## 2 Materials and Methods  
### Compositions and Characteristics of the Formulations  
Four simple O/W emulsions, with as few ingredients as possible and without any active ingredient, were prepared. The compositions described in Table 1 contained a low dose of (C14-C22 alcohols (and) C12-C20 alkyl glucoside) emulsifier (Figure 1). The final ingredient retained the excess fatty alcohol used in the glycosylation reaction. Keeping formulations as simple as possible was necessary to understand the contribution of ingredients. The emulsion structure was adapted to be as close as possible to formulation habits and consumer expectations in the geographical region in which the product was evaluated. The skin feel was tailored to be more or less light depending on the climate by choosing a suitable oily phase (nature of oils/emollients, and dosage) [23; 24; 25; 26]. To restrict the variations and number of ingredients, local expert formulators were requested to swap between 4 oils: one mixed decanoyl and octanoyl glycerides (INCI: caprylic/capric triglyceride), one linear ester (INCI: coco-caprylate/caprate), two branched esters (isononyl isononanoate and cetearyl ethylhexanoate). As the purpose was to determine whether C12-C20 glucolipid emulsifier would allow the composition to be varied while providing a significant moisturizing effect, oils without known occlusive effect were preferred to minimize their interference, assuming that if versatility could be demonstrated on these oils, it would be even more true with occlusive \"heavier\" oily phases. Esters with different fatty chain lengths were proposed to modulate the skin feel based on the previous sensory ranking of expert panelists (medium light: cetearyl ethylhexanoate, ester of C16-C18 fatty alcohol and branched C8 fatty acid; light: coco-caprylate/caprate, ester of C12-C16 fatty alcohol and C8-C10 fatty acid: very light: isononyl isonononanoate, ester of branched C9 fatty alcohol and branched C9 fatty acid). Caprylic/capric triglyceride was proposed as one of the most frequently used emollients in skin care formulas worldwide but was not used alone due to its lack of glide and too rich skin feel, as reported by the formulators. For the study in France, cetearyl ethylhexanoate alone was chosen for its balanced medium light skin feel and good spreading properties (E1, Table 1). Caprylic/capric triglyceride was basically chosen for its popularity in Brazil and India. Both Brazil and India chose to combine it with coco-caprylate/caprate to improve spreading. In Brazil, isononyl isononaoate was also added at the minimum concentration to speed-up the absorption time (E2, Table 1; caprylic/capric triglyceride and coco-caprylate/caprate were used at a higher dosage than isononyl isononaoate due to their natural origin). For India, the formulator preferred to keep the 2 oils of natural origin and reduced the total content in the oily phase to lighten the skin feel (E3, Table 1). The highest concentration of oily phase, adapted to a lower temperature, was chosen for the study in France. Oily phase content was reduced for warmer climates to avoid tackiness and oily sensation (Figure A1 in Appendix A visualizes the formulation adaptations according to the targeted geographical area). For the study in Mauritius, as less interest was expressed in caprylic/capric triglyceride, it was decided to keep a simple bio-based emulsion with a light ester with good spreading properties: coco-caprylate/caprate (E3, Table 1). Skin sensory profile was not assessed but, depending on the oil phase composition, the skin feel was expected to be from medium light to very light (opposite to rich) with the following relative positioning on the \"light\" criterion: E4 (10% light ester) > E3 (10% combination of medium light triglyceride with very light ester) > E2 (12% combination of medium light triglyceride with light esters) > E1 (20% medium light ester based on a longer fatty chain).