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FriOct 25

Sourest Day – October 25, 2024

It’s Sourest Day, which means it’s time for a sensation overload that will make your mouth explode this October 25. We’re not just talking sucking on a lemon or boatloads of over-sugared gummies. Today is a day for all things sour — from candy to kimchi, sour foods can be an everyday part of our lives! Grab some citrus and some yogurt, we’re about to get puckerin’.

History of Sourest Day

Sour candies, sour fruits, sour vegetables, sauerkraut. Sour foods have been a staple in human diets around the world for centuries. And while the term ‘sour’ typically brings to mind a puckering candy or a rather irate person, it really encompasses so much more. 

Sour foods have been on Earth much longer than humans. In fact, the first crop of lemon trees has been traced to over eight million years ago. Since then, dozens of cultures have experimented with their own take on sour foods, most of which, as it turns out, are good for your gut due to their similar fermentation processes. 

In the 1st century B.C., Koreans had all but perfected the fermentation of cabbage and other vegetables in a dish we now know as kimchi, while 16th century Germans experimented with fermenting cabbage mixed with salt, creating the classic sauerkraut dish we know and love today. 

Of course, sour isn’t just for vegetables. The Parisians ‘invented’ lemonade as we know it today in the 1640s by mixing lemon juice with water and honey, which quickly became a summer staple across Europe, eventually leading to the classic American lemonade stand that debuted in New York City over 130 years ago. And it wouldn’t be until the 1970s that sour candies took off, cementing sour’s legendary association with pucker mouths. 

While there are tons of rich food history and culture to celebrate on Sourest Day, it’s worth noting that the holiday was never invented for sour foods: a fellow in Ann Arbor, Michigan, launched Sourest Day in 1977 as a way to celebrate his good friend whose last name was, you guessed it: Sauer.

Sourest Day timeline

1000 A.D.
The First Glass of Lemonade is Sipped

Egyptian records cite the first lemonade type of drink, made with lemons and dates.

18th century
Sweet and Sour Chicken Takes Off

The popular dish originated in China before taking off in the U.S. a couple hundred years later.

Warheads are Invented

The classic sour bombs that few can handle are invented in Vietnam.

Early 2000s
Korean Food Craze Sweeps the U.S.

Thanks to the rise of food trucks and Korean restaurants in the Hell’s Kitchen borough of N.Y.C., Korean food redefines Asian-American.

Sourest Day FAQs

What makes foods sour? 

Sour is one of the five main tastes detected on the human tongue. Foods that are highly acidic trigger that part of our tongue to produce a sour taste, which prompts the brain to release that sour sensation that comes from too many Warheads and results in the classic pucker face. 


What is the sourest food on earth?

Toxic Waste, the candy, is said to be the sourest candy out there. The umeboshi sour plum is a Japanese delicacy where the plum — related to normal plums and apricots — is preserved in salt, making it the sourest fruit. Rhubarb is said to be the sourest vegetable, even though it’s typically used for sweets!


What foods are sour besides candy?

Sour candy may be the most popular type of sour food, however, it certainly is not the only one. Citruses fruits and probiotics are packed with that classic pucker-causing sensation. Buttermilk, yogurt, kimchi, and kombucha all pack a similar punch.


  1. Give your day a little pucker

    Skip the Minute Maid and milk. On Sourest day, replace your standard bevvies with a more lemony-lemonade or try a glass of buttermilk with dinner. Make your day even sourer by opting for a sour version of your favorite candy to snack on.

  2. Host a sour-off

    Grab an assortment of the sourest candies you can find and some friends. It’s time to taste test them all … and see who can withstand the most puckering.

  3. Turn that frown upside down

    Know someone who’s a bit grumpy or maybe even … sour? Do something nice to brighten up their day and change that mood! Send them some flowers, a cookie bouquet, or even some sour gummy candies!


  1. There are hundreds of types

    Depending on the local flavors, vegetable availability, and refrigeration components, kimchi varies around the world.

  2. It’s packed with probiotics

    It’s not just the vegetable base that makes kimchi so healthy: the fermentation process creates tons of probiotics, making it good for your gut!

  3. Korea is obsessed with it

    Sources claim Koreans eat 57 pounds of the stuff each year.

  4. It will last

    Keep it refrigerated between 32 and 41°F and that little jar will last up to six months.

  5. It has an entire museum dedicated to it

    A museum in Seoul, South Korea, outlines the history of the popular preservatives and even teaches D.I.Y. kimchi.


  1. There are hundreds of types of sour candy

    Whether you’re a fan of gummies, hard candies, or lollipops, there’s a sour candy for you. Grab your favorite flavor in the form of hard flavor bombs, soft gummy worms, or even sprays and gum.

  2. It’s the perfect excuse to order Chinese take out

    Chinese restaurants have long been the peddlers of the perfect combination: sweet and sour. This combination has been perfected across classic dishes like egg rolls and lemon chicken, and is prevalent in just about all of the menu. Whether you’re looking to dip crab rangoons in the classic sauce or chow down on sweet-and-sour chicken, your favorite take out spot is bound to have it all.

  3. Lemonade stands take us back

    Why is it that store-bought lemonade tastes better when you buy it from two kids selling it for a quarter? Regardless of the reason, it certainly does! Remember when you were trying to raise some money for a new toy with your mom’s secret recipe? Pay that nostalgia forward the next time you see a stand and enjoy the cool, refreshing zip.

Sourest Day dates

2024October 25Friday
2025October 25Saturday
2026October 25Sunday
2027October 25Monday
2028October 25Wednesday

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