"We want young people to eat many apples and came up with the idea of portable apples for your bags," said Hwang Hye-sung, a researcher at South Korea's Rural Development Administration, who called it a "do-it-yourself bad breath treatment."

Apples help freshen breath naturally and remove pieces of food stuck in the teeth, but the ping-pong ball-sized apple would be easier to carry around, and far less filling to gulp at a critical moment. "We can mass produce the species with stronger functions that control food odors in as few as two years," Hwang added. But potential consumers were skeptical, noting that sudden chomping down on an apple might not do much for romance.

"I'm afraid this could damage the mood, unless you are sure you will kiss," said Kim Min-jung, a 28-year-old office worker.