Abstract:
The free alkali present in the toilet soaps disrupt the natural pH of the skin, leading to skin dryness. Hence this study was conducted to produce a natural liquid soap with lesser free alkali content using soapberry (Sapindus mukorossi) drupes, rock salt, cold pressed virgin coconut oil (Cocos nucifera) and palmyrah (Borassus flabellifer) fruit pulp which contains oil-soluble carotenoids capable of rejuvenating our skin. Carotenoids from palmyrah fruit pulp were extracted using 80 %( v/v) aqueous glycerol and cold pressed virgin coconut
oil in 2:1 (v/v) ratio. Three different formulations were established. The soap formulation containing rock salt to replace one third of KOH contained significantly less free alkali (g/L) (0.75± 0.05) than the formulation containing no rock salt (1.34 ± 0.28). Meanwhile the soap without carotenoids had significantly lower fatty matter (%) and higher free alkali than the formulation containing carotenoids. Carotenoids and rock salt reduce the drying effect of soaps.
