The Influence of WPC 80 Additive on the Stability of Water-In-Oil Emulsions

The effect of 0, 1.5, 5, 10 and 15 (g 100 g^-1 of emulsion) WPC 80 additive (80% whey protein concentrate) on the pH, physical, oxidative and microbiological stability of the water-in-oil emulsion was studied during 16-week storage at ~20°C at 4-week intervals. All determined features were significantly affected by the supplementation. The most beneficial as regards storage stability was the emulsion with 5% of WPC 80. This treatment was the most resistant to oxidative changes showing low increase of the concentration of conjugated diene hydroperoxides (from 0.92 to 1.04 mg g^-1) and of the thiobarbituric acid reactive substances (from 0.83 to 1.37 mg malondialdehyde g^-1) as well as only slight increment (by 0.47 log CFU g^-1) of the microorganisms number during storage. Thus, the results of the present study revealed that whey proteins can be applied in the proper amount to produce cosmetic emulsions composed of natural ingredients and with reasonable storage stability.