Comparative study of lipase preparations for enzymatic degumming of sunflower oil

Introduction. Degumming is a crucial stage in the production of refined vegetable oil. Enzymatic degumming has been applied as a mean to improve process efficiency, and currently, many new lipase preparations are available. The present study aimed to assess the efficiency of their application on the degumming process of sunflower oil.Materials and methods. Enzyme preparations Lecitase (R) Ultra, Quara (R) Boost, and Quara Low P were received from Novozyme (Denmark). Phosphorus content in oil ash was detected photometrically. Acid, peroxide, and saponification values were determined by standard methods. Antioxidant properties of the oil were estimated based on 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity. Results and discussion. Enzymatic degumming of sunflower oil results in an increase in oil yield compared with water degumming. Degumming with Quara (R) Boost preparation results in 98% oil yield, which was 1.5% higher than in the case of water degumming. Using Lecitase (R) Ultra and Quara Low P increased oil yield by 1 and 0.5%, respectively, compared with water degumming. The phospholipid content decreased from 0.4% in crude oil to 0.2% after water degumming, meanwhile, the application of enzyme preparations Lecitase (R) Ultra and Quara Low P reduced the content of phospholipids to 0.08% and 0.06%, respectively. The lowest phospholipid content, 0.04%, was in the sunflower oil after degumming with phospholipase C (Quara (R) Boost), which corresponds to 16 mg of phosphorus per kg of oil. The saponification value of sunflower oil degummed with phospholipase C preparation proved the formation of diacylglycerols in oil, 191.5 mg KOH/g. The highest free fatty acid content in sunflower oil was after degumming with Lecitase (R) Ultra: the acid value increased from 0.86 mg KOH/g in crude oil to 2.7 mg KOH/g in degumming oil. However, Quara Low P preparation also has phospholipase A1 activity, so, the acid value decreased slightly compared with crude oil. Degumming with Quara (R) Boost preparation did not affect the free fatty acid content in sunflower oil, and the acid value was even lower than in the oil degummed with water. The peroxide value of sunflower oil was <1 meq O/kg after enzymatic degumming, meanwhile the peroxide value of sunflower oil after water degumming was 2.6 meq O/kg. All oil samples had a similar antioxidative capacity that was 30-36% of scavenged DPPH. radical.Conclusions. The most effective enzyme preparation for sunflower oil degumming was Quara (R) Boost with phospholipase C activity. Application of Quara (R) Boost results in the highest oil yield, the lowest content of phospholipids and free fatty acids, low peroxide value, and high antioxidant capacity of oil.