CLOSE

Explore the Origins of French Cuisine With This 200-Year-Old Map

France is known as the unofficial culinary capital of the world to many, and for good reason. French products like brie, cognac, and champagne are enjoyed far beyond the nation’s borders. For a look at where France’s most beloved gourmet exports originated, refer to the early 19th-century map above.

As highlighted on Atlas Obscura, the "Gastronomical Map of France" was created by Jean François Tourcaty in 1809. A scan of the map takes viewers through the country’s most delectable landmarks, from Roquefort, home to the region’s pungent blue cheese, to Dijon, the birthplace of the world-famous mustard. While some places are no longer producing their signature delicacies, many of them are still home to the food and wine they were known for 200 years ago.

The map first appeared in the book Cours Gastronomique, which was written by Charles Louis Cadet de Gassicourt, the possible illegitimate son of Louis XV. The culinary tome was published a decade after the French Revolution, around the same time the fine dining industry was starting to explode in France.

For more unique maps from history, check out Cornell University’s PJ Mode Collection of Persuasive Cartography online.

[h/t Atlas Obscura]

All images: Cornell University // CC BY-NC-SA 3.0

nextArticle.image_alt|e
iStock
arrow
science
Researchers Pore Over the Physics Behind the Layered Latte
iStock
iStock

The layered latte isn't the most widely known espresso drink on coffee-shop menus, but it is a scientific curiosity. Instead of a traditional latte, where steamed milk is poured into a shot (or several) of espresso, the layered latte is made by pouring the espresso into a glass of hot milk. The result is an Instagram-friendly drink that features a gradient of milky coffee colors from pure white on the bottom to dark brown on the top. The effect is odd enough that Princeton University researchers decided to explore the fluid dynamics that make it happen, as The New York Times reports.

In a new study in Nature Communications, Princeton engineering professor Howard Stone and his team explore just what creates the distinct horizontal layers pattern of layered latte. To find out, they injected warm, dyed water into a tank filled with warm salt water, mimicking the process of pouring low-density espresso into higher-density steamed milk.

Four different images of a latte forming layers over time
Xue et al., Nature Communications (2017)

According to the study, the layered look of the latte forms over the course of minutes, and can last for "tens of minutes, or even several hours" if the drink isn't stirred. When the espresso-like dyed water was injected into the salt brine, the downward jet of the dyed water floated up to the top of the tank, because the buoyant force of the low-density liquid encountering the higher-density brine forced it upward. The layers become more visible when the hot drink cools down.

The New York Times explains it succinctly:

When the liquids try to mix, layered patterns form as gradients in temperature cause a portion of the liquid to heat up, become lighter and rise, while another, denser portion sinks. This gives rise to convection cells that trap mixtures of similar densities within layers.

This structure can withstand gentle movement, such as a light stirring or sipping, and can stay stable for as long as a day or more. The layers don't disappear until the liquids cool down to room temperature.

But before you go trying to experiment with layering your own lattes, know that it can be trickier than the study—which refers to the process as "haphazardly pouring espresso into a glass of warm milk"—makes it sound. You may need to experiment several times with the speed and height of your pour and the ratio of espresso to milk before you get the look just right.

[h/t The New York Times]

nextArticle.image_alt|e
iStock
arrow
Live Smarter
Why You Should Think Twice About Drinking From Ceramics You Made by Hand
iStock
iStock

Ceramic ware is much safer than it used to be (Fiesta ware hasn’t coated its plates in uranium since 1973), but according to NPR, not all new ceramics are free of dangerous chemicals. If you own a mug, bowl, plate, or other ceramic kitchen item baked in an older kiln, it may contain trace amounts of harmful lead.

Earthenware is often coated with a shiny, ceramic glaze. Historically, lead has been used in glazes to give pottery a glossy finish and brighten colors like orange, yellow, and red. The chemical is avoided by potters today, but it can still show up in handmade dishware baked in older kilns that contain lead residue. Antique products from the era when lead was a common crafting material may also be unsafe to eat or drink from. This is especially true when consuming something acidic, like coffee, which can cause any lead hiding in the glaze to leach out.

Sometimes the amount of lead in a product is minuscule, but even trace amounts can contaminate whatever you're eating or drinking. Over time, exposure to lead in small doses can lead to heightened blood pressure, lowered kidney function, and reproductive issues. Lead can cause even more serious problems in kids, including slowed physical and mental development.

As the dangers of even small amounts of lead have become more widely known, the ceramics industry has gradually eliminated the additive from its products. Most of the big-name commercial ceramic brands, like Crock-Pot and Fiesta ware, have cut it out all together. Independent artisans have also moved away from working with the ingredient, but there are still some manufacturers, especially abroad, that use it. Luckily, the FDA keeps a list of the ceramic ware it tests that has been shown to contain lead.

If you’re not ready to retire your hand-crafted ceramic plates, the FDA offers one possible solution: Purchase a home lead testing kit and analyze the items yourself. If the tests come back negative, your homemade dishware can keep its spot on your dinner table.

[h/t NPR]

This piece was updated to clarify that while lead may be present in antique ceramics and old kilns, it's no longer a common ingredient in ceramic glazes.

SECTIONS

arrow
LIVE SMARTER
More from mental floss studios