Then & NowHow war shaped Hongkongers’ tastes for foreign foods, and how tomatoes flourished under occupation

Sweet potatoes and tomatoes are among the many botanical introductions to maritime Asia to have resulted from the 16th-century Portuguese voyages of explora­tion. Along with sweetcorn, maize, guavas, papayas and, most notably, the chilli, these now commonplace food plants did not exist in this part of the world until Europeans introduced them.

Hardy and adaptable, they came into their own during the second world war, when imported foodstuffs were scarce.

“No rice to eat, eat sweet potatoes” was a common Cantonese refrain during the war years that is often quoted by elderly people nowadays. Widely grown as pig food, sweet potatoes remain unappealing for many who originally hailed from impoverished rural backgrounds. With the passage of time and rising prosperity, they felt that they could afford to eat something “better” and did not want dietary reminders of hard times and hostilities.

But, as 20th-century Chinese writer and philosopher Lin Yutang noted, patriotism is essentially nostalgia for the food of one’s childhood. Hong Kong’s burgeoning fondness for the humble sweet potato is one example of this simple truth and, roasted in charcoal, they are a popular street food, especially in the cooler months.

Also resurgent is a thin broth made of sweet potato chunks poached with old ginger and brown sugar, while in Taiwan, sweet potato leaves – commonly known as ground melon leaves – are popular as a healthy vegetable.

In early 1942, during the Japanese occu­pation of Hong Kong, canned American tomatoes were clandestinely obtained in Stanley Internment Camp. Whether the tins were sent in by friends or smuggled in on the black market is one of those minor historical details that were endlessly haggled over by ex-inmates, but whatever their provenance, these tomatoes were certainly eaten, and their residue – passed out “the other end” of those who consumed them – went into the communal compost.