As she sunk her teeth into a tomato she'd grown at an organic farm in Kunshan, Jiangsu province, Shen Ye's mind raced back to when she sang with her grandfather in their countryside garden as a child.

It was as juicy and delicious as the ones her grandpa picked for her in their hometown of Anji county, Zhejiang province.

The 38-year-old has been working as a volunteer for the farm for the past three years. That's because, one day, she had a hangover.

Several years ago, Shen, who was a band manager for a rock music label in Beijing, yearned for the delicious tomatoes of her childhood after waking up in agony, following a night of heavy drinking.

She scoured supermarkets and grocers but was surprised to find that the megacity that is the national capital didn't have tomatoes like those she'd enjoyed as a little girl.

"They all look like tomatoes but don't taste like the real sweet-and-sour ones," she recalled.

She bought seeds online and tried to grow tomatoes on her apartment's balcony but failed. They only grew as big as cherry tomatoes and were soon eaten by birds.

She couldn't even find seeds to grow tomatoes like those from her childhood.

In 2014, Shen left the music industry to work for a farmers' market in Beijing. She was responsible for organizing local farmers to sell organic produce to urbanites.

"Even though I learned a lot about organic farming there, I was still separated from the land," she recalled.

"So, I considered moving to a smaller place where I could work in the fields to plant and harvest organic food."

She and her husband moved to Kunshan in 2019.

As a part-time volunteer, she goes to the farm several days a week and spends nearly a whole day there.

One of her jobs, which she believes is urgent, is to conserve the seeds of traditional crop varieties before they completely disappear from the world, such as the tomatoes she had as a kid.

Shen said most farmers now plant hybrid or transgenic seeds purchased from stores. These plants can't produce viable seeds, so farmers have to buy new ones every year.

Also, this kind of produce is usually less tasty since it needs to endure long periods in transportation or storage.

These market conditions are causing many heirloom seed varieties to disappear.

Consequently, some localized foods are vanishing, too, she explained.

For example, Kunshan's ancient town of Zhouzhuang used to be known for a popular pickled cabbage dish called apo cai. But there is no authentic apo cai now because the real thing was made from a traditional Chinese cabbage variety that nobody grows anymore.