0536 Extraction of phospholipids from procream using supercritical carbon dioxide and ethanol as a modifier.

Procream is a co-product obtained during manufacture of whey protein isolate. It mainly contains whey proteins (63%–72%), fat (12–20%), and approximately 20% of phospholipids (PLs) in total fat. The interest in PLs as functional ingredients is increasing in recent years. PLs affect several cell functions, such as growth, molecular transport system, memory processing, stress responses, and central nervous system myelination. Neutral lipids can be successfully extracted using supercritical carbon dioxide (SCO2). However, the solubility of PLs is limited in SCO2 and therefore a modifier such as ethanol is often needed to increase the solubility of PLs. The objective of present study was to use SCO2 and ethanol as a modifier to extract PLs from procream. For this purpose, the central composite rotatable design based on response surface methodology was used to optimize extraction conditions. The pH of procream (4-8) and extraction pressure (300–550 bar) were used as independent factors. The CO2 flow rate (5 mL/min), extraction time (1 h), and ethanol flow rate (0.033 mL/min) were kept constant. The extractions were performed in a supercritical extraction system supplied by Applied Separations Inc., PA. Procream was procured from a commercial manufacturer and stored at −20°C until use. A two-step extraction process was followed. In the first step, 10 g of procream was mixed with glass beads in the ratio 1:1 (v:v) and placed in the extraction vessel. Neat supercritical CO2 was allowed to pass through the extraction vessel to remove all the neutral lipids. In the second step, SCO2 and ethanol as a modifier was used to extract phospholipids. The remaining lipids from spent solids after the second extraction were extracted using the solvent extraction method. All the lipid fractions were analyzed by high performance lipid chromatography (HPLC) with kinetexTM HILIC (150 × 4.6mm, 5 µm) column. The amount of lipids extracted from after the second stage was significantly (P < 0.05) affected by pH of procream. However, pressure was found be not significant (P > 0.05). Only Sphingomyelin was found in the lipid fractions obtained after the second extraction step and it was found to be at higher concentrations at pH 7.4. On the other hand, phosphatidylcholine and phosphatidylethanolamine were not detected in lipids obtained after second extraction. Ethanol as a modifier was not able to improve the solubility of phospholipids in SCO2.