3 replies to this topic

[consumptionjunction]

Please bear with me!Just a little bit of background: in the past I have made starters by boiling up the wort on the stove in a pot, cooling in the sink with an ice bath, pouring into a gallon jug, pitching the yeast, and shaking the s**t out of it. I've also used an aquarium pump at times but never noticed much loss of wort through foaming (more to come on this issue later). My results have been quite favorable.I just made a stir-plate and got a few erlenmeyer flasks (1L and 4L). I went about making this starter but soon realized that I wasn't 100%. I should have my [mod edit] head examined, going on a plan like this when I wasn't 100% ; ). Needless to say, I became a bit flustered when things weren't going so well. First of all, when using the erlenmeyer flasks on an glass-covered electric stove, is it okay to just put the flask on top of the heating unit? I thought this was a little risky and decided to heat the flask by putting it into a bath of boiling water. As expected, this took a long time, but what worried me most was that the wort was simply not hitting boiling temperatures. I didn't trust sanitation for a second using this method, so I said [mod edit] it and threw it on the glass stove. Nothing happened, no cracks or explosions, so I'm happy about that, but is this okay, or should I stick with boiling in the bath? (The process of boiling was also quite nerve-racking, as the flask was rattling from the oxygen bubbles beneath it. I though that this might lead to a weakening of the flask as well.) What other cost-effective methods are out there? (Of course I could still use a SS pot and transfer, but I like the idea of minimizing transfers.)I then put the flask in an ice bath for it to cool, and, once cooled, began aerating with the aquarium pump. I soon noticed that there was way too much liquid loss. I went from 900 mL to 700 mL before I called it quits. I ended up throwing more wort on the stove, boiling it, and adding it to the flask. I let that cool again and pitched the yeast. This brings me to my second question: how do we (on the forum) oxygenate our starters? I am going to get a SS diffuser soon from morebeer, and I think this will remedy this problem. But I've also heard that there is continuous oxygenation from simply using the stir-plate. Is this true? Do we even need to oxygenate when doing starters on the stir-plate? (I don't have a lid for the flask, so shaking method is out of the question.)As a hilarious aside, when pitching the yeast from the Wyeast Smack-Pack (first I put the pack and scissor in some star-san), I clipped the corner and, low and behold, the little corner clipping popped straight up and into the opening of the flask! (Think Seinfeld and the Junior Mint episode.) Luckily it was sanitized, but this still made me quiver. I decided not to touch it until I threw it on the stir-plate. Of course, that little clipping kept getting in the way of the stir-bar, preventing it from spinning. I didn't know what to do at this point, and perhaps lacking proper judgment, I started sanitizing knives and trying to get that clipping out. It must have been 2 or 3 minutes before I got it out. I'm going to let it ferment out, cold-crash it, decant, and taste the liquid. If it was infected, how would I know at this point?As a second aside, the stir-plate has been running quite well for the past 21 hours without any overheating problems!Any advice here is greatly appreciated!Mod edit: Please watch your language.

4. Vulgar, violent, shocking, profane, or explicit sexual images and/or language are prohibited. This includes the posting of external links to such material. Efforts to circumvent the language filter by intentionally misspelling words are not allowed. PG13 material is tolerated in the PH, but avatars, images, and language outside of the PH will be moderated to a professional office environment level.

[Fatman]

Your flask are probably borosilicate (Pyrex, designed for direct heat from lab Bunsen Burners) - directly on the stove is fine. Just watch for a TOO quick change in temp - i.e. off the stove into water bath to cool.Stir Plate gets you all the Oxygen you need - no need to shake/airate.

[MtnBrewer]

First of all, when using the erlenmeyer flasks on an glass-covered electric stove, is it okay to just put the flask on top of the heating unit?

Never done this on an electric stove but I put my flasks over the burner on my gas stove. You only need to heat it to a boil and then you can cut the heat off and let it stand for 15-20 minutes before cooling it.

This brings me to my second question: how do we (on the forum) oxygenate our starters?

Different people do different things. I use a stir plate. Other people use aquarium pumps. Before I got a stir plate I hit it with pure O₂ about every 15 minutes for the first hour.

[zymot]

Two biggest sources of homebrewer nervosa:Is my starter big enough?Is my beer infected?My opinion (a minority opinion) there is way too emphasis on starters and yeast pitch rates. So many variables involved. One big variable overlooked is that making a starter from a smackpack or vial is not the same as a starter from a recycled yeast cake. Check out the starter calculator on Wyeast web site.Do what you can with the resources available to you.I know from anecdotal information, putting flask directly on a electric stove coil is asking for trouble. The coils create hot spots and cold spots between the coils and stress the glass to the point of cracking. Does a glass top stove diffuse the heat enough? I won't say. Use your best judgment. I use a cheap single burner propane camp stove out in the garage. Saves me the trouble of the wife coming into the kitchen to complain about the smell.

This brings me to my second question: how do we (on the forum) oxygenate our starters?

I use a tube on my bottle of oxygen and put it into the flask of wort. I get the stirplate spinnng as fast as I can to get the vortex down to the stir bar. When this happens you can see all kinds gas getting infused into the wort. If the flask is rich with oxygen, then the wort must be getting infused with oxygenThere was somebody on the other board that did dynamic tests with a disolved oxygen meter. He found agressive stirring was more effective than a diffusiom stone. Because the tube, high stirrring method is easy to do, I go with that. The results I have observed tell me this is a very good way to go.zymot