Abstract:
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
