title: The influence of temperature and pressure factors in supercritical fluid extraction for optimizing nonpolar lipid extraction from buttermilk powder.
abstract: The milk fat globule membrane, readily available in buttermilk, contains complex lipids claimed to be beneficial to humans. Phospholipids, including sphingolipids, exhibit antioxidative, anticarcinogenic, and antiatherogenic properties and have essential roles in numerous cell functions. Microfiltration coupled with supercritical fluid extraction (SFE) may provide a method for removing triacylglycerols while concentrating these nutritionally valuable lipids into a novel ingredient. Therefore, SFE as a method for phospholipid concentration needs to be optimized for triacylglycerol removal in buttermilk. The SFE conditions were assessed using a general full factorial design; the experimental factors were pressure (15, 25, and 35 MPa) and temperature (40, 50, and 60 degrees C). Particularly interesting is that only triacylglycerols were removed from buttermilk powder. Little to no protein loss or aggregation was observed compared with the untreated buttermilk powder. Calculated theoretical values showed a linear increase for lipid solubility as pressure, temperature, or both were increased; however, experimental values showed nonlinearity, as an effect of temperature. In addition, the particular SFE parameters of 35 MPa and 50 degrees C displayed enhanced extraction efficiency (70% total lipid reduction).
authors.affiliation: Department of Food Science and Technology, Oregon State University, Corvallis 97330, USA. rjimenez@calpoly.edu
authors.forename: A J
authors.initials: AJ
authors.lastname: Spence
authors.forename: R
authors.initials: R
authors.lastname: Jimenez-Flores
authors.forename: M
authors.initials: M
authors.lastname: Qian
authors.forename: L
authors.initials: L
authors.lastname: Goddik
mesh_terms: D025924:Chromatography, Supercritical Fluid; D043302:Cultured Milk Products / Q000737:chemistry*; D005524:Food Technology / Q000379:methods*; D008055:Lipids / Q000737:chemistry*; D011208:Powders / Q000737:chemistry*; D011312:Pressure; D012995:Solubility; D013696:Temperature
chemical_list: D008055:Lipids; D011208:Powders