Researchers compared the properties and fatty acid composition of regular palm oil, waste palm oil from frying fish and sausage, and waste palm oil turned into biodiesel. They found that the ratio of saturated to unsaturated fatty acids changed depending on how the oil was used and processed. Waste palm oil had more saturated fats compared to regular palm oil, likely due to repeated heating and cooling during frying and the biodiesel conversion process. This study shows how the way we use and recycle palm oil can affect its chemical makeup and properties.