The Chemistry of Pie

A little pre-Christmas last-day-of-class treat: 20 minutes on The Chemistry of Pie.

The Coffee Bean Wall Shows the Science and Color of Coffee

If you're vacationing in Orlando at the newly opened Cabana Bay Hotel (Universal Studios), you might accidentally run across some colorful science in the Starbucks there. They have a "coffee bean wall" that shows the progression of beans, from green to red (peeled) to light and dark brown (roasted less vs. more). It makes for a nice-looking wall but the science of coffee is behind it. Well, I don't know what's actually behind it because I haven't been there but maybe I'll fix that on a future vacation. For example, the dark-roast beans have less caffiene because the heat has burned the caffiene right out of them. [Thanks to Theme Park Insider for the photo tour that showed this.]

Green Tea, Dark Chocolate, and Zinc Actually Work

This infographic showing evidence for supposedly "healthy" supplements has been around since 2010, but it's the first time I've seen it. I must be a glass-half-full type because, rather than get depressed about the large number of "not worth it" substances, I'm pleasantly surprised to see dark chocolate (for blood pressure), green tea (for cholesterol, not necessarily cancer), and zinc (for colds) supported by actual evidence. This fits my impressions but I'm glad to see someone's worked harder at gathering more than just impressions. Now, I really need to take some vitamin D, especially considering Seattle's lack of sun.

Coffee Charts

Here's two coffee graphs. Consider them figures for a great unpublished coffee-drinking paper. The first would be from the results section (tasting) and the second is methods (brewing). Click to enlarge:

 

 

DIY Molecular Gastronomy

This article describes itself as Molecular Gastronomy but it's really just cooking with possibly-hard-to-find ingredients. Most of the chemistry is biochemistry, especially the transparent ravioli with an explanation that involves phospholipids. I am going to have to look into that one a little more because I'm not sure the explanation explains. But the point of this is first to do something cool with chemistry and only second to explain it: the proof is in the pudding, or the parfait, or whatever the end result is. This article will be bookmarked for possible inclusion in next year's biochemistry lectures ... or could it form the basis for at-home labs? Something to consider.

They Don't Make Pyrex Like They Used To ...

I use Pyrex in both the lab and the kitchen, and always thought because the label was the same, that the kitchenware was the same as the labware. Alas, I was wrong.

In the 90's Corning changed the kitchen Pyrex recipe from borosilicate to soda lime silicate. So a pan that used to be able to handle a 300 degree F shift in temperature can now only handle 100 degrees F. Lab Pyrex is still borosilicate, although I still hold my breath when pouring something very hot, just by reflex, and the upcoming video only enhanced that reflex.

The silver lining is that Consumer Reports made a nice video showing just how shattering the oven-to-freezer move can be now. There's always a certain thrill to watching stuff blow up (especially if there's a safety shield between you and the explosion):

Food Detectives in the Classroom

The New York Times recently ran a story in which the reporter (a film-maker) took five everyday food items and ran them through a bomb calorimeter. Lo and behold, the calorie counts on the packages don't match the claims, and four out of five were too high, adding up to an extra 500 calories.

I have mixed feelings about this study. Sure, some of the calorie counts are a little higher than claimed -- but the error bars in the bomb calorimeter's findings were not reported. Why are we trusting the instrument so much? This is far more about journalism than it is about science.

And yet, and yet ... it could be about science. What if a chemistry course on calorimetry had each lab group buy different kinds of food and test its calories, then compare to the claimed calories? They'd learn bomb calorimetry but they would really learn whether calorie counts are accurate, which is more interesting because it's what the calorimetry is for. If it's done by students doing it for the first time, their numbers may not be as accurate, but I'm not sure they're so accurate in the first place. It would be like the lab exercises I've read about in which students use DNA barcoding to check whether the fish at the supermarket is indeed the species that the label claims it is. Instant relevant lab exercises -- and if the students like, they can inflate it into a Michael-Moore-style expose more approprite for a communcations class. Feel free.

Or a newspaper as venerable as the Times could talk about error bars and point out that not all differences are truly significant ... but that may be too much to ask. Replication and journalism may be philosophically at odds. So be it.

A Home Experiment with Hot Chocolate

Do indeed try this at home: Make some hot chocolate, and put some in an orange cup and another in a white cup. The orange cup should taste better. Now, I've heard this in a recent report, but you should be skeptical. Don't take my word for it. Try it for yourself. And remember, repeated trials are the only way to be truly scientific about it. I think a few dozen should get your error bars down to a reasonable level.

If all science labs were like this we would have quite a few more students.

(I do wonder about the studies reported in which blue drinks quench thirst better than red ones ... are we talking a light blue or the Tid-y-Bowl blue of certain Gatorade flavors? Because I cannot abide the latter, even if it will quench thirst more efficiently. Just not natural.)

Another Reason to Like Gummi Bears

Gummi bears are already my favorite candy, but the fact that they do THIS when you add one (just one!) to heated potassium perchlorate piles on the reasons to love 'em:



Oxygen is a powerful element, no? It's what turns a gummi bear into a firework (and CO2).

"Why Are You Putting So Many Chemicals in Your Food?"

Most chemists' pet peeve is the label on food that says "chemical-free." Last I checked, most food was made from atoms, and all food is therefore made of chemicals. Nathan Myhrvold researched chemistry and food, published the five-volume, beautiful (but inaccessibly priced) Modernist Cuisine, and in much briefer form summarizes the counterargument to the "chemical-free" label here. My favorite part is this connected article in which he opens up his pantry and tells you what chemicals are in there and why. There's a recipe for chemical-laden grilled cheese if you like.

I sense some biochem exam questions coming on ... but what do you do if you run out of sodium citrate? It's not like you can run over to your neighbor and ask for a cup ...

Soda Temperance!

It's funny to think about it, but if root beer came about in part from the prohibition on real beer, then now we may need a temperance on root beer, due to its sticky, corn syrupy, calorie-adding mass. I don't trust soda every day, it's one of the reasons I switched to green tea for lunch, and I'm not regretting it. (In this case, a Lent giving up of soda turned into a longer-term temperance of soda!)

The quote that reminded me of this was in an article on how soda fountains are coming back:

“Soda should be special,” Mr. Nocito said. “Coke and Pepsi killed it for everyone, in my opinion.”* It seems that if you use fresh fruits and not mass-produced sludge to flavor sodas, you can make unique and even slightly healthy combinations. The problem is you have to go to a counter, you can't just grab a bottle off the shelf. Let me tell you, though, this is a good problem to have. It should be special, and there are benefits from having less of it!

Here is the article about the new-fangled (or should it be old-fangled?) soda shops and some of the flavors. I have a hankering for an egg cream and I've never even had one.


* However, I can attest to the power of a cold Coke on a hot summer day in the South. So we'll just say Pepsi killed it for everyone, OK?

Two Stories I Don't Want to Forget

1.) I had a student tell me that a biochem homework question -- about why emulsifiers are required to make mayonnaise that doesn't separate out -- actually helped him reason through why a peanut sauce he had made was separated out, and then he solved it by using biochemistry to add a little egg yolk as an emulsifier. Biochemistry is useful! (For peanut sauces at least.)

2.) The same student told me his dad was sitting on a plane next to a medical student from a big state university in the midwest, and they started talking about how his son was taking biochemistry, and the med student mentioned he was listening to some biochem lectures from iTunesU ... and turns out the med student was listening to my lectures! A good reminder that I have no idea what work the iTunesU lectures are doing while I'm otherwise occupied.

Now, I don't think this particular student who told me these stories was angling for a better grade on the final that I'm going to start grading any minute now ... but you gotta admit these are some good stories!

Instant Easter Eggs

(Idea from Harold B. White published in Biochemistry and Molecular Biology Education Vol 28 No 1 pp 35-36, 2010.)

If you put eggs under a UV light they will glow scarlet. The same pigment is what makes earthworms purplish, and it is very light sensitive, meaning it's why earthworms fry in the sunlight (say, after a good rain when they come out).

More at this link. I sense a future biochemistry demo!

Book Review: The Science of Cooking

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Peter Barham, a physics instructor and food science lecturer, describes his hobby of combining cooking with science in this book. It explained quite a few things I did not know, and I've been teaching biochemistry for almost a decade. On top of that, it gave me test questions and an idea for a new lower-division course about biochemistry with labs in the kitchen. The book is straightforwardly written and generally does a good job simplifying complex situations. I especially like the way Barham describes the trade-offs that make certain kinds of cooking (puff pastry, souffles, etc.) so tricky, and then he describes how to avoid those trade-offs. An easy souffle? I think I'll have to try that one myself.

Fruit MRI

So simple yet so amazing. This site posts the results of what happens when fruits are put into an MRI. The resulting animations are flat slices through the middle of the fruits, as if you have Superman's X-ray vision at a produce stand. Check it out!

Thanks to Francis Lam for the heads up.

A New Reason to Go to Canada

In the Seattle Times today, an article about eating in Vancouver, and behold, "Japadog"! On-street vendors selling Asian-themed bratwurst, with radish, soy sauce, rice, seaweed ...

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I don't know about this Olympics thing, but let me tell you, I'm trying to figure out how to get up to Vancouver soon to try one of those.

Tea Notes

Just some bullet points:

-- Lipton Black Label Tea is actually Not Bad. Not fabulous either, but it might be better than my standard cheap black teas.

-- Teavana's Dao Ren is the king of green teas. They say it's grown in a fruit orchard to take up fruit scents. I think it's grown in a poppy field which may explain its addictive nature. Of course, they're running out of it soon ...

-- Teavana doesn't stock unflavored Rooibos anymore. This wouldn't be a big deal except I just figured out how to make a tea latte that taste just like the Starbucks Rooibos Vanilla from Rooibos + vanilla syrup + half and half AND it's caffeine free. Republic of Tea and Twinings both make OK Rooibos but I want loose leaf whole leaves!!!

-- Got a Dragonwell from the tea festival that looks like little flat green rosemary leaves. It's very good (better be 'cause it's expensive), and it's quite novel to be steeping actual leaves rather than curled up things.

Best Science-Themed Bar and Grill in Boston

Just up the street from M.I.T., and next to the M.I.T. museum (which expressly forebade me from posting pictures on a blog on the ticket, so sorry about that), there is a small bar and grill called "Miracle of Science." This is its menu. If you have to ask what I ordered then you don't know me very well. OK, one hint: It's near to where rubidium should be. :)

Fancy Fast Food

You know, I've always wondered if they could do a cooking show on the Food Network where the chefs would have to whip up a dish starting only with readily available pre-cooked fast food. This website basically takes that idea, and then puts the dishes that result on fancy plates so they look like they came from a fancy restaurant. It's very funny ... and who knows, might be useful.

Here's the site so you can see for yourself. The Burger King quiche looks good enough to try.
http://www.fancyfastfood.com/

The British and Bicarbonate

A biology colleague asked me yesterday if I knew why the British put sodium bicarbonate in the water when they boil their veggies. Leaving aside the question of why anyone would want to emulate the British when it comes to cooking, he thought it would have something to do with keeping the chlorophyll green. Chlorophyll is a little net with four nitrogens on the inside that grab hold of magnesium, which gives it the green color that lets it absorb light from our yellow sun so effectively. When you boil vegetables and jostle that magnesium around, sometimes it falls out. How does bicarbonate prevent that?

Well, I didn't know, but I had a book that did: On Food and Cooking by Harold McGee. This is a wonderful reference that I really need to read cover to cover sometime. But it had a whole section on this.

It turns out acid (positively charged) can displace the magnesium (positively charged), and it leaves a big hole in the chlorophyll, making it yellow. Extra bicarbonate absorbs extra acid and the magnesium stays put, and the chlorophyll stays green. An interesting twist is that copper can displace magnesium too, but because copper's a metal the chlorophyll stays nice and green, so some old cookbooks say you can keep your veggies green by boiling them in copper pots. Very cool and it does work ... except for the fact that copper is a poison!

So there you have it, British cooking is poisonous. (Well, the copper pot version. Actually, I shouldn't make fun of British cooking so much -- I absolutely love tea and bangers and mash!)