title: Rapid determination of cholesterol in milk containing emulsified foods.
abstract: In this study, a rapid and easy sample preparation method that involved no-heating saponification and dSPE (dispersive solid phase extraction) clean-up was developed to determine the level of cholesterol in milk containing emulsified foods (infant formula, baby food, cheese). The developed method utilised high performance liquid chromatography with an ultraviolet detector (HPLC-UVD) as a separation instrument. The optimum extraction conditions were determined as 10 mL isopropyl alcohol with 8.0 g (NH(4))(2)SO(4) per 1g sample, and saponification was achieved using 25mg KOH, 1.6g NaCl and 100mg of a silica based NH(2). Cholesterol levels determined using CRMs (NIST SRM 1849 and 1544) were in the range of the certificated value and the recovery test using spiked materials ranged from 94.34% to 102.34% with a RSD of 0.63-4.10%. This method enables the accurate determination of cholesterol with reduced sample preparation time.
authors.affiliation: Food Safety Center, Research and Development Institute, Namyang Dairy Co., Ltd., Gongju 314-914, Republic of Korea.
authors.forename: Jang-Hyuk
authors.initials: JH
authors.lastname: Ahn
authors.forename: In-Seek
authors.initials: IS
authors.lastname: Jeong
authors.forename: Byung-Man
authors.initials: BM
authors.lastname: Kwak
authors.forename: Donggil
authors.initials: D
authors.lastname: Leem
authors.forename: Taehyung
authors.initials: T
authors.lastname: Yoon
authors.forename: Changyong
authors.initials: C
authors.lastname: Yoon
authors.forename: Jayoung
authors.initials: J
authors.lastname: Jeong
authors.forename: Jung-Min
authors.initials: JM
authors.lastname: Park
authors.forename: Jin-Man
authors.initials: JM
authors.lastname: Kim
mesh_terms: D000818:Animals; D002417:Cattle; D002784:Cholesterol / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D002853:Chromatography, Liquid; D007225:Infant Food / Q000032:analysis*; D041943:Infant Formula / Q000737:chemistry*; D008892:Milk / Q000737:chemistry*; D052616:Solid Phase Extraction / Q000379:methods*
chemical_list: D002784:Cholesterol