Friday, June 29, 2007

Caesar salad

My SO and I have loved Caesar salads for a long time, and thus many years ago we made our own home-made Caesar salad following Joy of Cooking's recipe. While the dressing is quite simple, we ran into a problem: it had too much raw garlic. As you may know (if you've read many of our other recipes), we're not ones to shy away from garlic, but raw garlic can be extremely sharp, and thus a few of our early batches of dressing were too sharp to thoroughly enjoy. However, by reducing the amount of raw garlic added, and replacing it with garlic that's been simmered in oil, we've been able to keep a strong garlic flavor without risking sharpness. If you've never had a homemade (or fancy restaurant) Caesar salad, the flavor (and lack of creamy white goo) may surprise you.

This recipe includes homemade croutons, which provide extra garlic for the dressing and are tastier than typical store-bought ones, but feel free to use pre-made ones if you're in a hurry (as the rest of the salad is quick and easy to make). Since we just had this for dinner a few days ago, it's this week's end-of-the-week recipe blogging post.

For the croutons:
6 cloves garlic, thinly sliced
3 tablespoons butter
4 tablespoons olive oil
5 cups of ~1/2" cubes of bread (we often use whole-wheat sandwich bread, just because we have it around, but a good hearty bread like ciabatta is best)
1/2 teaspoon kosher salt
1/4 teaspoon ground black pepper

For the dressing:
Reserved garlic from the croutons
1 medium clove garlic, finely minced or pressed with a garlic press
1/4 teaspoon ground black pepper
1 tablespoon fresh lemon juice
1 teaspoon Worcestershire sauce
2 teaspoons fish sauce (the Thai ingredient) or 2-4 mashed anchovies with a pinch of salt
1/2 cup extra virgin olive oil
2 whole eggs, raw or simmered for a minute or two (see notes)

For the salad:
Romaine lettuce (or whatever greens you'd like)
Grated, shredded, or shaved Parmesan or Pecorino Romano cheese

To make the croutons:
0. Preheat your oven to 350F.
1. Heat the olive oil and butter in a frying pan over medium heat.
2. Once the oil is hot, add the garlic and heat long enough for the garlic to start bubbling (the garlic should not brown). Remove from the heat and let sit for 10 minutes.
3. Strain the garlic from the oil, saving both the garlic and the oil. The oil will be used to season the croutons, and the garlic will be added to the dressing.
4. Put the bread cubes into a large bowl, sprinkle with salt and pepper, and pour the garlic oil over them. Toss to distribute the oil, salt, and pepper, and then put into a rimmed baking sheet large enough to hold all the bread in a single layer.
5. Bake for ~12-20 minutes at 350F, or until the bread is golden brown, stirring every 4 minutes.
6. Set aside until ready to serve.

To make the dressing:
1. Add the reserved garlic from the crouton making (mash it into a paste, if desired), raw garlic, pepper, lemon juice, Worcestershire sauce, and fish sauce or anchovies to a salad dressing shaker (or bowl) and mix well.
2. Add the olive oil and mix until emulsified. If you're using a salad dressing shaker you can add all the oil at once and then shake vigorously until well mixed; if you're using a bowl, add the olive oil in a slow, steady stream while you whisk constantly.
3. Add the eggs, and mix well.
4. Refrigerate until ready to use.

To assemble the salad:
1. Wash the lettuce or other greens, spin (or shake) them dry, and tear or cut into bite-sized pieces.
2. Put the greens into a bowl and top with dressing, cheese, and croutons.

Notes:

Aficionados of Caesar salads will note that fish sauce isn't a typical ingredient. We use it because we rarely have anchovies on hand, but we always have fish sauce. Since fish sauce is, well, fish flavored, adding a bit of it imparts the same fishy undertone that anchovies do. So, if you have anchovies on hand, by all means use them, but if you're out of anchovies feel free to use fish sauce.

Raw eggs are a standard addition to Caesar salad dressings, but they do have the potential to carry pathogens. One way to mitigate the danger of the raw eggs is to simmer them in water for a minute or two, but this does not remove all the risk. While we're willing to accept the risk of eating raw eggs, you may not be, in which case we'd advise using another recipe, as we know of no good substitution.

In a classic Caesar salad, the eggs are added to the salad separately from the dressing. This makes dressing the salad more tedious, however, and thus we prefer mixing the eggs directly into the dressing.

This makes about 1 cup of dressing. We find this is usually enough for four large (entree-sized) bowls of salad; ditto for the amount of croutons (unless you, like us, can't resist eating them, in which case this will make enough croutons for two large bowls of salad and a bit of snacking).

Reference:

Rombauer, I. S., M. R. Becker, and E. Becker. 1997. Joy of Cooking. Scribner, NY.

[Updated November 2007 to clarify the garlic cooking instructions and change where the salt and pepper were added to the croutons.]

Ordering glasses online

My SO and I just went in for our annual eye checkups, and it's finally time for both of us to replace our several-year-old glasses. As usual, after the checkup we were directed to the eyeglass sales area of the store, and a sales rep came out to help us pick out frames. We both tried on a number of frames, and selected a few to price out. The cheapest frame I had chosen was $200 after insurance, and the most expensive was more than $500 after insurance. Lenses would have cost about $100 extra. My SO's potential frames were in the same price range, but would have had even more expensive lenses. All told, we probably would have spent more than $1,000 buying new glasses at the optometrist.

Thankfully, we knew that we could find a better deal, as a while ago I found Glassy Eyes, a blog about ordering glasses online. While ordering glasses online is a bit harder than ordering them in person (you must enter your prescription manually, know your interpupillary distance1, and analyze the frame sizes to see how they'll fit on your face), the price difference was astounding: there are multiple websites where you can find quite decent looking glasses for less than $40 a pair, including lenses.

So, rather than spending $1,000 at our local optometrist, my SO and I just ordered a new pair of glasses for each of us from Optical4Less, spending less than $100 total. While I'm willing to pay for the extra service an optometrist provides, and the convenience of a local store, said conveniences are not worth a ten-fold increase in price.

If these glasses turn out to be good, I think we're going to go on a glasses-buying binge.

1 While you can measure interpupillary distance with a ruler, we did it using a binocular compound microscope with adjustable-width eyepieces.

Thursday, June 21, 2007

A few remodeling links

How to caulk around a shower - my SO and I used this as a guide for caulking our bathroom floor.

Suggested order for painting a house - A discussion board thread with a recommendation for the order of painting a house (and any room in it; we used this to guide our painting in the bathroom)

Installing interior moldings - While we have a detailed book on this topic (Finish Carpentry by Gary Katz), it was nice to have another illustrated source.

How To Install Baseboard Molding, Even On Crooked Walls - Tips to resolve a few common molding installation problems.

The Finish Carpenter's Manual by Jim Tolpin - A book with sample pages available via Google Books, one of which (page 104) just happened to succinctly summarize how to scribe baseboard molding. Based on the preview, this looks like a great book on finish carpentry.

Casing Problems - Drywall Not Flush With Jamb - Not that we're saying that this happened in our house (after all, our remodeling has gone so smoothly!1), but this is an illustrated example of how we would have dealt with drywall that ended up being proud of the door jamb if it had occurred.

This Old House video on installing crown molding - The text on the page is a bit more useful than the video, though it was nice to see someone actually installing it (rather than just reading about it)

1 And if you believe that, just go read some of the posts linked to here; then you can come and tell me if I'm being sarcastic or not.

Wednesday, June 20, 2007

A big day for Radagast and SO

You may recall that my SO and I have been remodeling our house; the primary motivation for this was finding water damage (and resultant mold growth) in both bathrooms when we bought the place.

While our bathroom remodeling predates this blog, we've written about a lot of it here. To summarize, we ripped everything out to the studs, replaced all the plumbing (both supply and waste), installed new windows, redid the drywall, painted, and spent forever working on the floor. While both bathrooms were ripped out to the studs way back when, we've focused most of our energy on trying to finish the master bathroom, which (embarrassingly) we've hoped to do since 2004.

It is thus with great excitement that I'm able to report a major accomplishment: we now have a functioning toilet, sink, and shower in our master bathroom. While the room is not entirely finished yet (we need to finish the moldings, paint the door, and do a few other small tasks), everything that counts is in.

Yippee!

Now I just need to come up with more excuses to go in there and admire it.

Monday, June 18, 2007

Basic cheese sauce

Some of my fondest childhood memories are eating my mom's steamed cauliflower slathered with cheese sauce after returning from trips1. What follows is the Radagast and SO household standard cheese sauce recipe; while this isn't the fanciest cheese sauce, it's easy to make, reminds me of my mom's, and tastes, well, cheesy. Since we had cauliflower with cheese sauce last week, this is this week's end-of-the-week recipe blogging post.

1/4 cup (4 tablespoons) unsalted butter
1/4 cup (4 tablespoons) flour
2 cups milk
2 cups grated cheddar cheese (we use medium cheddar)
1/2 teaspoon kosher salt
1/4 teaspoon ground black pepper

0. Heat the milk in the microwave (or in a small saucepan over medium heat), but do not bring it to a boil.
1. Melt the butter in a non-stick saucepan over medium-high heat.
2. Add the flour, and, stirring constantly, cook until the flour browns slightly (probably around 3 minutes).
3. Remove the pan from the heat and let cool, stirring frequently, until the flour mixture stops bubbling.
4. Add the warmed milk to the flour mixture, return to the heat, and whisk constantly until smooth.
5. Cook, whisking frequently, until the sauce is somewhat thickened (probably about 5 minutes).
6. Add the cheese (adding it in two batches helps keep it from forming a giant, slow-to-dissolve blob) and stir until all the cheese is melted.
7. Add the black pepper and salt; taste, and adjust the seasonings to your liking.

Notes:

If you like nutmeg (which Radagast doesn't), a pinch or two might compliment the sauce's flavor.

This sauce should be served warm, as it thickens when it cools. A skin may form on the surface of the sauce if it sits for a while at room temperature; just stir this skin back into the sauce and it will be fine. If the mixture begins to thicken too much before you're ready to eat it, simply re-heat it on the stove (or in the microwave) briefly, stirring frequently.

1 I still love cheese sauce on cauliflower, though these days I typically use roasted cauliflower as the base, not steamed.

Saturday, June 16, 2007

Roger Waters live


Originally uploaded by DaigoOliva

[Spoiler warning: This post includes details about Roger Waters' 2007 tour]

My SO and I don't go to many concerts, but this week we went to see Roger Waters (of Pink Floyd fame). The tour advertised that he would be playing the entirety of Dark Side of the Moon, but he also played a great assortment of his other work1 (list from here):
  • In The Flesh
  • Mother
  • Set The Controls For The Heart Of The Sun
  • Shine On You Crazy Diamond
  • Have A Cigar
  • Wish You Were Here
  • Southampton Dock,
  • Fletcher Memorial Home
  • Perfect Sense Parts 1 & 2
  • Leaving Beirut
  • Sheep
  • The Happiest Days of Our Lives
  • Another Brick In The Wall Pt. 2
  • Vera
  • Bring The Boys Back Home
  • Comfortably Numb
While our seats weren't terribly close to the stage, the venue had continuous video footage broadcast on large screens. Much of this video footage focused on the guitarists' hands, which I was appreciative of thanks to my newfound hobby of playing the guitar2.

As one might guess, Roger has little love for George W. Bush, and thus included many jabs at him. His new song Leaving Beirut had a graphic-novel-style background including the lyrics, which included this bit:


Roger Waters_Leaving Beirut - Oh George! Oh George!
Originally uploaded by Garry'


Oh George! Oh George!
Originally uploaded by Garry'

He also had a floating pig covered in graffiti:


A Pig never lies
Originally uploaded by Ronaniversario

While our pig didn't look exactly like the one pictured above (after browsing Flickr it appears that a new pig is made for each show), the writing on our pig included such statements as "Torture shames us all," "All religions divide," "Impeach Bush," "What an asshole [with an arrow pointing to "Bush"]," "Fear builds walls," and "Habeas corpus matters."

My favorite was the addition of a quote from Bush in the background visuals for The Fletcher Memorial Home:


Fletcher Memorial Home
Originally uploaded by EddieBerman

Ignoring all the traffic getting to and from the concert, it was a great evening of prog rock. Up next: Genesis.

1 I was probably one of the few fans in the audience who was sad that most of his solo work was left out.
2 Methinks it will be a very, very long time before I'm able to come anywhere close to playing songs like them.

[Note: All images in this post are Creative Commons licensed.]

Wednesday, June 13, 2007

Big news for SC

Semantic Compositions has just posted some big news: he's starting his own company! This sounds like a great decision for him; I wish him all the best.

And, if he ever needs a biologist to consult for him, I'll be happy to give him my special friends-only discount rate (based on, of course, the rates his prior employer charges).

A little fluff

My SO and I are busy working on the house this week1, so here are a few resources to entertain you:

High-speed pictures of milk dropping into coffee (via BoingBoing)

Video of flight traffic patterns over the US (higher-quality here) (via PZ)2

Demonstration of the power of CSS (via Semantic Compositions)

1 It's amazing how long seemingly simple tasks can take when one is remodeling. For instance, I just spent most of today painting (and priming, and patching) a door frame. On HGTV things like that take about 5 seconds (if they even show it).
2 Moral of the story: If you don't want to have planes flying over you all day, go live in the Pacific northwest.

Sunday, June 10, 2007

Roasted cauliflower

A few years ago my SO came across this recipe for roasting cauliflower. We posted a link to it way back when, and since then it's been one of our most-cooked recipes. However, the original recipe is written rather vaguely, and thus we're re-posting it here with more detailed instructions. This is also one of this week's end-of-the-week recipe blogging posts, as we just made this again last week.

And, to reiterate what we've said before, this is quite possibly the world's best method of cooking cauliflower; if you haven't tried it yet, you're missing out.

1 head cauliflower, rinsed (approximately 2 pounds untrimmed; ~1 3/4 pounds trimmed)
2 tablespoons olive oil
1/2 teaspoon kosher salt
1/4 teaspoon ground black pepper

0. Preheat your oven to 475F.
1. Remove the leaves and any bad spots from the cauliflower.
2. Cut the head of cauliflower into florets. We prefer large-ish florets (maybe 1 1/2 inches in diameter), though the size doesn't matter much. You can also chop the stem and include that as well (we cut the stem into ~1/4" thick slices).
3. Put the florets and stem slices in a roasting pan large enough to hold them in a single layer, and then sprinkle with the olive oil, salt, and pepper. Stir to mix.
4. Roast for 35 minutes, or until there are numerous small browned/blackened bits in the pan, and all the florets are well browned in spots (they'll appear to be almost burned). Stir every 10 minutes while baking, using a wooden spoon/spatula to scrape the stuck pieces off the bottom.
5. Serve immediately.

Notes:

This is best immediately after it comes out of the oven; it tends to get a bit mushy and lose some of its excellent flavor once it has cooled. The little nearly-burned bits in the bottom of the pan are full of flavor; we enjoy scraping them out of the pan and adding them to our plates.

This makes enough to serve as the primary component of a meal for two; it'd probably make enough for a side dish for four, though we rarely serve it as a side dish. This is perfectly delicious plain, but can be served with a cheese sauce if desired.

This recipe scales well, so feel free to vary the amount of cauliflower (as long as the cauliflower fits in a single layer in your roasting pan).

Reference:

Weide, Stephanie Vander. 2004. "Blue Plate Special: Cauliflower and Crabs". Grub Report, December 12, 2004. http://www.grubreport.com/blueplatespecial/caulicrabs.html. Accessed 2005.

Peanut butter chocolate chip cookies

My SO and I love moist, chewy cookies. We were thus ecstatic when we found this recipe, which makes huge cookies (they're about 3 1/2" in diameter and about 3/4" thick) that stay moist and chewy for days after cooking. Since we've gotten rave reviews of these from friends recently, they're this week's first end-of-the-week recipe blogging post.

1/2 cup (1 stick) butter, softened
1/2 cup crunchy peanut butter
1/2 cup sugar
1 cup brown sugar, packed
2 large eggs
2 tablespoons light corn syrup
2 tablespoons milk
2 teaspoons vanilla extract
1 1/2 cups flour
1 teaspoon baking soda
1/2 teaspoon salt
2 cups semi-sweet chocolate chips

0. Soften the butter (by letting it sit out at room temperature for a while), and preheat your oven to 375F.
1. Cream the butter, peanut butter, sugar, and brown sugar together in a large bowl (we use our stand mixer) until it is as smooth as it will get with the peanut chunks in it.
2. Add the eggs one at a time, mixing after each addition.
3. Mix in the corn syrup, milk, and vanilla.
4. Mix the flour, baking soda, baking powder, and salt together in a bowl.
5. Add the flour mixture to the wet ingredients, mixing until well combined.
6. Add the chocolate chips, mixing until just combined.
7. Measure out 1/4 cup chunks of dough and place onto a cookie sheet. We use a silicone cookie sheet liner to make removing the cookies easier after baking; you may want to grease your cookie sheets if you don't have a liner.
8. Bake for 13 minutes at 375F, or until the cookies are turning brown at the edges. They may appear slightly underbaked; this is OK, as they'll continue cooking a bit outside the oven (though test various cooking times to see what best suits your oven and tastes).
9. Let rest on the cookie sheet (out of the oven) for a minute or so, then remove the cookies to a rack to cool completely.

Notes:

If you want smoother cookies, use non-chunky peanut butter. We use the standard variety peanut butter that's been salted and sugared, but this is almost certainly flexible.

Based on a recipe by Kathy Bliesner from Allrecipes.com.

Bliesner, Kathy. "Chewy Peanut Butter Chocolate Chip Cookies" http://allrecipes.com/Recipe/Chewy-Peanut-Butter-Chocolate-Chip-Cookies/Detail.aspx. Accessed April 2003.

Thursday, June 07, 2007

Installing Ubuntu 7.04 - Feisty Fawn

Ubuntu desktop with application menu open

Today I finally got around to installing the latest version of Ubuntu (7.04 - Feisty Fawn). The installation was very easy, especially since my original partition plan included a blank 12 GB partition to hold a new version of Ubuntu. All I had to do was download the 7.04 live CD, boot from it, and then install Ubuntu 7.04 to the blank partition I'd created way back when1.

The look and feel of this version (7.04 - Feisty Fawn) is much the same as the prior version (6.06 - Dapper Drake), so everything I'd learned about 6.06 transferred right over to the newest version. However, there are two major improvements I've already noticed:
  • Restricted drivers manger - This little menu item (System -> Administration -> Restricted Drivers Manager) allowed me to install my nVidia video card's driver in less than a minute. In the old version (6.06) I'd had to go and find the package manually, and then fiddle with a few settings. In Feisty Fawn all I had to do was click one button and it was installed.
  • Multimedia codec finder - Whenever I click on a media type to play it, Ubuntu now automatically checks to make sure that it has the proper codec installed. If it doesn't have the right codec installed, it searches the repositories, finds the proper package, and asks if I want to download it. I've now been able to play mp3s, quicktime videos, and flash videos all within 30 seconds of clicking on them.
The new version also includes updated versions of all the major software, so I'm currently enjoying Firefox 2, Gaim 2, and all the other little package improvements. Since I've just gotten done customizing my new install, I thought I'd share a few of the changes I made:
  • I installed gaim-guifications, a package that lets Gaim pop up notification windows whenever I have an incoming message (much like Google Talk, Outlook, and other programs do in Windows). After installing the package ("gaim-guifications"), I had to enable it in the "plugins" menu of Gaim.
  • I installed my usual assortment of FireFox extensions, including Adblock Plus (which blocks ads), Adblock Filterset.G updater (which automatically updates Adblock's list of ads to block), Flashblock (which automatically blocks all flash applications from starting, preventing many websites from being annoying), Tab Mix Plus (which, among other things, allows you to force all new windows to open in new tabs), and Video Downloader (whose purpose should be fairly intuitive).
    • I also configured FireFox so that it would allow smaller tabs, meaning that I won't have to scroll left and right to see all my tabs if I open too many. To do this I went to "about:config" in the browser window and then edited the "browser.tabs.tabMinWidth" value to be 20 (the default was 100; installing the Tab Mix Plus extension meant I had to change the "extensions.tabmix.minWidth" value as well).
  • Installed cups-pdf, a package that creates a PDF printer (so I can convert anything I want into a PDF simply by printing it). I followed the instructions here, but essentially all you have to do is install the package "cups-pdf" and then add a new printer (selecting the PDF printer, and then choosing "generic color postscript" as the options). All created PDFs go into the "PDF" directory of your home directory; sym-link this to wherever you want them to go.
  • Installed my image resizing script; this required me to install ImageMagick (via the "imagemagick" package), but otherwise was simple.
If you want to learn more about Ubuntu, head over to Ubuntu.com, or go look at my illustrated tour of Ubuntu (which was based on 6.06, but everything looks virtually identical in the newest version). I've enjoyed using Ubuntu for the past year; it's been my default home operating system for the past year, and I plan on using it for much of my work starting this fall2.

1 The only problem I've run into so far was that Ubuntu set my maximum resolution to be 1024x768. To fix this I had to manually edit my X configuration file ("gksudo gedit /etc/X11/xorg.conf") and add the option to use a 1280x1024 resolution (by adding that resolution in the "screen" section of the file, next to all the other resolutions listed).
2 In fact, I just reduced the size of my Windows partition so that I'd have more space for files in Ubuntu.

In the news

Looks like I was right; CNN has finally decided that 100% fruit juice won't make your kids fat after all.

Carbon dating of chicken remains in South America has provided evidence that Polynesians sailed to the Americas at least a hundred years before the Spanish did. Chickens are not native to the Americas, yet the chicken remains date to AD 1321 to 1407.

And, don't expect widespread Mad Cow testing to occur anytime soon in the US; the Bush administration is fighting to prevent a company from testing all their cows for the disease:
The Bush administration said Tuesday it will fight to keep meatpackers from testing all their animals for mad cow disease .

The Agriculture Department tests less than 1 percent of slaughtered cows for the disease, which can be fatal to humans who eat tainted beef. But Kansas-based Creekstone Farms Premium Beef wants to test all of its cows.

Larger meat companies feared that move because, if Creekstone tested its meat and advertised it as safe, they might have to perform the expensive test, too.

The Agriculture Department regulates the test and argued that widespread testing could lead to a false positive that would harm the meat industry.

A federal judge ruled in March that such tests must be allowed. U.S. District Judge James Robertson noted that Creekstone sought to use the same test the government relies on and said the government didn't have the authority to restrict it.

The ruling was to take effect June 1, but the Agriculture Department said Tuesday it would appeal -- effectively delaying the testing until the court challenge plays out.

Wednesday, June 06, 2007

Fungi that live off radiation

Some of you may have already read this on BoingBoing or /., but if you haven't, here's the big news: there is now evidence that fungi may be able to obtain metabolic energy from ionizing radiation. By ionizing radiation I don't mean that stuff that we see as light, and that plants use to obtian energy through photosynthesis; I mean nuclear radiation. As in, the stuff that kills you (e.g., what Caesium 137 emits). This is cool.

The study (Dadachova et al. 2007) was published in PLoS One, meaning that it's completely open access. So, while I'll summarize a few of the biological details here, if you want all the nitty gritty, head over there and read away.

The researchers started their search by noticing that fungi growing in radiation-intense environments (e.g., around the Chernobyl reactor) tended to have extremely high levels of melanin in their cells (yes, the same type of pigment that humans have in their skin). While this melanin has been hypothesized to function in a protective role (by absorbing radiation and dealing with the free radicals that are produced), the researchers wondered if the fungi might be able to use melanin, and the high-energy electrons it produces, for more than just protection.

To start, Dadachova et al. did a number of biochemical experiments: they showed that the fungal species they were working with (Cryptococcocus neoformans, Cladosporium sphaerospermum, and Wangiella dermatitidis) expressed melanin, analyzed the fungal melanin via HPLC and ESR, and determined that melanin exposed to radiation could speed up other oxidation reduction reactions (i.e, that radiation could affect the metabolic reactions of the cell). To show that melanin could affect oxidation reduction reactions, Dadachova et al. isolated melanin from fungal cells, mixed it with NADH and ferricyanide, and then showed that the rate of the NADH\ferricyanide oxidation reduction reaction increased when the solution was exposed to radiation. While Dadachova et al. state that the mechanism by which radiation energy is absorbed by melanin and transfered to biochemical reactions is unknown, based on their work it sounds like what might be going on is that melanin is eventually reducing NAD to NADH. This would be elegantly simple metabolically, as one of the primary products of the Krebs cycle (i.e., the cycle in fungi that metabolizes sugar) is NADH; NADH from the Krebs cycle is then used to power the electron transport chain, which ends up producing ATP. So, if melanin was reducing NAD to NADH using energy from radiation, it would be extremely simple to turn that NADH into usable ATP1.

Dadachova et al. were able to obtain a mutant strain of C. neoformans [Lac(-)] that was unable to produce melanin. Thus, to test the hypothesis that melanin is the pigment that absorbs radiation, and that this radiation absorption provides useful energy, Dadachova et al. grew both melanin-producing and non-melanin-producing C. neoformans in either irradiated or non-irradiated conditions2. The results are below:

figure 6 from the journal article
Growth of normal C. neoformans (left) or non-melanin-producing C. neoformans (right) in either irradiated or non-irradiated conditions. Modified from figure 6 of Dadachova et al. (2007).

This is exactly what we'd expect to see if melanin was providing energy for growth: the melanin-producing fungi grew faster when exposed to radiation (the red bar in the left graph), but when the fungi were unable to produce melanin, there was not much of a difference between the irradiated and non-irradiated fungal growth (right graph).

Dadachova et al. were able to do essentially the same experiment with another species of fungus, W. dermatitidis, which they were also able to obtain a non-melanin-producing mutant of. Again, the results show that the fungi grew better when exposed to radiation:

figure 8 from the journal article
Growth of normal W. dermatitidis (left) or non-melanin-producing W. dermatitidis (right) in either irradiated or non-irradiated conditions. Modified from figure 8 of Dadachova et al. (2007).

One thing to note here is that radiation does not appear to be required for these fungi to live; the mutant strains that don't produce melanin (and thus presumably cannot use this energy-gathering pathway) still grew, and the fungi that did produce melanin were able to grow even in the absence of extra radiation. Thus, this mechanism is not directly analogous to plant photosynthesis (as photosynthesis is typically the sole mechanism by which plants obtain energy, while radiation is not the sole energy source for these fungi).

When we think of organisms growing based on electromagnetic radiation, we think of plants, which get energy from light and carbon from carbon dioxide. Plants use the energy they get from light to take carbon dioxide from the atmosphere and assemble it into sugars (which nicely store the energy they've captured from light in a chemical form). Plants are therefore known as photoautotrophs (photo: getting energy from light; autotroph: obtaining carbon from an inorganic source, such as carbon dioxide). Animals, along with fungi and many other non-photosynthesizers, typically get their energy from organic molecules (i.e, sugar, fat, protein), and their carbon from those same organic molecules. Thus, animals and fungi are known as chemoheterotrophs.

A question with these radiation-using fungi follows: are these fungi fixing carbon dioxide from the atmosphere, like plants, or are they getting carbon from organic molecules, like most other fungi do? In other words, are these fungi heterotrophs (like most other fungi) or autotrophs (like plants)? To partially test this, the researchers added acetate (an organic form of carbon) to the fungal growth medium, and labeled that acetate with carbon-14. They then exposed both the normal fungi and the non-melanin-producing fungi to radiation, and observed that the normal fungi incorporated significantly more carbon-14-labeled acetate into their cells when they were exposed to radiation. Since the fungi were absorbing the acetate at higher rates when exposed to radiation, it seems as though the fungi are still using heterotrophic mechanisms of carbon uptake (i.e., they're not autotrophs, though note that they didn't directly test for absorption of carbon dioxide).

So, as Dadachova et al. say in their discussion,
[W]e cautiously suggest that the ability of melanin to capture electromagnetic radiation combined with its remarkable oxidation-reduction properties may confer upon melanotic organisms the ability to harness radiation for metabolic energy. The enhanced growth of melanotic fungi in conditions of radiation fluxes suggests the need for additional investigation to ascertain the mechanism for this effect.
Looks like it's time to go add another line to that "sources of energy for growth" slide in my lecture.

1 Note that this is pure speculation on my part, and I'm most certainly not a biochemist.
2 For the irradiated growth conditions, Dadachova et al. exposed the fungi "to a radiation field of 0.05 mGy/hr created by 188Re/188W isotope generator".

Dadachova E., RA Bryan, X Huang, T Moadel, AD Schweitzer, P Aisen, JD Nosanchuk, and A Casadevall. 2007. Ionizing Radiation Changes the Electronic Properties of Melanin and Enhances the Growth of Melanized Fungi. PLoS ONE 2(5): e457. doi:10.1371/journal.pone.0000457. Full-text.

Monday, June 04, 2007

Country-style pork ribs with a spice rub

Regular readers will note that, as a general rule, my SO and I rarely cook large hunks of meat for meals. Our primary exceptions to this are pieces of good fish, roasted whole poultry, and country-style pork ribs. Country-style pork ribs are thick cuts of meat (2"x2"x8" or so) that are marbled with extensive amounts of fat (see pictures on Google). Their high fat content makes them an excellent choice for long, slow cooking; after a few hours in the oven they're exceptionally moist and falling-off-the-bone tender.

For a long time we made Joy of Cooking's country-style pork rib recipe, which calls for cooking the ribs in a mixture of barbecue sauce and orange juice for three hours. While they're excellent, they end up very sweet, and so a few months ago my SO and I started hunting for a less sweet (and more spicy) recipe for pork ribs. We found this recipe for a dry spice rub, which is a mix of hot (cayenne, mustard, and black pepper) and flavorful (paprika, cumin, and garlic) spices. We quickly fell in love with these ribs, and since then we've made them for multiple folks (including my mom), and everyone who has tasted them has raved about them (translation: they're mom-approved!). Since this is our new standard method of cooking country-style pork ribs, they're this week's end-of-the-week recipe blogging post.

Note: this recipe must be started the night before you want to eat it, and then takes three hours to cook on the day it's made, so plan ahead. That said, this is an extremely easy recipe to make: it probably takes less than 20 minutes total preparation time across both days, and needs absolutely no tending once it's been put in the oven.

5 pounds country-style pork ribs, rinsed and patted dry
5 garlic cloves, peeled and finely minced or pressed with a garlic press
1/4 cup paprika
2 tablespoons brown sugar
1 1/2 tablespoons black pepper
1 tablespoon plus 1 teaspoon kosher salt
1 1/2 teaspoon cayenne pepper
1 1/2 teaspoon dry mustard
1 1/2 teaspoon ground cumin

The day before you eat the ribs:
1. Mix the spices together in a bowl.
2. Rub the spices and minced garlic over the meat, attempting to cover all the sides. We do this after we've lined up the ribs in a 9x13" glass baking dish, but you could do it before. Your hands will get covered in spices; they wash off easily.
3. Arrange the ribs in a baking dish, tightly cover with foil, and refrigerate overnight.

The day you eat the ribs:
0. Preheat your oven to 325F.
1. Remove the pan from the fridge and pour in 1/2 cup water.
2. Re-cover the pan with foil, and bake for 2 1/2 hours at 325F.
3. Remove the ribs from the oven and let cool for ~10 minutes before serving.

Notes:

Normally we eat these right out of the oven, but you can also briefly cook the ribs on a barbecue after removing them from the oven. We tried this last week, and it crisps the fat still left on the meat, making the fat extremely tasty (normally we simply remove the fat from the meat as we eat it).

There will probably be a lot of fat in the pan after the ribs are baked; this is perfectly normal. What you may not notice, however, is that hidden underneath all that fat is a layer of meat drippings and spices. This juicy goodness can be turned into a sauce by pouring all the liquid contents of the pan into a fat separator (a glass or clear measuring cup would also work), letting it sit for a minute so that the fat separates out, removing the fat1, and then putting the remaining liquid into a small pot or saucepan. Simmer the drippings for a few minutes to slightly thicken them, and then serve alongside the meat as a dipping sauce. Creating this sauce is entirely optional; the ribs are delicious without it.

Country-style pork ribs can come either boneless or bone-in; it really doesn't matter which you get, as the meat falls off the bone after cooking anyway.

1 If you're using a glass or clear measuring cup, you should be able to simply spoon off most of the fat.

This is based on a recipe from desurfer at ratebeer.com.

Desurfer. "Hot & Spicy Country-Style Ribs" http://www.ratebeer.com/Recipe.asp?RecipeID=102. Accessed sometime in 2007.

[Update: Commenter Mikey-Mike reports that Desurfer likely got this recipe from Steven Raichlen's book "The Barbeque Bible."]