Oil fractionation processes involve the crystallization of the most saturated triacylglycerols (TAGs) before separating the liquid phase. This can be done with or without the addition of solvents. The crystallization of TAGs is heavily influenced by the distribution of saturated fatty acids within them. Commonly, palm, palm kernel, or coconut oils undergo this process, which typically exhibit an asymmetrical distribution of saturated fatty acids in their TAG molecules, with some being present at the sn-2 position.
However, new high stearic oils derived from sunflower can also be fractionated. Unlike tropical fats, these oils have saturated fatty acids that tend to occupy the outer sn-1 and sn-3 positions of the TAGs. The distribution of fatty acids can be altered by chemical or enzymatic interesterification. In this study, we examined the effect of saturated fatty acid distribution on the fractionation of high oleic-high stearic (HOHS) sunflower oil. Specifically, we focused on how it impacted the operational temperature and the melting characteristics of the resulting stearins. By employing oil interesterification, the fractionation performance was improved, resulting in stearins with a higher solid fat content. Additionally, the temperature range for fractionation was expanded. These findings were successfully replicated at a pilot plant scale.