For all the junk I've had to buy/acquire and fill the basement with, I'm trying to keep this as uncomplicated as possible.
 
Dumb question, I have always boiled in a pot and then transfered to my flask because I was afraid of moving boiled glass into an ice bath. Is it safe to do this?

Depends on the glass. If you spent some good money on lab grade stuff borosilicate (sp?), then chuck it from boiling to ice and it'll be fine. I bought a $20 2L flask (still the good glass but obviously not high-end stuff) from Northern Brewer and still do this with no problem.

I was cautious at first - did the pot thing and then funnel into flask, then ran cool water over the flask first, now I full-fledge take it from boil to an ice bath. No problems.

I personally hate using foil and would prefer a stopper and airlock. If I inject pure oxygen through a stone, would I be okay to do this?

I may be wrong, but you don't want a stopper/airlock on a starter. The objective isn't creating a good tasting 2L batch of beer...it's to multiply your yeast count and ensure viability. It doesn't matter if the starter gets oxidized later...just chill, decant, and pitch only the yeast slurry. I oxygenate my batches of beer, but never my starter. I use a foam stopper in my flask.
 
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