Which Tastes Sweeter, Candy or Jelly?
A Yonsei research team has proved that food hardness acts as a determinant of food preference.
Given the same sugar content, which of hard candy or soft jelly is felt to be sweeter? A study reported that preference for food with same taste may vary according to its hardness.
The research team led by Professor Seok Jun Moon(left) from the Department of Oral Biology at Yonsei University College of Dentistry recently published a study on the ‘clarification of the mutual relationship between food hardness and taste cognition’ on Nature Communications, a sister journal of Nature.
The research team analyzed the behavior of fruit flies (Drosophila melanogaster) to study signal transduction of mechanical senses (mechanosensory) on hardness and taste sense (chemosensory) and to find out which of hard food or soft food they preferred. With same hardness, flies were attracted to more sugary food, but as hardness increased, they moved to softer food, even if it was less sweet. With a large difference in sugar content (10 times), the flies moved to more sugary food, overcoming the difference in hardness (10 times).
The research team also demonstrated that as mechanosensory neurons in mouth part of Drosophila were activated, their degree of sensing sweetness decreased when presented with the same concentration of sugar. As the sugar concentration increased, their cognition of sugar increased, but when their tactile nerves were activated artificially, their cognition of the same concentration of sugar rapidly decreased.
According to Professor Moon, food hardness acted as a determinant of food preference through analyzing the behavior of fruit flies. Even with same sweetness, the mechanical stimulus of sensory nerves of the gustatory organ transmitted the information of food hardness to the brain to inhibit the signal transduction of the nerves sensing sweetness.
This study demonstrated the interactions between food hardness and taste for food preference through behavioral genetics and latest imaging technique.
Professor Hyuk-Jae Chang
Professor Sung-Joo Hwang
Professor Dae Hyun Lew