A crumpled instant-noodle bowl ground into the mud is an unlikely symbol of economic vitality. But during China's boom years those bowls were as ubiquitous around Chinese construction sites as the high-rise cranes above them.

That was no accident. For millions of Chinese workers, instant noodles were the convenient meal of choice, available for a few cents in every commissary and convenience store. And China's instant-noodle makers prospered. Between 2003 and 2008, annual instant-noodle sales expanded to $7.1 billion from $4.2 billion.

But just as China's economy has slowed, so too has its appetite for instant noodles. Last month, Tingyi, China's biggest noodle maker, was removed as a component of Hong Kong's Hang Seng Index after seeing its noodle profits drop 60 percent. China's instant-noodle sales are down 6.75 percent this year, the fourth consecutive year of decline.