Writing in the journal Food Quality and Preference, Dr Elder said he isn't sure why eating noisily has such a noticeable effect.
It may be that the act reminds us of how much we are eating. It is also possible we tire of eating more quickly when it is a louder experience.
Whatever the reason, it could help to explain why we tend to munch mindlessly in front of the TV or at the cinema - and means that people could lose more weight simply by eating in silence.
Dr Elder said: "When you mask the sound of consumption, like when you watch TV while eating, it may cause you to eat more than you would normally."
But while the crunch factor could lead to us eating less, we may enjoy the food more.
Previous British research has shown how crisp foods trigger the brain's pleasure centres, with the sound of biting into an apple the most enjoyable.
The makers of Magnum ice cream learned this lesson the hard way.
In response to criticism that the chocolate coating was too brittle, they produced a softer one - only to be told by customers they missed the cracking sound of the original. A return to the first formulation soon followed.