Ayu, Dewi FortunaAli, AkhyarSulaiman, Rudianda2016-09-292016-09-292016-09-29978-979-792-217-4http://repository.unri.ac.id/xmlui/handle/123456789/8675-The objective of this research was to evaluate the quality of the solid soap made from used cooking oil hawker food located in Tampan Subdistrict, City of Pekanbaru, through the addition of several doses of sodium hydroxide and foaming time. The research conducted from July to September 2009, at Laboratory Analysis and Processing of Agricultural Crops, Agricultural Faculty, University of Riau. The research experiments carried out by using a Factorial Randomized Block Design (RAK) with 3 repetitions. The first factor was the concentration of NaOH 32% (K) and the second factor was the length of foaming time. The observed parameters were water content, free fatty acid, pH, foam test, irritation test, and organoleptic test included color, aroma, and texture. The research results showed that the differencess concentration of sodium hydroxide influenced water content, free fatty acids, pH, aroma and texture, while the foaming time and their interaction influenced aroma and texture soap. Compared with SNI 06-3532-1994, water content and free fatty acid meet the quality standard of soap bar (SNI 06-3532-1994). Treatment K2W2 (NaOH 60 ml with 45 minutes) showed the best solid soap from used cooking oil.en-USsolid soapsodium hydroxidefoaming timefree fatty acidUR-Scientific Work Lecturer