Characterization of liquid soap from castor oil (Ricinus communis) with the addition of white tea extracts

Abstract

Soap is needed by all people to keep their bodies clean and healthy. Castor oil is one of the concerning plant oil that is produced from the kernel of castor plant that has the ingredients of ricinoleic acid and could make our skin become smooth. White tea contains polyphenol as the main ingredient. This research aimed to determine the quality of castor oil-based liquid soap based on SNI. The method used in this research was laboratory experimental using descriptive analysis and correlation-regression analysis. The treatments were the addition of white tea extract with 1% (v/v) concentration in amount of 0% (w/v), 0.5% (w/v), 1% (w/v), 1.5% (w/v), and 2% (w/v) out of 300 grams soap basis. The observation for liquid soaps included specific weight test, pH value test, total plate count test, organoleptic test, and antibacterial test. The analysis result showed that every formula complies with the requirement based on SNI 06–4085–1996 of liquid soap. The best soap product based on panelist preference from organoleptic test and the antibacterial test was liquid soap E with inhibition zone in the amount of 15.810 mm that is classified as a strong inhibition, specific weight of 1.0350 g/g, pH value of 9.653, and total plate count of 0.5 x 105 colonies/g.