Will red meat really kill you?

A recent study in the Archives of Internal Medicine correlates eating any type of red meat with a higher risk of mortality. This 20-year study followed 110,000 adults and concluded that eating red meat of any kind may be risky. The lead author of the study, An Pan, said in an interview that "Any red meat you eat contributes to the risk."

Does this mean we all have to stop eating red meat at the risk of dropping dead? Probably not. The authors of the study themselves suggest modest dietary changes (eat red meat a couple times a week instead of every day) rather than red meat abstinence. Despite what may be suggested by many news organizations' headlines, this study does NOT establish a causative relationship between eating red meat and death. Instead, they have correlated these two things. Other factors may be at play.

There are other valid criticisms of the study, or at least limitations on what can be concluded given the data at hand. The authors do not differentiate between unprocessed and processed meat (things like bologna, bacon, and hot dogs) in the study. Since processed meats have already been shown to increase your risks for certain diseases, these specific types of meat may be more to blame than the unprocessed sort. Also, the study relies on self-reported data, which is not always the most accurate way to judge human behavior. Via BoingBoing, a great explanation of the study, what it has found, and what it has not found, is located here. It's recommended reading for all carnivores.

The take home message seems to be that, for now, although we're not certain that eating red meat will harm you, it seems to be correlated with an increased risk of death. We do know that consuming certain types of red meat is likely to increase your risk of certain diseases, so it's a good idea to reduce your intake to no more than a couple times a week, and to balance it out with other types of protein as well as lots of fruits and vegetables, the consumption of which seem to be correlated with good health outcomes.

Since meat is also expensive, calorie-dense, and producing it is environmentally taxing, that seems to be pretty good advice for your health, your wallet, and the environment.

(Image: Beef!, a Creative Commons Attribution 2.0 image from Michael Cannon's photostream)

Science of Beating Eggs

My friend Lynn tipped me off to a neat story on the NPR website about the science of beating eggs. Read it if you'd like to get some pro-tips (from a real chef!) on beating egg whites into a foam for use in a souffle (or other whipped-egg-white application, such as meringue).

The first trick is to separate your eggs (that is, separate the yolks from the whites) without letting any of the egg yolks contaminate your whites. This is important because, while the egg white is entirely made of protein, the yolk contains some fat. When you whip the egg whites, you denature some of the proteins, which unfold and expose some hydrophobic areas. These hydrophobic areas would rather stick to each other than to the surrounding water, so the proteins stick together, creating a sort of net that can surround air bubbles, creating a foam. This foam is what makes whipped egg whites fluffy. If you contaminate your whites with the fat from the egg yolks, the hydrophobic areas of the egg white proteins will interact with the fat from the yolks instead of each other, leaving you with no net of denatured protein in which to catch bubbles. No bubbles means no foam.

Another note: if you over-beat the egg whites, continuing to beat them after a proper foam has formed, the egg white proteins will coagulate completely, sticking together so strongly that they force out all of the liquid between them, leaving you with a clumpy, separated, egg white mess.

If you're more of a visual learner and are interested in learning this useful kitchen technique, check out this how-to slideshow from Serious Eats or this excellent segment on souffle from the ever-informative Alton Brown from Good Eats.

Related: The Science Behind Poaching an Egg

(Image: Soufflé, a Creative Commons Attribution 2.0 image from David_Turner's photostream)

Caffeine and the Brain

Over at Lifehacker there is a really informative post about what caffeine actually does to your brain. Basically, it prevents your brain from slowing down. It isn't actually a stimulant, but a de-depressant. Also, you get acclimated to it pretty completely, so that it doesn't affect you anymore, except when you don't have it. Sigh. Still, it's a great addiction to indulge in on a rainy New York day like today.

Chemical Weapons in Your Kitchen

(Leeks via Wikimedia Commons)

In the recent NY Times Dining section there is a great article (by noted food author Harold McGee) about a new book by Harold Block called Garlic and Other Alliums: The Lore and the Science. A
apparently it's a little technical (and a little pricey), but McGee's article breaks down some interesting stuff about these ubiquitous kitchen-dwellers.

Alliums, the plant family that includes onions, garlic, and leeks (among others), have been used by humans as food for... well, a long time. But did you know that they can damage the red blood cells of dogs and cats? Or that the sulfur-based compounds that give garlic its distinctive taste can get into your mouth if you rub a clove on the bottom of your foot? Go try it RIGHT NOW! (And tell me how that works out for you...)

Pardon the Interruption...

 (scary cake, via The Kitchn)

I know I've been slacking off on posting lately. It's been mostly due to the impending end to my graduate student career and related thesis writing activities. Basically, posting is going to be very sparse until August. Until then, I'll try to keep you updated with the goings-on in the food interwebs. Also, my CSA is starting next week, so I'm planning to have some related posts on seasonal veggies.

For now, please entertain and inform yourselves with the following items of interest:

Snake Oil in Your Snacks - Don't believe everything you read on food packaging, or How yogurt isn't going to solve all of your bowel problems.
The Bisphenol A Saga Heats Up - This endocrine disrupting compound is showing up more and more places - previously, in Nalgene bottles and other plastic bottles, and now in most canned food, too.
Dismal Reports on Dietary Supplements - In other snake oil news, food supplements are mostly bunk.
Your Fetus Can Taste Your Food - Turns out, what you eat while pregnant has an effect on what your baby will prefer to eat once it's born.
Why Bananas Turn Black in the Fridge - Cold damages these tropical fruits and causes their cells' vaculoles to leak causing phenol oxidation. Got that?
Do Spices Really Only Keep For Six Months? - Unsurprisingly, they don't spontaneously go bad after this period, but ground spices do lose flavor over time.
Keep 'Em Separated - Why you have to keep egg whites and yolks separate if you want to whip up some nice foamy egg whites. You don't want lipids in your protein foam do you? DO YOU?!
Eat Your Way to a Better Tan - Science says, eating your veggies can help give you a healthy, sun-kissed glow.
Vodka Watermelon - Okay, there isn't much science in this post, but there should be. Osmosis, anyone? Also, delicious boozy watermelon... mmmmm....

Finally, because it is awesome, this video on DIY Plum Wine and Plum Syrup. Japanese green ume plums are in season now, if you can find them:

Speaking of "in season," its finally getting into real summertime here in the Northeast, so get thee to a farmer's market! Radishes and snap peas and strawberries, oh my!

Science Cookies!

I get so excited when I find people combing my favorite (and only) livelihood (science) with my very favorite hobby (cooking). There is a super crafty and exciting example of these two worlds colliding at Not So Humble Pie, where Ms. Humble, blog proprietor, has amassed an awesome assortment of science themed cookies (from herself and other geeky bakers). Can you recognize the ones above? They're little electrophoresis gels. Squee! Check them all out here.

(via The Kitchn)

Eating to Starve Cancer

There is an interesting summary of a presentation by Dr. William Li from the TED conference at BoingBoing. His talk discussed foods that prevent angiogenesis and thus prevent cancer from becoming deadly. File under: more good reasons to eat your fruits and veggies.

The Science Behind Poaching an Egg

(via Tastespotting)

Poached eggs are delicious – at least I think so. I suspect that a number of other people do, as well, yet they remain relatively unpopular when compared to other methods of egg preparation. This may be because oftentimes the result of boiling an egg without its shell resembles Egg-drop soup more than Eggs Benedict.

Science to the rescue! Actually, poaching an egg is not that difficult, especially if you think a little bit about what’s going on inside your pot. With a little bit of know-how behind you, preparing perfect poached eggs, without space-hogging and expensive unitaskers, is no problem.

What’s going on when you cook an egg? The answer is all about proteins. Egg whites are made of proteins and water. Proteins themselves are large (macro) molecules that consist of long chains of smaller molecules called amino acids folded up into complex structures. When proteins are subjected to heat, they denature, that is, the chains unfold and lose their structure. This often causes the proteins to lose solubility (they can no longer be dissolved in liquid). In the case of ovalbumin, the main protein component of egg whites, this causes the egg white to solidify and look white and cooked. The key to perfect poached eggs is to have this happen as fast as possible when cooking the egg, before the egg white has a chance dissipate into the water in the pot.

How to do this? Well, it has been shown that ovalbumin is more easily denatured at acidic pH¹. This is the science behind why vinegar is often added to egg poaching water. This recipe outlines the basic approach I take. A simple experiment shows that adding 1 tsp. (4.9 mL) of white vinegar (5% acetic acid v/v) in 2 quarts of NYC tap water (1.9L) changes the pH from 6.75 to 3.43 at room temperature (25C) (Remember that pH 7 is neutral, lower pH is acidic, and higher pH is basic or alkaline). At a simmer (95C), the pH of tap water is changed from 6.84 to 3.87. This more acidic pH, combined with the heat of simmering water, rapidly denatures the ovalbumin in the egg whites, creating a coating of cooked egg that the interior of the egg is trapped in while cooking. This prevents the egg from falling apart and the result is a perfectly poached egg.

Poached Egg Protocol:

Materials: 1-4 fresh eggs (egg white proteins break down over time, resulting in a runnier white that spreads out more in the pot), 2qt or larger pot, small bowl, white vinegar, slotted spoon, paper towel

• Bring ~2qt. water to a low simmer (NOT a vigorous boil) and add 1 tsp. white vinegar.


• Crack one egg into a small bowl before sliding it into the simmering water so as not to break up the egg on it’s way into the water.


• Repeat for subsequent eggs, spacing eggs out from each other so that they heat quickly and evenly and don’t stick together.


• Cook eggs 2-3 minutes (or until desired done-ness level). Eggs will continue to cook as long as they are hot, so expect them to cook a little more after they have been removed from the pot.


• Evacuate eggs to a paper towel on a plate using a slotted spoon.


• Bon Appetit!

¹Koseki et al. Conformational Changes in Ovalbumin at Acid pH. J Biochem.1988; 103: 425-430

Carl Sagan's Apple Pie

Lulz




(via Serious Eats)