The wok is one of the most versatile and influential cooking instruments ever invented,
and the Chinese have been using it for up to 3000 years. The metal pan is distinguished
by its traditionally rounded bottom and large surface area, which makes it possible to braise,
boil, steam, and stir-fry foods all in one place. Another benefit of the kitchen tool
is something called wok hei. This Cantonese term was translated to “breath of the wok”
by food writer Grace Young, and it’s used to describe the unique, seared flavor the pan
imparts to food. When a wok reaches super high temperatures, it zaps excess moisture from the
ingredients and promotes caramelization to create more concentrated flavors.
The first woks were likely used for boiling and making stews, with stir-frying only becoming
popular after iron woks were introduced during the Song Dynasty roughly 1000 years ago. Iron is a
relatively poor conductor of heat, which actually makes it better at retaining heat when it does
reach the right temperature. Hot iron doesn’t cool down quickly as more ingredients are added
to the pan. This is essential to making a crispy stir fry. Today many woks are made from carbon
steel or even aluminum, which tend to be lighter, but you can still count using one as a work out.
Hi, I’m Justin Dodd. Welcome to Food History. Today we’re looking at inventions that shaped the
culinary world as we know it. Grab your cotton candy machines and your zucchini spiralizers
and let’s get started. Spoiler alert, neither of those made the cut.
Fire is often cited as one of the most important discoveries in human history,
and for good reason. As we discussed in our episode on the most important foods of all time,
fire had a huge impact on human development. You can watch that video to learn more. But
even as people began to cook, there was a lot that they couldn’t easily achieve with an open flame,
like evenly cooking food at controlled temperatures. For that, they needed ovens.
The earliest ovens date back 30,000 years to Central Europe, and they looked pretty different
from what you have in your kitchen at home. They consisted of a large pit dug into the earth,
lined with heat-conducting stones. Hot coals or ash provided consistent heat to the food,
and a layer of dirt on top kept that heat contained. These earth ovens cooked food
slowly at low temperatures, breaking them down and making the nutrients easier to absorb. From
Māori hāngi to New England clambakes, underground ovens are still used for celebratory feasts around
the world today—though what we cook with them has changed a bit over the millennia. Bones discovered
near ancient earth ovens indicate that mammoth was the main course at some of the first barbecues.
I don’t know why but mammoth sounds delicious. Humans have invented a lot of tools to heat food
since those early earth ovens. After the emergence of wood-fired brick ovens in ancient times,
gas ovens and electric stoves appeared in the 19th century. But The biggest recent leap in
cooking technology may be the microwave oven. Raytheon Company engineer Percy LeBaron Spencer
was visiting a lab testing microwave-producing magnetrons in 1945 when he noticed that the candy
bar in his pocket had melted. His dry-cleaning bill ended up being a small price to pay for the
flash of inspiration he had that day. As the story goes, Spencer sent out for some uncooked popcorn,
and when it popped in front of the active magnetron, Spencer realized that microwave
radiation could be used as a quick and convenient heat source for cooking. Later that year,
he filed a patent for the microwave oven. For ancient cooks, finding a way to keep fresh
food cold became just as important as cooking it. The Chinese practiced rudimentary refrigeration
3000 years ago by collecting ice and storing it. In the following centuries, the Egyptians,
Indians, Greeks, Hebrews, and Romans all developed ways to chill food and drinks, either by
harvesting snow and ice or making it themselves. The most impressive ancient refrigerator may be
the yakhchāls of Persia. Developed around 400 BCE, these pointed domes were designed to keep
ice frozen in a hot desert climate. Water from a nearby aqueduct would feed a chamber dug deep into
the cool sand beneath the structure. These ice houses sometimes featured wind catching mechanisms
that diverted breezes underground, where they would be chilled. Bâdgir, is still used in
desert architecture in Iran today. In addition to preserving food, Persians used refrigeration
to make delicious desserts. Traditional frozen treats like sharbat and faloodeh are products
of the yakhchāls of ancient Persia. Preservation is a major theme of food
history’s biggest breakthroughs. When modern canning was invented in the early 1800s,
eating nutritious meals on long journeys or during hard winters became more feasible.
But perhaps just as important as canning is the invention that made cans easier to use.
Believe it or not, the can opener came nearly five decades after the first metal cans. Before that,
people literally had to chisel away at their containers to get dinner. Animals.
While he may not have been the very first person to create a can opener—some sources cite the UK’s
Robert Yates—American inventor Ezra J. Warner may be the world’s most influential can opener
inventor. Put that on a mug. Warner patented his design for an early can opener in 1858. It
featured a blade sharp enough to penetrate the lid and a guard to protect the outside
of the can. By sawing the tool in a circle, users could remove the lid without a hammer
and chisel. Warner’s design never went mainstream, but it was used by soldiers during the Civil War.
Some grocers also used it to pre-open cans for customers. Can openers underwent various updates
until the 1920s, when Charles Arthur Bunker debuted a device that uses a cutting wheel
and a turnable knob. With a tool that made them easy to open, canned goods officially
went from survival food to convenience item. The cheese grater is another tool that makes life
in the kitchen easier, and it’s older than you might think. According to the Oxford Companion
to Cheese (my personal favorite companion to cheese), Mesopotamians in the third millennium BCE
had perforated bowls that might have been used to grate sun-dried cheese.
A Hittite text from a millennium later includes a term that could be translated to
‘grated’ cheese. By the 9th century BCE, there are clear descriptions and archaeological finds
of cheese graters from the Greek and Roman civilizations. Homer’s Iliad actually refers to
what may be a candidate for the oddest cocktail in history—wine, grated goat cheese, and barley meal.
Drop a name for this abominable and oddly intriguing cocktail in the comments below,
and we’ll see how long it takes for it to pop up at some hip Brooklyn speakeasy.
The invention of sliced bread is considered a high watermark for human ingenuity, but when
exactly did pre-cut loaves become standard? In 1928, Iowa inventor Otto Rohwedder filed a patent
for a machine that sliced entire loaves of bread at once. Not everyone saw the genius in his idea,
however. Bakers worried that slicing bread in-house would cause it to go stale faster or
even fall apart. To prevent this, Rohwedder recommended holding the slices together with
pins, which added an annoying hurdle to an item that was meant to be convenient. Eventually,
Rohwedder found a buyer for his machine in the Chillethecothe Baking Company, in Chillicothe,
Missouri. The company was set to debut Kleen Maid Sliced Bread on July 7, 1928. The day before,
the Constitution-Tribune published a glowing endorsement. The paper also ran an ad calling
the product, “the greatest forward step in the baking industry since bread was wrapped.”
That copy is believed to be the origin of the phrase “the greatest thing since sliced bread.”
That means “since sliced bread” is a quantifiable length of time, and if you’re watching this
in 2021, that length is about 93 years. Twenty-nine years BSB (Before Sliced Bread)
Scientific American wrote up an early blurb about the humble egg carton. While it’s difficult to
definitively say who invented it—the device wasn’t actually patented until 1928—this note from 1899
says that Robert J. Barkley of Kansas had created a carton “ … designed to contain a dozen eggs, and
to obviate the necessity of counting and of the danger of breaking the eggs by frequent handling.”
Sadly, there doesn’t seem to be much more info out there about Barkley, except that he died in 1905,
with his local newspaper noting that although “the public has been somewhat slow in adopting
[egg cartons] for general use . . . they are destined to some day be used everywhere.”
You’re gosh dang right, thank you for your service Barkley.
Early forks and spoons have been traced back to Ancient Egypt, but the spork wouldn't appear until
much later. American doctor Samuel W. Francis received a patent for his spoon-fork-knife
hybrid in 1874. This was just one of his many creative inventions. Other ideas he came up with
included a matchbox that ignited internally and a cane with an inner compartment for bus money.
Francis's new utensil wouldn't take off until the 1950s, when Hyde W. Ballard trademarked the
name "spork" and the plastic revolution made it easy to manufacture. Francis died in 1886
without knowing that his clever eating tool would become his greatest legacy.
I should also mention—while Francis’s proto-spork seemed to usher in the modern spork era (long may
its reign last), our always-wonderful fact-checker Austin Thompson did point us towards this Ancient
Roman utensil: as Austin said, “It’s not a spork, but it’s not NOT a spork!” Hard to argue.
Cling wrap is one of the most useful things to have in your kitchen, and it was invented
by accident. In 1933, a lab worker named Ralph Wiley at Dow Chemical was cleaning equipment being
used to develop dry cleaning products when he saw that a thin plastic film had formed inside a vial.
The material naturally adhered to surfaces while blocking water and oxygen molecules. Officially
called polyvinylidene chloride, Wiley’s boss John Reilly named the plastic Saran, supposedly
after his wife Sarah and his daughter Ann. The new product had many applications. Dow Chemical first
developed it as a spray that protected military fighter planes from the elements. Later, it was
used to make car upholstery and military combat boots. It wasn’t until 1949 that Dow Chemical got
rid of Saran’s off-putting odor and green color and applied its protective qualities to food.
Today, saran wrap is actually polyethylene, which may not be as clingy as the original material,
but has environmental benefits, and is probably healthier for use with food. Maybe saran wrap
wasn’t as revolutionary as the first oven or refrigerator, but it has saved
countless leftovers in the decades since. Thanks for watching Food History. Don’t forget
to name Homer’s cheesy-wine barley cocktail in the comments below. We’ll see you next time.