Latest research shows there are actually scientific reasons why children may be more sensitive to bitter tastes or have an especially strong sweet tooth. Researchers found variation in a taste receptor gene influences taste sensitivity in both children and adults. Age and culture also contribute to taste preferences and sometimes have a greater impact.
For the study researchers compared taste sensitivity and food-related behaviors across three genotypes of a gene that encodes a taste receptor responsive to bitter taste. They studied 143 children and their mothers, taking cheek swab samples and participants were divided into three groups based on their genotype of varying sensitivities to bitterness.
Results showed while more than half of participants with bitter-sensitive sites on their genotype detected bitterness in a certain solution, only a few participants who had bitter-insensitive sites did. Children also tended to be more sensitive to bitter tastes than adults. Additionally, children with bitter-sensitive sites preferred sweeter solutions than children with bitter-insensitive sites. However, the same was not true in adults.
In conclusion researchers say race and ethnicity were found to be the strongest determinants in adults' sweet preferences , thus they say that the forces of experience and culture appear to have overridden the genetic effect.