4. Conclusions
Preparation of O/W cosmetic emulsions with grapeseed oil and diluted white or red wine in the aqueous phase presents certain advantages, such as direct inclusion of natural antioxidants, aroma and colour compounds in the emulsions that could enhance their organoleptic characteristics. In this study, it was found that the optimum percentage of wine addition in the aqueous phase is 20% (v/v) for both a red Sangiovese and a white Muscat wine with mean alcoholic grade 12.5% (v/v). At low wine concentrations, all emulsions were rheologically stable for a period of at least two months. The absence of mould formation and other surface alterations when higher concentrations of red wine were used could be attributed to the wine's high content in phenolic compounds which have antioxidant capacity, including a sufficient concentration of p-OH-benzoic acid derivatives which could act as natural preservatives.
The use of mastic resin from Pistacia lentiscus var. Chia as additive in O/W cosmetic emulsions with grapeseed oil resulted in refined texture and odour of the emulsions prepared. The optimum percentage of addition was found to be 2% (w/v). In combination with diluted white or red wine in the aqueous phase, the mastic resin yielded emulsions with higher oil droplet diameters and lower viscosity values but it did not lead to phase separation of the two-phase systems. Further studies could investigate whether at the concentration added, the mastic resin imparts also antibacterial properties to the emulsions studied.