Ask any member of my generation what they remember most about train travel growing up, and there’s a better than even chance it’ll be the smell.

Chinese trains in the 1980s, ’90s, and ’00s were a rich olfactory experience. In those days before high-speed rail, trains were crowded, cramped, and slow. A train from Beijing to Shanghai might take anywhere from 10 to 20 hours, and passengers spent most of that time eating, sleeping, and sweating.

By the end of the journey, each car had an unforgettable aroma all its own. But the most ubiquitous smell belonged to the instant noodle sauce packets that passengers consumed in place of the more expensive food sold in the train’s dining car. A heady mix of beef paste, salt, and MSG — there was a reason the leading instant noodle manufacturer Master Kong marketed itself as “fragrance and taste you could see.” That heavy scent, combined with the smells emanating from the snack car, the sweat of other passengers, and the stench of the on-board bathrooms, created an instantly recognizable “smellscape.”

Not every train smelled the same, of course. In the slow train era, platforms and even the stations themselves were open spaces. Vendors hawked their wares to passengers through the open windows of cars. As a train passed through different cities, it would accumulate new flavors and scents, from the fatty, burger-style roujiamo of the northwest to the pungent, spicy rice noodles of the southwest.

In a sense, the smell of the train was the smell of openness, of urbanization and social mobility. Loosened restrictions on population movement in the 1980s and ’90s spurred a mass migration of labor from the interior to the coast. This new class of workers brought their spice-heavy cuisine with them to China’s megacities — and returned with new, convenience-focused items like instant noodles.

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As elsewhere, mass-migration cross-pollinated China’s regional foodways, helping create the Chinese food we know today. The braised chicken thighs served on the Guangzhou-Kowloon route, for instance, became a symbol of Cantonese cooking despite their lack of connection to classic Cantonese cuisine.

An even more famous example predates the migration wave of the late 20th century: Dezhou braised chicken. Opened in the early 1900s, the Tianjin–Pukou railway connected the northern city of Tianjin to Nanjing near the Yangtze River Delta. Located at a key point along the line, the eastern city of Dezhou became an important waystation connecting northern and southern China, where large numbers of passengers arrived to rest, dine, or change trains. As one of the best-tasting — and most portable — meals in Dezhou cuisine, Dezhou braised chicken became a popular souvenir for travelers passing through the city.

The rise of high-speed rail in the late 2000s all but erased this connection between train travel and local cuisine. Shorter journeys rendered on-board meals unnecessary, and the new high-speed rail stations are both tightly monitored and far more standardized than their predecessors. Many smaller stops are skipped altogether. As they navigate nondescript stations and carriages full of solemn faces, passengers are learning new behavioral norms, like avoiding loud conversations or strong-smelling food.

Behind this shift is a larger trend toward gentrification in China: higher rent in cities, more upscale stores, cleaner streets, and more complex rules of conduct for the populace. The “smellscapes” of trains, with their strong connection to migrant culture, have been displaced by the rise of a growing, internationalized middle class. Likewise, braised beef instant noodles — once the first choice for many train travelers — have been relegated to an emergency stockpile item or a nostalgic treat. Why bother with Master Kong when you can grab McDonalds or Starbucks before boarding?

These changes aren’t necessarily bad. After all, instant noodles aren’t some nutritious delicacy, and the pungent smell of some foods can be unpleasant to the uninitiated. Today’s more closed-off stations are also safer, with fewer pickpockets, more sanitary food, and less risk of being scammed. As China’s go-go years fade into memory, people naturally crave safety, stability, and efficiency. The distinctive flavor of slow train travel is a memory they might look back upon fondly, but it’s not something they want to relive.

That said, we also need to be wary of falling into the trap of Chinese “quality” (suzhi) discourse, in which economic and social changes are condescendingly flattened into a linear “civilizing” process. The idea that China’s new, cleaner, less smelly stations and train cars represent an improvement in “civilization” is mistaken. They’re merely a reflection of the country’s ongoing process of social and economic change. From Dezhou braised chicken to instant noodles and McDonald’s, we are what we eat.

Wu Yachang also made a contribution to this article.

Translator: Katherine Tse; editor: Cai Yineng.

(Header image: A boy eats  instant noodles on a train from Ganzhou to Beijing, 2019. Ding Bo/VCG)