Analysis of selected quality parameters for edible sesame oil samples available in Jaffna district

Abstract

Parameters such as free fatty acid value, saponification value, peroxide value, refractive index and color can be used as quality indicators in the determination of sesame oil quality which is extracted from the seeds of Sesamum indicum. This study was conducted to measure the above quality parameters of locally produced edible sesame oil available in Jaffna district. Sesame oil samples were collected from ten randomly selected processing centers during two different production time period and replicate values were obtained and mean values were taken into consideration. All the laboratory analyses for sesame oils were done according to the Sri Lanka Standard (SLS) 313 procedure and the results were compared with Sri Lanka Standard 23L:201,3. According to the SLS 231,:201,3, the saponification value varied in the range of 1BB-193, refractive index at 40'C ranges 1.465-1.469, color less than 20, free fatty acid (as oleic) value less than 3 and peroxide value less than 10 can be an indication for good quality sesame oil. The results show that the mean value of free fatty acids and color from ten processing centers met the standard. Seven out of ten processing centers were within the range of specified saponification value. The mean value of peroxide value and refractive index of oils from nine processing centers were within the standard value. Therefore, based on the results of this study it can be decided they can be used for edible purpose with some improved process.