The women were accused of selling germs at first
Yogurt sellers in South Korea make their customers happy
There are about 11,000 yogurt sellers in South Korea.
The women offer a variety of products to their customers.
An hour before dawn, Kang Hae Jong was wandering about her portable, battery-powered refrigerator, gently moving through the alleys in Chungdam-dong, south of the capital, Seoul.
Her car was stopped and moved between apartments and office buildings, from door to door, and from office to office, entering the secret numbers, to enter the buildings easily, as if she was another family member or a colleague at work.
But to her loyal clients, the yogurt seller is known as "Yakult Ajuma."
Yogurt sellers have been wearing uniforms in South Korea for decades, and they are always smiled and greeted.
The yakult is sold from refrigerated trolleys, a sweet yogurt created in Japan in the 1930s.
"Ajuma" is a Korean word, often used lovingly to describe middle-aged mothers.
"I serve yogurt, but I also offer joy and energy," says Kang, 47, who started the profession in 2012 and knows her customers' demands well.
Follow-up: "People, especially the elderly, are satisfied to see a cheerful, hard-working woman, and some of them eventually decide to buy my products."
In the early 1970s, the government introduced agricultural subsidies to boost the country's livestock.
The growing cow trade created an excess of milk, because Koreans at that time had little appetite for dairy products.
So, South Korea presented a joint venture with the Japanese "Yakult Honsha", which was a sweet drink made from fermented milk, which later became part of healthy food.
Yakult Honsha was already using a network of women for home delivery in Japan, and the Korean company also adopted this idea.
In 1971, dozens of women looking for jobs to support their families' income became the first "Yakult Ajuma" in the country.
The work was hard, and due to the lack of a cold store for fresh drinks, the women had to pull out carts filled with ice to sell the yakult.
And customers weren't coming in often.
Initially, the women were accused of selling "germs."
The company launched an intensive advertising campaign entitled "Good for stomach health".
And now there are clients for this sweet yogurt everywhere, including popular neighborhoods and hillsides, gleaming apartment buildings, factories and even Parliament.
There are nearly 11,000 yogurt sellers in South Korea, which is the nation's largest home delivery sales network, and is only for women.
Half of them can be seen wandering around Seoul, in their pickups.
Thanks to "Yakult Aguma", for promoting dairy products in South Korea, they are so ubiquitous that they have become popular culture.
A folk song appeared about the work of women yogurt sellers.
Jun Duc Sun (49 years old) began working in "Bongcheon-dong", southwest of Seoul, as "Yakult Aguma", 17 years ago.
Since then, the upland area, dotted with auto repair shops and sewing factories, has been her favorite place to sell.
Sun, for the first time, carried yogurt in a small cart filled with ice-blocks to keep her drinks cool.
When the street becomes very narrow or steep, or when she faces stairs, she carries her products in a cool bag over her shoulder.
"Imagine how it felt when I encountered a stretch of three tracks of strenuous climbing," says Sun. "But I always walked our streets, whether it was very hot, or it was snowing, or it was raining."
In 2015, as the proliferation of refrigerated trucks and convenience stores led to intense competition in the market, Korea incorporated the "Yakult Koo Ko", which looks like a golf cart, which helped spur sales by allowing female vendors to sell in a wider area, on busy streets.
The refrigerator, which has a capacity of 220 liters, contains cheese, cold yogurt drink, fresh eggs and meats. The women of "Yakult Aguma" are part of the wave of women who joined the workforce in large numbers, in the 1970s.
Often these women were driven by a strong desire to finance their children's education to raise the status of their families.
The saleswomen were violating traditional gender roles, as women were expected to be shy and focused primarily on housework.
Most of the "Yakult Ajuma", today, are in their forties, and tend to work in the same neighborhood throughout their careers, and stay in the job for 12.5 years, on average.
In the early 1970s the government provided agricultural subsidies to boost the country's livestock, and the growing cow trade created a surplus of milk.
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