In recent years luosifen have grown in popularity, even though you could not say they had taken off across the country. But then came COVID-19 and a greater reliance of hundreds of millions of Chinese on online shopping over the past six months, and the renown－or notoriety－of luosifen, rocketed. LIANG XIASHUN/ZHANG YANG/LI BIN/FOR CHINA DAILY

"The result has been good business traffic and exposure. Because of being unable to go out for dinner during the epidemic and because of a lack of foodstuffs, instant food has become a popular necessity. Coupled with the catalytic push of internet celebrities, the sales of snail noodles have ushered in explosive growth, and hundreds of thousands of searches have been posted on Weibo and TikTok."

In February the value of sales of snail noodles on the internet shopping platform Taobao exceeded 390 million yuan. Since then, monthly sales have more than doubled compared with the corresponding period last year, the Taobao Foodstuffs Big Data Report says. Ele.me, one of China's major online food delivery services, says take-away orders for luosifen have risen 58 percent after Feb 25.

No matter what manufacturer or brand of snail noodles you come across, a distinct smell is destined to hit your soul, the progenitor of that smell being sour bamboo shoots.

In humid Guangxi sourness is integral to local food. In addition, because bamboo is abundant in the region, and it is difficult to keep bamboo shoots fresh, sour bamboo shoots have naturally become the local staple side dish, one that depends on fermentation to prolong its usefulness.