Significant sugar-reduction in dairy products targeted at children is possible 7 without affecting hedonic perception 8 9

21 The objective of the present study was to evaluate children's hedonic sensitivity to sugar 22 reduction in three dairy products: vanilla milk desserts, chocolate-flavored milk, and 23 vanilla yogurt. For each product, a regular sample and five samples with different 24 reduction in added-sugar content were formulated. The regular sample contained the 25 sugar content of commercial products available in the marketplace. The reduction in 26 added-sugar content ranged between 10.0 and 41.0%. A total of 126 children (8 to 13 27 years old) participated in the study. An A-not A test was used to evaluate children's 28 hedonic sensitivity to sugar reduction. Sugar reductions up to 27% in chocolate flavored 29 milk and vanilla yogurt, and up to 19% in vanilla milk desserts, did not cause significant 30 changes in children's hedonic reaction. These results confirm that sugar-reduction 31 strategies can be easily implemented in the dairy industry without significant risk of 32 affecting sample appreciation and market share. 33


Introduction 36
Sugar intake has been identified as one of the most important dietary factors for 37 childhood overweight and obesity (Newens & Walton, 2016;WHO, 2015). Children 38 frequently consume processed products with high added sugar concentration (Azaïs- a reduction in added sugar seems necessary to reduce children's sugar intake. 51 Sugar content of dairy products can be gradually reduced so that consumers get 52 used to lower sugar concentrations without noticing any differences ( Chocolate-flavored milk was prepared using UHT whole milk, 1% w/w alkaline 98 cocoa powder (Aryes, Montevideo, Uruguay), 0.08% w/w carrageenan, 0.05% v/w 99 vanilla and varying concentrations of sugar (Table1). Samples were prepared using a 100 Thermomix by adding the powdered ingredients to whole milk, previously heated at 70°C 101 for 3 min, and dispersed for 1min. The mixture was kept at 70°C for 4 min under constant 102 stirring. Then, vanilla was added to the mixture and stirred for 1 min. Finally, the samples 103 were cooled down to 20°C in ice water and placed in glass jars. Samples were stored for 104 24 h at 6-8°C until their evaluation. 105 106

Vanilla yogurt 107
Samples were prepared using plain skimmed yogurt (Conaprole, Uruguay), 0.4% 108 v/w vanilla flavoring and varying concentrations of powdered sugar (Table 1) images. First, an image of a reference apple was presented. Children were asked to 154 watch it carefully and to try to remember its characteristics. Then, the reference apple 155 image and a defective apple image were presented one by one. For each of the images, 156 they were asked to indicate if they liked the apple image as much as they liked the 157 reference apple image, using the response options "Yes", "No" or "I don't know". 158 159

Sample familiarization 160
Before the actual sample tasting, children had to complete a warm-up task for 161 sample familiarization. Children were presented with the reference sample, named 162 "secret formula". They were asked to try it and to remember its characteristics. Then, two 163 samples (again the reference and the warm-up sample) were presented. For each of the 164 samples, they were asked to indicate if they liked the sample as much as they liked the 165 reference sample using the response options "Yes", "No" or "I don't know". 166 167

Sample tasting 168
After completing the warm-up task, children were asked to taste the reference 169 sample again. Then, they were presented with six samples (the reference and the five 170 sugar-reduced samples, c.f. Table 1)

Results and Discussion 188
The present work aimed at providing insights for the design of sugar-reduction 189 strategies of dairy products targeted at children. For this purpose, children's sensitivity 190 to sugar reduction was studied, in three highly consumed dairy products, using the A-191 not-A test. Results from the familiarization step with apple images showed that children 192 understood the task: the percentage of children who reported liking the reference apple 193 (when it was presented blind) as much as the reference was higher than 80% across the 194 three sessions. 195 Table 2  Interestingly, hedonic sensitivity to sugar reduction was largely similar across the 216 three product categories. As shown in Table 2 Results from the present work suggest that added-sugar can be reduced up to 233 25% in dairy products targeted at children without affecting their hedonic perception. This 234 information is highly valuable for sensory scientists and food technologists and confirms 235 that sugar-reduction strategies can be swiftly implemented in the dairy industry without 236 significant risks of affecting market share. In this sense, these results stress the lack of 237 justification of the slow response of some dairy industries worldwide to reducing the 238 sugar content and sweet taste of their products targeted at children.  Notes: * Children answering "Don't know" were excluded from the analysis. The d' estimates of samples highlighted in bold are significantly different from 0.