Thursday, July 31, 2008

You Say Xitomatl, I Say Tomatillo

Tonight I cooked tomatillos for the first time.

I suspect that most of my regular readership knows at least vaguely what a tomatillo, also known as a husk tomato, is, but just in case, these are tomatillos:

Physalis philadelphica

They're green and tart, and from what I can tell, their primary use is making salsa verde.

They're also great for confusing cashiers at the grocery store. Apparently, in New Brunswick tomatillos are purchased so infrequently that they were not in the computer system; a manager had to trek to the produce aisle to find the price.

It's too bad, because they're absolutely delicious. I took a bite of one before cooking, out of curiosity, and found it very pleasant. It was tart, yes, but flavorful and not overwhelming. It didn't make my face screw up the way it does when I lick a lemon; it was more like the pleasant tartness of a granny smith apple (which it strongly resembled visually) without any of the sweetness.

The dish I was making was not salsa verde, but it may as well have been. It was basically a souped up version of salsa verde, with lots of pureed corn, peas for extra green color, and for no discernible reason, canned green chilies. (That's what was in the recipe, and I like to follow recipes one time through before I fix them up.) Next time I make it, no cans necessary -- the jalepeños, for some reason, are thriving on our balcony and we should have a nice harvest starting soon. (It will add some heat, too -- the soup could use a little more hot pepper.) I can say with some satisfaction, however, that I used home-made veggie broth for the first time, with outstanding results.

Anyway, back to the tomatillo.

Tomatillos are in the nightshade family, although they are in a different genus from tomatoes. An interesting fact from Wikipedia is that tomatillos are self-incompatible; that is, you need at least two tomatillo plants to get any fruit. Whole Foods, meanwhile, indicates that they can be used to tenderize meat, probably due to their acidic content since it doesn't mention anything about our friends the enzymes.

According to Purdue, evidence of tomatillos has been found at the site of Tehuacán in Mexico, although they give a date range of 900 BCE to 1542 CE, which is not terribly helpful. (A lot can happen in 2100 years!) They do add that in pre-conquistador Mexico, the tomatillo was actually preferred over the tomato. (I would have to guess that their European visitors did not share this opinion, because we do not eat spaghetti and meatballs in salsa verde.) There was also, apparently, a lot of confusion about exactly which fruits were which, because Aztec words got a little mixed up by the Europeans.

GourmetSleuth, however, seems pretty sure that the domesticated tomatillo dates back to at least 800 BCE. They also have information that's a bit easier to read about the whole tomato-tomatillo-tomatl-xitomatl-miltomatl controvery. (Dang, now I wish I spoke Nahuatl. Apparently "tomatl" means approximately "round and plump", so that's a word I can get behind! Also, these are the same folks who gave us chocolate.) They also agree with Whole Foods that tomatillos freeze well but should be frozen whole.

So there you have it, the tomatillo in a nutshell. Or in a tomatillo husk, as the case may be.

The moral of the story: go buy some tomatillos and eat them, cook them, make salsa verde, confuse cashiers. I think they'd probably make an interesting margarita, too. Too bad I cooked all the ones I got today.

Tuesday, July 29, 2008

What, Me Worry?

John Tierney's column today, "10 Things to Scratch from Your Worry List" does our planet a considerable disservice.

OK, yes, it's true we don't need to worry about sharks (we never did), and local produce may not be all its cracked up to be. (Eating in season is still best, but it's more complicated.)

But what bothers me about this column is #5, "Evil Plastic Bags."
5. Evil plastic bags. Take it from the Environmental Protection Agency : paper bags are not better for the environment than plastic bags. If anything, the evidence from life-cycle analyses favors plastic bags. They require much less energy — and greenhouse emissions — to manufacture, ship and recycle. They generate less air and water pollution. And they take up much less space in landfills.
It's as though he's being willfully ignorant -- for if you follow the link to the EPA page, you know what they recommend? Bring your own bag! (Don't believe me? Click the link.) While plastic may require less space and less energy, they are also made from petroleum, which unlike trees, does not spontaneous grow from the ground.

In short, the evidence only marginally favors plastic bags in my opinion, and overwhelmingly favors the option of cotton canvas tote bag instead. Or reuse your plastic bags, if you can; I find that mine tend to rip well before the eleventh reuse, which is the point at which you have "broken even" by some reckoning. My bags of choice for regular grocery shopping are a combination of little green Stop n Shop bags and two long-handled canvas tote bags. (Long handles are good for slinging over shoulders.) If I was in the market for another bag, I might get this one. It's pretty! I keep extras in the car; I have a large canvas bag that can hold three six-packs of bottled beer (tested yesterday) among others.

Bring your own bags; then you don't have to worry about plastic bags or paper bags. And your groceries will taste better.*

*Note: groceries may not actually taste better.

Thursday, July 17, 2008

In Which I Am Perplexed

I am trying to imagine the contents of this book.


Notice the "Fact & Fiction" tag at the bottom right corner. Are there rampant fictions being spread right now about goat cheese? Have the cow cheese makers started telling nasty lies about goat cheeses, like goat cheese is actually made from baby goats? Is the moon not, in fact, a giant Crottin de Chavignol? Is goat cheese likely to kill you tomorrow?

Amazon is less than helpful. There are no reviews, no comments, no "See Inside This Book!", nothing.

The face of the goat on the cover is inscrutable. She is contemplating cheese; is she also contemplating the laughing goat? There are no "thought bubbles" connecting the two; perhaps he is a figment of her imagination. (And no, there is no particular reason I chose those genders for the goats; I just needed a handy way to distinguish them, and the pensive expression the brown goat suggests that she is thinking about where her milk is going.)

In short, what is going on here? If anyone out there has read this book, please tell me. I love goat cheese and I don't want to give it up because it might make me go insane or something. Thanks!

Tuesday, July 15, 2008

Chocolate-Covered Enzymes

Flipping through bridal magazines, you see many cakes. A majority of them, at least the über-fancy ones, are covered in fondant. Fondant (for those of you not shopping for pastry at the moment) is what makes cakes look like this:

It's a cake!

A cake frosted with buttercream, on the other hand, looks more like this:

Raspberry delight!

Both cakes look lovely, but notice how the top cake is so smooth and sculptural, while the bottom one (which in my opinion looks more delicious anyway) is a little rougher; there are little air bubbles and minor imperfections along the sides, the lines aren't quite perfect.

"What the heck does this have to do with science? I didn't come to this site to read about fondant vs. buttercream! I demand an explanation!"

Let's start out just talking about fondant. Fondant is a heavy paste which, at its most basic, is made with just water, sugar, a little food coloring, and a skilled hand. (A candy thermometer helps, and there are many variations using different sugar ingredients.) If you accidentally jolt the bowl while it's cooling, the sugar will come out of solution quickly and in large crystals; presto, rock candy!

However, by mixing the water and sugar together at a high temperature and then cooling it very gently, stirring violently at the very end, the supersaturated solution forms very tiny crystals that look as smooth as a lake on a calm day. You can use this paste to decorate cakes in myriad ways -- a quick Google images search for fondant cakes will give you an idea of just how many! You can sculpt with it. You can cut it and shape it. And, for all intents and purposes, you can even eat it. (Although not that many people do.)

Now, if you made fondant from scratch, you would likely just use sucrose -- that is, ordinary table sugar.

And if you cut that piece of fondant into squares and dipped them into chocolate, you would have this:
Minty!

"But wait! The inside of an After Eight mint is so creamy and soft! There's no way it could be the same as that stiff piece of fondant covering the cake up there!"

Ah. Yes. You have a point.

And that is where the enzymes come in. Invertase is a naturally-occurring enzyme produced by some bacteria as well as some animals that breaks down sucrose into its component sugars, glucose and fructose, which is sometimes known as inverted sugar syrup. (The reason for "invert" is interesting but I can't explain it well; read about it here.)

In the production of After Eight mints, a small amount of invertase is added to the minty fondant just before it is coated with chocolate. The enzyme doesn't begin to work immediately, so the chocolate can cool around the fondant before it begins to "cure". The smaller, more soluble molecules of glucose and fructose go into solution more readily and disolve in the small amount of water contained in the fondant; it isn't enough to create a runny liquid, but it's enough that when you bite into an After Eight (or any other fondant-filled treat) the texture is creamy and viscous and not a stiff paste.

Mmm, enzymes. What can't they do?

PS: On a totally unrelated note, we just watched the first segment of Dr. Horrible's Sing-Along Blog. Hilarious! So much fun! Go watch while you can, it's gone on Sunday.

Monday, July 14, 2008

Dr. Horrible

Speaking of fireflies...

So... normally I don't like to promote stuff or whathaveyou, there isn't any advertising on my blog... except for this!

Because: 1) science fiction is almost as good as science facts; 2) Neil Patrick Harris; 3)NATHAN FILLION; 4) it has the word "blog" in it, so it's relevant! 5) Oh, and did I mention Joss Whedon? Him too.

Watch it and stuff!

More real posts later.

Wednesday, July 9, 2008

Better Know an Insect: Femme Fatale Fireflies

Last night Dustin and I took an evening stroll through the park. It was a lovely, warm evening, with robins singing from the treetops and a slight breeze rustling the grass. And, of course, there were fireflies, lighting up the summer night with their romantic display, a visual analog to a bird's song.

Males, seeking females, blink their message in code, while females sit and wait on the ground for the right guy to come along. When she sees him, she blinks back until he finds her, and that's where baby fireflies come from. Aww.


Unless she's a hungry female of the genus Photuris, that is.

After Photuris females have mated, they don't need to mate again. But why waste a perfectly good signaling device? Instead, the Photuris females signal back to males of another species, Photinus, luring them in and catching them for dinner. Delicious!


But he's not just a tasty meal to help her lay eggs. It turns out that Photinus males produce a chemical that protects them from attacks by spiders and other arthropod predators. By eating Photinus males, the Photuris female acquires this armor and is herself protected from attack.

So, the next time you're out for an evening stroll in July, consider the drama playing out before you. There are dangerous femme fatales everywhere you look.

Read more about it on this page from Cornell.

Monday, July 7, 2008

Mater Familias

This article ran a couple of weeks ago.

Albanian Custom Fades: Woman as Family Man

I find everything about it interesting. A woman cannot head a household, but it's acceptable to change her gender and live her life as a man, and head a household. It is an interesting view of gender perception. While I'm glad that greater equality is coming to Albanian women, it's also a little bit sad that such an interesting cultural tradition (respected by both Christians and Muslims alike) is going to fade away within the next twenty years or so.

I don't know what else to say... any thoughts from the peanut gallery?

Saturday, July 5, 2008

DIY Dairy

In the spirit of reducing packaging from foods (is seltzer a food? maybe in Hollywood?) that I love, consider the yogurt maker.

"But dairy products were not meant to be made at home!" you might think. "They are frequently complicated, sometimes involve caves, and are generally not DIY projects!" Ah, but that is not always true. Yogurt is actually incredibly easy to make at home; technically, you don't even need a yogurt maker, but having one can greatly improve the reliability of your results. (And as a scientist, I am always in favor of reproducible results.)

Yogurt is delicious but also tends to arrive in non-recyclable plastic containers, creating even more guilt than recyclable seltzer bottles. (Yes, in some places you can recycle plastic #5, but for whatever reason, those places don't include New Jersey.) It also tends to come in fairly standard flavors, like peach and blueberry. Making yogurt at home allows you to create your own flavors. If I get a yogurt maker at some point in my life, I might start with herbal or spiced yogurts (lavender? thyme? cumin?), maybe play with extracts... cherry-almond is one of my favorite combinations, so a little almond extract (or even almond milk?) might be a tasty addition. We'll see how it goes.

Friday, July 4, 2008

July 4, 1776

WHEN IN the Course of human events, it becomes necessary for one people to dissolve the political bands which have connected them with another, and to assume among the powers of the earth, the separate and equal station to which the Laws of Nature and of Nature's God entitle them, a decent respect to the opinions of mankind requires that they should declare the causes which impel them to the separation.

We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable rights, that among these are Life, Liberty and the pursuit of Happiness. That to secure these rights, Governments are instituted among Men, deriving their just powers from the consent of the governed, That whenever any Form of Government becomes destructive of these ends, it is the Right of the People to alter or to abolish it, and to institute new Government, laying its foundation on such principles and organizing its powers in such form as to them shall seem most likely to effect their Safety and Happiness.

Prudence, indeed, will dictate that Governments long established should not be changed for light and transient causes; and accordingly all experience heth shown, that mankind are more disposed to suffer, while evils are sufferable, than to right themselves by abolishing the forms to which they are accustomed. But when a long train of abuses and usurpations, pursuing invariably the same Object, evinces a design to reduce them under absolute Despotism, it is their right, it is their duty, to throw off such Government, and to provide new Guards for their future security.

(read the rest here...)

Thursday, July 3, 2008

I Love the Subway...

I love the New York City subway system. It's always been like a jungle of intersecting vines to me, and as Tarzan swung vine to vine, I swing from handhold to handhold through my turf.

I do not love the subway anywhere close to the way these two little boys do, though. This story, and the accompanying graphics, are utterly adorable. It's great that someone out there is actually pleased to hear the words "service change".

I hope that one day, riding the subway, I will encounter this family and see three little boys singing (in perfect harmony) all the stops on the 3 train. That would be one for the blog. I'll keep you posted.

(Boom de yada, boom de yada...)

Tuesday, July 1, 2008

Better Know an Arthropod: Bizzaro Lobsters!

Most people are familiar with the lobsters that grace many New England tables this time of year. The American/Atlantic/Maine lobster, Homarus americanus, is a well-known icon of the northeast part of the country and countless J. Crew summer prints.

Therefore, we're not going to discuss them further here today. Perhaps once I read The Secret Life of Lobsters I'll have something interesting to say about them beyond that they're apparently good with drawn butter.

This post is about the bizarro-lobsters of the deep seas. Sharon introduced me to a new one today, so let's view that one first!


The slipper lobster is not a "true lobster" -- it is instead more closely related to some of the other bizarro lobsters, the spiny and furry lobsters. They are achelate, meaning they have no claws. This makes them easy prey for humans, and indeed, if you Google "slipper lobster" you will find their tail meat for sale. (Of course, there is no claw meat to speak of.) Some of them are actually referred to as bugs, which is rather entertaining. No word yet on their position as a sustainable seafood. Not much seems to be known about them, if Wikipedia is at all accurate. Maybe it's better that way.

Next up: spiny lobsters. Popular for eating, also known as "rock lobster", and very colorful. Also, the only arthropod (as far as I know) that was immortalized in song by Fred Schneider (who is also very colorful). Interestingly, spiny lobsters have a unique form of sound production involving rubbing their antennae against a file-like protrusion. I'm not really sure what's going on there, but they're the only ones that do it, so that's neat.

I would tell you something about the furry lobsters, but there doesn't seem to be much to tell. (Except that if you start thinking too hard about the concept of a furry lobster, it can sort of hurt your brain.) Besides, you don't want to hear about true furry lobsters, you want to hear about this:

Kiwa hirsuta

Kiwa hirsuta, also entertainingly known as the yeti lobster, is not a true lobster or in the Achelate group with the other "bizarro" lobsters. Kiwa is in its own brand-new family, Kiwaidae, all by its lonesome. See, this beautiful, samba-dancing lobster, which you might be tempted to call a furry lobster but is not, was only discovered in 2005, chillin' at the bottom of the Pacific ocean. It lives on hydrothermal vents (so, maybe not chillin', per se), is pretty much blind, and may use all those "hairs" to detox after hanging around the vents, which spew mineral toxins.

My favorite part of this lobster is not that it's yellow, not that it's furry, and not that it's a deep-sea critter. (Although I love deep-sea critters, they're so bizarre!) My favorite part is that it was only found three years ago. I spent most of my life on a planet where no humans knew this thing existed! I suppose Kiwa knew it existed, if decapods can have self-awareness. But we did not know. There are still new things out there to find, if we look hard enough! (As I mentioned in my previous post, the world is just awesome.)

So there you have it. OK, true, none of these critters are true lobsters, but they all have lobster in their names and are therefore acceptable for a not-entirely-scientific blog post. (I didn't name the blog "Correctly Taxonomied Creatures," did I?) I hope you enjoyed your bizarro lobsters. Now please pass me some drawn butter, I want to dip my asparagus in it.