Why Do Crabs and Lobsters Turn Red When You Cook Them?

iStock / Creativeye99
iStock / Creativeye99

While they might be bright red when they hit your dinner plate, crabs and lobsters are usually brown, olive-green or gray when alive and in the wild (at least in the mid-Atlantic U.S.; crustaceans farther south come in a variety of vibrant colors). The dramatic color change during cooking has to do with the way certain biochemicals inside the shellfish react to heat.

Lobsters and crabs have a pigment called astaxanthin in their shells. Astaxanthin is a carotenoid pigment: absorbing blue light and appearing red, orange or yellow in color. While the crustaceans are alive, astaxanthin lies wrapped in the tight embrace of a protein called crustacyanin. The protein holds the pigment so tight, in fact, that it’s flattened and its light-absorption properties are changed. The astaxanthin-crustacyanin complex then winds up giving off a blue-green color.

These biochemical cuddle buddies get separated when a crab or lobster is cooked. Crustacyanin is not heat-stable, so introducing it to a boiling pot of water or a grill causes it to relax its bonds with astaxanthin, unravel and let the pigment’s true bold red color shine through.

An estimated 1 in 100 million lobsters are albino and don’t have any pigments in their shell. They’ll go cooked to the dining room the same color they went live into the pot: a ghostly gray-white.

Shrimp also have carotenoid pigments in their shells and flesh, and these are also hidden until they’re released by heat. So how do flamingoes, with diets heavy with carotenoid proteins but which usually don’t have kitchen access, take on the bright pink of their dinners’ pigments without cooking them? The proteins that mask the pigments not only unravel in the presence of heat, but also dissolve thanks to the acids and fats inside flamingos during digestion. The freed proteins then give birds’ feathers a soft pink hue.

Amazon's Under-the-Radar Coupon Page Features Deals on Home Goods, Electronics, and Groceries

Stock Catalog, Flickr // CC BY 2.0
Stock Catalog, Flickr // CC BY 2.0

This article contains affiliate links to products selected by our editors. Mental Floss may receive a commission for purchases made through these links.

Now that Prime Day is over, and with Black Friday and Cyber Monday still a few weeks away, online deals may seem harder to come by. And while it can be a hassle to scour the internet for promo codes, buy-one-get-one deals, and flash sales, Amazon actually has an extensive coupon page you might not know about that features deals to look through every day.

As pointed out by People, the coupon page breaks deals down by categories, like electronics, home & kitchen, and groceries (the coupons even work with SNAP benefits). Since most of the deals revolve around the essentials, it's easy to stock up on items like Cottonelle toilet paper, Tide Pods, Cascade dishwasher detergent, and a 50 pack of surgical masks whenever you're running low.

But the low prices don't just stop at necessities. If you’re looking for the best deal on headphones, all you have to do is go to the electronics coupon page and it will bring up a deal on these COWIN E7 PRO noise-canceling headphones, which are now $80, thanks to a $10 coupon you could have missed.

Alternatively, if you are looking for deals on specific brands, you can search for their coupons from the page. So if you've had your eye on the Homall S-Racer gaming chair, you’ll find there's currently a coupon that saves you 5 percent, thanks to a simple search.

To discover all the deals you have been missing out on, head over to the Amazon Coupons page.

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Each State’s Favorite Doughnut, Mapped

Life is like a box of doughnuts.
Life is like a box of doughnuts.
cottonbro, Pexels

Earlier this month, Dunkin’ unveiled the Spicy Ghost Pepper Donut, a picante pastry that piqued the interest of culinary daredevils across the nation. But for every brave soul eager to try it out, there were plenty of other Dunkin’ customers whose eyes never strayed from the basket of sweet, reliable glazed doughnuts.

It’s hard to overstate the popularity of the glazed doughnut. Data crunchers at The Waycroft, a luxury apartment complex in Arlington, Virginia, analyzed Google Trends searches from the last 12 months and found that it’s the apparent doughnut of choice in a staggering 15 states. But while folks clearly appreciate a time-tested treat, they’re also willing to make room in their hearts and stomachs for newer innovations; as Time Out reports, the second most popular kind of doughnut isn’t exactly a doughnut—it’s a cronut.

You can't go wrong with glazed.The Waycroft

The croissant-doughnut hybrid was invented by Parisian pastry chef Dominique Ansel just seven years ago, and it rapidly rose from humble beginnings at his New York City bakery to international acclaim. Since the cronut is, according to Ansel’s website, “rolled in sugar, filled with cream, and topped with glaze,” you could consider it a descendant of the sugar doughnut, the Bavarian cream doughnut, the glazed doughnut, or all three. Though the cronut’s birthplace, New York, did claim it as the state favorite, it’s definitely not a regional phenomenon—it topped the list in six other states, including both Dakotas, Montana, Vermont, Alaska, and Hawaii.

Other doughnut varieties, on the other hand, may be tied to certain regions. The only two states to choose blueberry doughnuts were Midwestern neighbors Indiana and Ohio; and two of the three states that favor apple fritters are in the Pacific Northwest (Washington and Oregon).

Do your own doughnut proclivities match the trends in your state? Scroll down to find out.

This map would make for quite an eclectic box of assorted doughnuts.The Waycroft

[h/t Time Out]