Archive for the 'Will It Ferment?' Category
I had to do a Fred Transplant last week. A grey fuzzy mold had taken up residence in on the sides of the jar above Fred’s liquid culture, so I set up a fresh container with fresh water and flour, and dipped a spoon down the center of Fred to the bottom, pulling up just a tiny amount of the stuff in there. Then I mixed it into the fresh stuff and covered it with plastic wrap (instead of a paper towel this time.)
Fred smells like Swiss Cheese Feet right now, but he’s obviously still growing, as you can see from last night’s “Gram Stain” microscopy. The slightly blurry light-red-brown lumps are, I believe, yeast cells, possibly Saccharomyces boulardii, since I dumped a capsule of supposedly-still-viable “probiotic” yeast of that species into Fred previously. I have no idea who the bacteria are in here at the moment. I did also see a small number of longer, thinner bacterial cells in there (presumably Lactobacillus) though most of them are the ones you see here.
Meanwhile, I’m about to dig out the still-unused Hillbilly Autoclave and try it out on the media I’m mixing up to try to obtain a culture of genuine wild “native flora” vinegar/kombucha yeast-and-bacteria to play with from the local wildflowers that are just now getting into full bloom.
My starting recipe goes something like this: I mix up about 2 Liters of distilled water with about 100g of glucose (“Dextrose”/”Corn Sugar”), 100g of sucrose, 500mg of L-Arginine, and enough phosphoric acid to drop the pH down to about 5.5 to 6.0. That is intended to be then poured into small “canning” jars in about 100ml amounts and pressure-cooked for at least 15 minutes to sufficiently sterilize and seal them. Meanwhile, a single generic-brand children’s chewable vitamin is crushed up and dumped into a 4-oz bottle of cheap vodka and well shaken.
Then when it comes time to go bioprospecting, I’ll pop open the jar of acidic sugar solution and add about 5ml of the cheap-vitamin-vodka to it to give me about 2% ethanol, and then go find some flowers to cut off and dump into the jars, which will be loosely covered with foil (to let air in but keep dust out) and put in a nice quiet cupboard to grow for a few days.
Hypothetically, the only things that are likely to grow in that will be microorganisms associated with vinegar-making. At some point I’ll also make up a batch of sweet black tea and see if I get a kombucha-like culture going in it, and make up some solid media to try to isolate individual microbes from it.
They say “When life gives you lemons, make lemonade”. What if life gives you snot instead?
Now, see, this is what happens when I’m too poor to buy nice distracting new toys for myself. (No, not the hand in the picture – that’s not mine, it’s just there for illustration.)
I found a pot that I’d rinsed well but then left filled with water in the sink to soak, to help remove the last of the rice bits stuck to it. It hadn’t gotten stinky or fuzzy or anything, but it had gone…viscous. Like a light sewing-machine oil. Naturally, I took appropriate action to deal with it.
I fed it.
Glucose (“dextrose”), to be precise. It’s since been dumped into an old glass jar and the original pot thoroughly scrubbed with hot soapy water. At this point (a day later) the slime is closer to the viscosity of vegetable oil now. And I fed it again.
I wonder what it is? I mean, obviously it’s bacteria-snot, but what kind? I suppose if I had some iodine I could check to see if it’s a polysaccharide (evidently this test works on polysaccharides besides starch). If only I had a microscope, I could at least get some basic hints as to what’s producing the slime. Maybe I can maintain a culture and figure it out later, if I can ever afford a real microscope. Perhaps I could even attempt a strain-improvement program to increase the production rate…
Uh…I did mention I was a nerd, right? Okay then.
I wonder if anyone at work has a bacteriological microscope setup that I could use?…
According to the nutrition information on the back of the bag and some quick calculations, powdered Xanthan Gum has a density of a little over 610mg/ml (or about 10 slugs/hogshead).
I think I may be an Applied Microbiology nerd.
See, when I put dirty dishes in the sink to wash later, I often fill them up with water to soak. I didn’t see this much in Idaho, but down here in Texas I notice that if I leave them too long, the water will sometimes end up turning into a thick slime.
And here I am, wondering what kind of slime it is and if I could find a way to produce it in quantity and purify it (and then find something useful to do with it).
I’m also wondering if this delightfully simple gel electrophoresis technique might be scaled up for more production-type purposes.
In my last submission to “The Giants’ Shoulders” blog carnival, we saw how the famous surgeon Dr. Joseph Lister deftly demonstrated definitively that fermentation processes were caused by live microbes rather than some sort of mysterious soluble substance that just happened to be associated with microbes. In today’s episode, we will see how Eduard Buchner definitely demonstrated that fermentation was caused by a soluble substance that was associated with microbes, and no microbes are actually needed.
Better still…they’re both right. “Wait…what?” Read on, O Seeker of Microbiological Knowledge, and be enlightened by this month’s entry: (more…)
Did I mention the place I work has some amazingly spiffy perks for a nerd like me?
Last night, I was poking around pubmed looking for references to yeast and erythritol (namely, do yeast interact with it, and will they metabolize it?) I found precisely one relevant reference. From 1975. In a Czechoslavokian microbiology journal. A no-longer-existent Czechoslovakian microbiology journal. Even though it was a journal published in English, I didn’t figure I’d be able to find the article I was looking for. It did turn out that the greedy (insert long string of profanity here) anti-open-access “SpringerLink®” Netherlands organization has an electronic copy of the article…which I can get limited access to for a short time for a mere $34.00. Not going to happen, obviously.
Just in case the college had a subscription that would let me get to the article at no extra cost, I checked. No such luck. But…
…The campus medical science library just two buildings over from where I work has dead-tree editions of essentially the entire journal! Im name des Nudelmonster! Instead of paying $34.00, I got a photocopy of the article for about $0.50. Bonus: As I had hoped, the article reports that erythritol is not metabolized by yeasts, although it is taken up to a small extent. That means I can add erythritol (or xylitol or sorbitol or whatever) to must or wort, and it’ll still be there when the yeast finish, leaving the resulting beverage still sweet. Hooray!
Plus, I was also able to get access to an electronic copy of a review of the uses of poly-?-glutamate, which I was bemoaning not having access to over on an interesting Small Things Considered post recently.
Speaking of reading, one thing I really could use are any worthwhile books on the general subject of applied/industrial microbiology, bioprocess engineering, fermentation, and so on. “Worthwhile” here means practical texts that are A)primarily about microbiological processes (as opposed to, say, bioengineering of plants) B)Reasonably technical, and C)Either “not very old” or “very old indeed” (I collect old science books).
I’m not a fan of Amazon.com’s abuses of the patent system, but I’m in a hurry since it’s past my bedtime already. Therefore, purely as a sampling of the kinds of books that sounded interesting to me, here is a selection in more or less random order of books that came up in a quick search on amazon.com. Anybody out there have any other suggestions?
Dr. Joseph over on the “(It’s a…) Micro World (…after all)” blog posted a list of his ten favorite microbes. After showing up in the comments of his post and being a wiseass about E.coli and Gram staining, the least I can do is participate here. Besides, it’s a great idea. Therefore here are ten of my current favorite microbes:
Lunchtime – time to get this posted…(Let me know if this page is loading way too slowly…)
For this month’s “Giant’s Shoulders” I offer you mouthwash and yogurt.
Indirectly, at least.
Today’s batch of blog-based Stir-Fried Random includes another interactive map of a lake-spanking expedition, a very brief musing on search engines, and a return to “intentional food microbiology” discussion. To preview: you can get pizza without ever getting out of the water on Lake Conroe, “spanking” is amusingly popular for search engines, and no, there is not normally any yeast in ice cream, but perhaps there could be. Read on, please…
<whine excuse=”obligatory”>Have I ever mentioned what a huge hassle it is to relocate from one abode to another 1600 miles away?…</whine>
I’m finally back at House v1.0 where I can check on the progress of my Mountain Dew® Wine. It appears to have managed to ferment, in spite of the severe dose of preservatives in the stuff designed to prevent that from happening. It went somewhat slowly, but it’s gone from an original gravity of around 1.054 down to about 1.011 or so, suggesting about, say, 5-6% alcohol in the final product, which has faded to a pale, cloudy yellow color. Hopefully the cloudiness is from still-living yeast, which has now demonstrated that it is reasonably benzoic-acid-and-caffeine tolerant.
I fear I must report that the result is a crushing disappointment to me. It’s not very good. Worse yet, it’s not very bad, either. I was hoping that if it wasn’t surprisingly tasty that it would at least be shockingly awful in some interesting way so I’d have something entertaining to say about it here.
Actually, the adjective that comes to mind is “inoffensive”. If you would like to whip up a quick simulation of what I’ve got here, you might be able to do it like this: Take some citrus-flavored sparkling mineral water. Dilute it about half with (uncarbonated) distilled water. Then mix about 7 volumes of that with one volume of vodka. What I’ve got here is slightly sparkling, with a barely noticeable citrus flavor and little or no remaining sweetness. It’s a little surprising to me just how much of the flavor of Mountain Dew® apparently comes from its sweetness. Perhaps next time I try this (if there ever IS a “next time”…) I’ll have to mix regular and “diet” Mountain Dew® – with some bonus sugar to make up the difference, of course.
I’m not completely done here. I’m still going to dispense it into cleaned bottles with a little bit of sugar to prime it for full carbonation. Sanitized plastic soda-bottles of course – none of that snobby glass stuff for this here experimental drinkin’ substance! It may be high-class for “pruno”, but it’s sure as heck not Champagne™. (Besides, I want to evaluate reusing plastic bottles anyway – it’d be a lot easier to tell when there’s too much pressure and to let some of the pressure off if there is.) Plus, I need to take some of the still-live yeast and keep it alive. No point in developing a benzoic-acid-tolerant yeast strain and not keeping it!
On a related note, an article was mentioned on fark.com, saying that back in 1955, a scientist “proved” that it is not normally possible to get drunk on beer. Of course, he seems to have been referring to dilute mass-market bladderwash and his reasoning was that a typical human stomach cannot contain enough 3.7%-alcohol beer for a typical human to achieve a dangerous blood-alcohol level.
As usual, the articles (see here and here) go for the “a scientist says this” part but never bother to say WHERE the scientist says it – usually a real scientific publication.
A quick search of pubmed turns up a likely candidate:
Greenberg LA: “The definition of an intoxicating beverage.” Q J Stud Alcohol. 1955 Jun;16(2):316-25 (link goes to the pubmed entry, which has little more information that this).
I do believe it is a moral imperative that I get a copy of this article somewhere so that I may reference it later. Is there anyone out there reading this who might be able to get a copy of this paper somewhere for me? Please?…
Sorry about having another brief bout of blogstipation. We’ve finally managed to close on a house and now we’re probationary Texans (y’all). I’ve been spending the last week+ driving back to SE Idaho (by way of Best Friends, since we now have room to hire a second dog to hopefully keep Cornelia the Laser Dog company. I’ve got to lug 3 cats (and one goldfish in a small fish tank) a distance of 1600 miles or so starting in about 6-8 hours. Wish me (good) luck.
After the weekend, I should have some time to get back to the real posts. The Mountain Dew Wine was virtually unfermented when I returned, even after sitting there 10 days, but since I’ve gotten back it’s started going. Still slowly – the bubbler spits out 3-5 bubbles ever 40 seconds or so – but it’s going. It’ll be interesting to see what I end up with. I wanted to do 2-3 posts on the effects of benzoic acid on yeasts (that’s the preservative in Mountain Dew®), and I would swear I had one or two others in mind. Oh, yes, and an update on getting a Magellan GPS replacement that can actually be used – they seem to have located a slightly lower-end model eXplorist that they can send me. I sent them back their “walled garden”-based Triton 500, so the replacement unit ought to show up next week, I think. Their service has been pretty good, at least.