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:
Category: Food Science
Did you ever notice that good chemists are very often also good cooks?…
Stir-Fried Random Ep 03: All I Want for Christmas Is…
Thanksgiving = Shopping, evidently. Anyway, since this is about the time of year when the vast population of my devoted fans around the world begin demanding to shower me with gifts and asking what kinds of gifts they should give me…this episode of Stir-Fried Random has some suggestions. Enough suggestions, in fact, that I didn’t even have room to include a Nerd Word, Emprical Observation of the Week, or Microbiology Microlecture. Therefore, while this episode will probably be slightly less interesting to the microbiology and computer-nerd focussed listeners, it should be of special interest to members of my immediate family, secret admirers, cultists who worship me as a living embodiment of divine spiffitude, and agents of the NSA, FBI, CIA, USDA, and Federal Department of Blog Enforcement who are busily profiling me. There is some other stuff though – please give it a listen, pass copies along to your friends, play it over the Public Announcement system at school, turn it into a techno-dance remix video on YouTube®, whatever.
As usual, direct download links for mp3 and ogg versions, plus <audio> tag support for those with really new browsers to listen in place, and embedded Flash-based mp3 player for everyone else who wants to listen in the browser instead of downloading and singing along during your commute or whatever.
(UPDATE 20081126: I’ve REMOVED the embedded player for now – it seems it ignores me when I tell it to wait until it’s told to before it starts playing. Autoplay annoys the heck out of me, and this seems to insist on it. The embedded player will remain gone until I get it to behave properly. Meanwhile, you can double-click or “right-click -> save as:” on the ogg or mp3 download link to get the audio files to listen to. Apologies to anyone ambushed by the unwanted auto-playing of the sound…)
Continue reading Stir-Fried Random Ep 03: All I Want for Christmas Is…
Double-Ewe Tea Eff: “Modified Food Starch”
One of my projects is to appease one of my weaknesses. As I’ve probably mentioned before, “Gluttony” is my second-most-favorite deadly sin. If you’ve been listening to “Stir-Fried Random” (new episode coming shortly, I promise) and reading the blog recently, you can probably tell that among my large collection of “a peculiar fondess for [whatever]” attributes that I possess is one for “Cinnamon Bears“. While they’re not too bad as far as candy goes, they’re still not good for me. Plus, like any candy they can get to be kind of expensive. (Dear Amazon.com: The package plainly says “2/$100“. You’re selling these in groups of 12. Now, I only carried my calculation out to 3 significant figures, but I estimate that this should cost $6.00. Not “$6.85”. Plus $7.90 for shipping. $14.75 for $6.00 worth of convenience-store candy is just stupid.)
Anyway…I’ve gotten my grubby paws on a small bag of erythritol, which is effectively a calorie-free sugar alcohol produced from a regular sugar by a natural fermentation process. All I should need is one or more thickening agents and some oil of cassia and/or other flavors and I should be able to come up with a recipe for my own pig-out-all-I-want, even-better-than-mass-market cinnamon bears. Food is one of the few areas that I seem to have any natural artistic talent with, so I ought to be able to handle this.
The trick is going to be getting the right texture. I’ve found recipes online that use gelatin or pectin. The store-bought product, though, uses “Modified Food Starch”. How exactly do they “modify” the food starch? I vaguely recalled that it was an acid-treatment process that partially breaks up the long glucose polymers, but I wasn’t sure. As any modern nerd would do, I decided to ask My Friend, The Internet.
Most places seem to be vague about what exactly the “modification” is, but it became quickly obvious that there were multiple treatments that result in “Modified Food Starch”. Ah, but I was in luck! The Food and Drug Administration actually has a specific entry in the Code of Federal Regulations, which can always be counted on to definitive. So, I went and looked at good old Title 21, Volume 3 of the Code of Federal Regulations and…WTF?!?!?
They list a bewildering array of chemical and enzymatic treatments that all get lumped into “Modified Food Starch” (or “Food Starch-modified” as they quaintly put it).
I guess my happy new box of “Corn Starch” will have to remain unmodified for the time being. At least until I can figure out how to produce my own ?-amylase [without spitting, that is]. I also have unflavored gelatin and pectin at my disposal here, so I’ll come up with something.
Anybody got a good reference on industrial food processes?…
“On the lactic fermentation and its bearings on pathology.”
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.
Continue reading “On the lactic fermentation and its bearings on pathology.”
Yeast needs to breathe
As readers may have guessed from previous posts, my brewing interests are minimally conventional. Fortunately, the Basic Brewing Radio podcast seems to regularly expand well beyond the usual “fermented malt flavored with a tisane of hops” thing (I need to try to make my own “Ginger Beer Plant” from scratch one of these days…). A couple of weeks ago, they did an episode covering an experiment on aeration methods which was very interesting. It does my ego good to know that I correctly guessed how the results would turn out. You can get a copy of the nice write-up of the experiment itself here, but here’s the simple version:
Aqua-pedestrianism and Ice Cream Yeast
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…
FoodTV’s new “Food Detectives” show…
That’s all I can stands, I can’t stands no more! I had intended to try to come up with another post for this month’s “The Giant’s Shoulders” anthology, but I’ve just encountered such an appalling concentration of disappointing un-science that I cannot restrain myself any further. Guess I’ll have to settle for one post in the anthology this month.
FoodTV’s new “Food Detectives” show sounded so promising. I thought to myself “‘MythBusters’ meets ‘Good Eats’!?!? That would be pure, refined, pharmaceutical-grade WIN!” Then I saw their premier episode. The “experiments” appeared blatantly and badly staged, and in some cases shockingly badly designed. For example, their “experiment” with refrigerator deodorants involved showing a guy sticking his face into a ‘fridge allegedly full of smelly stuff and filming him making faces while they timed how long he pretended to be willing to keep his face in there.
Benzoic Acid Part 2: “Sour Stuff”
Okay, now that the boring review is over with…
Consider the cell. It doesn’t matter what kind of cell – bacterial, archael, fungal, animal, whatever. It’s still a tiny droplet of slightly salty water, thickened by a bunch of enzymes, other proteins, and various other substances floating around in the water. There’s also one other component that makes this a “cell” rather than soup: a bubble made of fatty material that the droplet is wrapped in, called the cell membrane. Depending on what kind of cell you’re thinking of, there may or may not be a “cell wall” made of some sort of rigid material, with the cell membrane inside of it. There may also be more than one membrane as is the case with the classic “Gram negative” style of bacterium, which has a second “outer” membrane wrapped around its cell wall. If it’s a eukaryotic cell, it’ll even have tiny little “organelles” inside itself wrapped in their own little membranes…but whatever. It’s the innermost one, inside of whatever cell wall may be there but wrapped around the cell’s guts, that we’re concerned with here.
Since stuff that will dissolve readily in water doesn’t tend to dissolve well into fats, and vice-versa, the cell membrane not only prevents stuff dissolved in the water inside the cell from leaking out, it also prevents stuff in the water outside from getting in. This lets a cell maintain itself at near neutral pH even if it happens to live in a very acidic environment, or an appropriate level of, say, sodium salts even if it lives in the Great Salt Lake.
This brings us back again to benzoic acid, which you should recall from the previous post alternates between a dissociated hydrogen-ion-and-benzoate-ion form and a combined, netural form in water. You may have noticed that foods preserved with benzoates tend to be sour, like fruit juices or soda. That’s because “sour” is the flavor of acid, and benzoic acid’s ability to be a preservative is only good in acidic environments
Useless Knowledge Break: the German word for acid is “Saurstoff”. Yes, that is pronounced like “sour stuff”, and no, that is not a coincidence.
An acidic environment means lots of extra hydrogen ions (“protons”) floating around. That also means that when a molecule of benzoic acid splits into a hydrogen ion and benzoate ion, it takes less time before another hydrogen ion comes by and the molecule can recombine again and therefore a bigger majority of the benzoate floating around at any moment is in the combined, somewhat fat-soluble neutral form. In that form, it can soak into a cell membrane if it encounters one.
If that molecule drifts through the membrane and gets to the inside of the cell, it may touch the less acidic watery environment there and dissociate into ions again and be unable to return through the membrane. The released hydrogen ions mean the inside of the cell becomes more acidic. As of today (20080806), the Wikipedia entry for Sodium Benzoate cites a single paper from the early 1980’s saying that when the inside of a yeast cell gets acidic enough, it prevents a specific step in the energy-generating process from working. This may be true, but there’s more to the story than this.
Obviously the membrane can’t totally seal the cell off from the outside, or the cell would be unable to excrete wastes or take in food molecules, so there are numerous specialized “transport” proteins that stick through the membrane to allow specific kinds of molecules in and out. Lots of biochemical reactions release hydrogen ions, so there are transport proteins that can shove hydrogen ions out of the cell and into the cell’s surroundings. The problem is that all substances naturally diffuse from areas of higher concentration to areas of lower concentration, so in an acidic environment the natural direction that hydrogen ions “want” to flow is into the more neutral cell. These transport proteins can shove the hydrogen ions in the opposite direction, but like pushing a boulder uphill it costs energy. This seems to be the primary reason that benzoic acid prevents bacteria and yeasts from growing – it makes them waste energy that they would be using for growth just to keep taking the hydrogen ions that the benzoic acid helps leak in through the cell membrane and shoving them back outside. The figure above is linked to a page at Helsinki university that discusses this type of preservative action in more detail.
Simple and elegant, and this seems to have been assumed to be the whole explanation for some time. But what happens to the benzoate ion when its hydrogen ion gets pumped away? Does it do anything?
Coming up next: Endocannibalism!
Don’t misunderstand – I like all kinds of foods made with eggs. Eggs are tasty. They’re handy. They’re nutritious, too. Their protein is so good they are the standard against which nutritionists have historically compared other food proteins. As a bonus, a medium-sized egg contains only one-eighth the cholesterol in a single ounce of human brain (and is much less likely to give you kuru).
However, could it be possible to come up with a more inconvenient packaging scheme? This thing was obviously designed by someone that hates us. “Let’s see, we’ll make it tasty and very nutritious. But just so people don’t think we like them, we’ll make it the consistency of snot, and package it by sealing it inside a specially-made, inedible brittle container so that you have to literally smash the thing open to get at the food, ensuring that the consumer* gets nasty goo all over his or her hands, or gets shards of the container mixed in with the food, or both. That’ll show the little jerks. And if that’s not enough, we’ll also have that container extruded out of a chicken’s butt.” (For some odd reason, as I write this, I’m picturing an Evil Santa Claus giving a presentation to the Evil Elves who are about to go off and implement this idea…”Sneezy, Drippy, and Runny – you three will head up the design committee…”)
They’re not screw flies or anything, but perhaps eggs can still count as an example of “irreducible grotesqueness”. (The picture, in case it isn’t obvious, is an egg separator. The image is linked to the site where you can buy them.)
This short rant has been brought to you by I’m-Making-Too-Many-Egg-Based-Meals-Lately Industries. That, and a second test to make sure I’ve got the DNS issues that I initially had resolved now. Can you all see this? I’d be thankful if everyone who was seeing this would post a quick “yeah, I see it” in the comments so that I can get on with the real posts again.
* Am I the only one who finds it insulting to be called a “consumer”, as though I were nothing more than a gaping mouth with a wallet? Am I sitting here mouth agape like a baby bird, waiting for a “supplier” to stroll by, grab some money out of my wallet, and cough up some “product” for me to “consume”? (I contend that I am not a “consumer” but a active participant in this economy, dagnabbit!)
(Tap Tap Tap) Is this thing on?…
Move is underway. Here’s a quick update / test.
On the way home (to Texas, that is, with a load of furniture from House v1.0 in Idaho) we adopted a co-dog. Now Cornelia isn’t the only official dog in the house.
Yeah, I know, pretty frivolous stuff. What do you want – this is mainly a test post. You guys ARE seeing this post, right? (Please comment and let me know). I’ve finally found and jumped through the hoops necessary to migrate the bigroom.org website over to the new host. It’s also running on the old server in House v1.0 on the DSL line as well, but this post isn’t getting put on it. If I’ve done everything correctly, hosting for bigroom.org should now be handled by Eskimo North. Just a few other minor tweaks and I’ll be set to return to House v1.0 and shut down the old server so I can move it down here to Texas.
I’ve gone from about 4400ft elevation down to about 250ft, but the plastic bottles of Mountain Dew® Wine seem to have positive pressure, so it would appear there is still some live yeast left in there and the priming sugar is slowly doing its job. I’m pretty sure the benzoic acid is what’s slowing down the activity so drastically, but it hasn’t killed it off yet.
I’ve also got a couple of entries in mind already for the next The Giants’ Shoulders blog carnival, and hopefully some more crazed brewing project news to offer sometime. And, of course, the promised post on why benzoic acid works. Stay tuned.