• Journal of the Society of Cosmetic Scientists of Korea
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• v.44 no.2
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• pp.125-131
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• 2018

Ascorbic acid (Vitamin C) has been widely used in skin care formulations. Due to its remarkable effects on anti-oxidation, collagen biosynthesis and whitening, ascorbic acid is considered as an effectible anti-aging active ingredient. But, the instability problems of ascorbic acid in cosmetic formulation such as oxidation, browning and changes in smell is the difficult issue to be overcome for the application of high concentration of ascorbic acid. We tried to stabilize the ascorbic acid in non-aqueous liquid formulation that contains polyol solvent at first. The non-aqueous system was effectible to reduce oxidation. But, ascorbic acid was crystallized in the non-aqueous formulation at the low temperature below $5^{\circ}C$. We tried to develop way to stabilize the ascorbic acid in aqueous solutions to solve the crystallizing problem. In this study, we search the optimal ratio of antioxidant combination, such as zinc sulfate, glutathione and curcuma longa (turmeric) root extract. Formulations were stored at - $16^{\circ}C$, $5^{\circ}C$, $25^{\circ}C$, $40^{\circ}C$, $50^{\circ}C$ and cycle($5-40^{\circ}C$) (in incubator) for a period of eight weeks to investigate their stability. In the stability analysis, the test parameters consisted of color, scent, phase separation and sedimentation. Ascorbic acid stability was checked by HPLC analysis.