In order to have valid results from sensory experiments with pre-schoolers, there is a need to match the sensory test to the abilities of children. A new approach for sensitivity testing with 4- year olds was therefore developed to accommodate their abilities as well as to engage them in the task. Inspired by the principles of authenticity tests, a protocol was designed to induce an affective response to a paired comparison test. This protocol included a story with magical characters, and the children were asked to identify if water samples with different concentrations of diluted basic tastes were “magic” water or regular water. Water was labelled as “magic” to trigger an emotional response, not an analytical one, which is more dependent on the level of cognitive processing. A pre-test on sweet and sour tastes conducted with 32 preschool children in Autumn 2014 indicated that children were able to understand the procedure, were engaged in the test, and could differentiate water from “magic” water in the majority of comparisons. Based on this, a more comprehensive protocol was developed, including all basic tastes with four different dilutions each. Paired comparisons are used, each time pairing a glass of plain water to water with a basic taste. The first session investigates the children’s sensitivity for sweet (sucrose), sour (citric acid), and umami (glutamate) taste in water, successively. The second session examines sensitivity for salt (sodium), and bitter (quinine) taste in water. The protocol includes a retest to investigate the reliability of the procedure with a subset of the children. The study will be carried out in Spring 2015 with 135 children aged 4 years old from 15 kindergartens. Results on children’s performance and reliability in the sensitivity test will be presented. The children’s understanding of the test will be discussed in light of their response bias when labelling water as “magic”, using the response criterion B