Assessment of the degree of rancidity on reused oils in university cafeterias,and public awareness

In this study, reused sunflower cooking oil was investigated for rancidity. Three student cafeterias at the University of Dodoma (UDOM) were used for this particular study. Oil samples were analyzed at the University of Dodoma laboratories. Results showed that all parameters were beyond permissible limits by WHO/FAO standards. Acid values ranged between 0.841 and 4.319 mg KOH/g oil, which is beyond the allowable limits by WHO/FAO (0.6 mg KOH/g oil). Peroxide values were found to be 19.5 mill eq O₂/kg oil (minimum), and 62 mill eq O₂/kg oil (maximum), which are both above the recommended limits by WHO/FAO (10 mill eq O₂/kg oil). Iodine values were found to be from 102.87 to 48.26-g I₂/100 g oil, and were all beyond the recommended limits by WHO/FAO, of between 118- and 141-g I₂/100 g oil. The study has further revealed that the number of customers that are saved by the three cafeterias exceeds the capacity of the cafeterias. This study also found out that many students (almost 74%) are not aware on general knowledge about rancidity, including health effects of using rancid oils. It is therefore recommended to the national regulatory authorities to formulate strict regulations to guide and control oil rancidity.