Even when optimized for the puffiest corn, microwave popping gave about 10% less expansion than a hot plate, the team found.
The problem, says Karababa, is that microwaves heat the corn very quickly. Although the hot oil around the kernel ensures that virtually every kernel explodes, it also stops starch molecules in the corn from stretching out properly as they pop.
The work adds to 50 years of popcorn research into the best type of corn, water content and popping temperatures to make the best product. The results should be of interest to commercial producers who buy unpopped corn by weight, but sell the popped product by volume; for them, bigger popcorn means bigger profits.
The recipes may make business people happy. But will they be kind on the consumers' arteries?
'Popcorn itself is not that bad for you,' says dietician Catherine Collins from the British Dietetic Association. It's the flavourings we heap on it that count against our hearts and waistline, she says. 'In this study, they do use a lot of butter - it's probably enough to double the calorie count.'
I've always suspected that nuke ovens were a capitalist plot against the popcorn-loving masses. Now, at last, confirmation!