Home
Resource
Development of new methods for analyzing lipid oxidation
PDF
PDF format is widely accepted and good for printing.
Plug-in required
PDF-1(5.55 MB)
Citation & Export
View Usage Statistics
Staff View

Citation & Export
Hide

Simple citation

Yao, Linhong. Development of new methods for analyzing lipid oxidation. Retrieved from https://doi.org/doi:10.7282/T35D8TPQ

Export

Click here for information about Citation Management Tools at Rutgers.

Statistics
Hide

Description

TitleDevelopment of new methods for analyzing lipid oxidation
NameYao, Linhong (author); Schaich, Karen M. (chair); HO, CHI-TANG (internal member); Hartman, Thomas G. (internal member); Johnston, David (outside member); Rutgers University; Graduate School - New Brunswick
Date Created2015
Other Date2015-05 (degree)
SubjectFood Science, Lipids--Oxidation, Solvent extraction
Extent1 online resource (xviii, 162 p. : ill.)
DescriptionThe basic reactions of lipid oxidation were first reported more than 50 years ago, yet accurate and reproducible measurement of lipid oxidation remains a serious problem and challenge for both industry and academia. This research addresses two critical issues in lipid oxidation measurements: 1) lack of extraction methods that do not induce adventitious oxidation or change existing oxidation products; 2) lack of sensitive reproducible methods for quantitating and identifying secondary non-volatile oxidation products such as carbonyls, core aldehydes in particular. This research aims to develop two reliable, sensitive and accurate methods for oxidation analyses: 1) a pressurized solvent extraction method that is efficient in removing lipid yet does not add to or destroy lipid oxidation products, and 2) an improved HPLC-DNPH assay to quantitate and identify soluble carbonyl oxidation products in individual lipid fractions. Baked pet food biscuits and dry extruded pet food kibbles were chosen as samples to conduct lipid extraction in pressurized accelerated solvent extractor (ASE) by adjusting a variety of factors such as temperature, sample particle size, polarity of extraction solvent, extraction static time and numbers of extraction cycles to investigate the effect of extraction conditions on lipid oxidation. Results showed extraction with two 15-minute cycles of chloroform:methanol at 40 C gave lipid yields of 75-100%, depending on the kibble. Lipid oxidation was minimal when temperature was limited to 40 C. Factors such as particle size, solvents and extraction static time and cycles could be combined and tailored to optimize extraction efficiency. Compared to traditional extraction methods, pressurized solvent extraction of lipids was significantly more efficient and induced less oxidation. A reverse phase HPLC-DNPH (2,4-dinitrophenylhydrazine) assay capable of quantitating and identifying carbonyls in all lipid classes was developed using an acetonitrile–isopropanol-water gradient and diode array detection at 360 nm. Optical response decreased with fatty acid chain length; quantitation was achieved using average slopes for three size ranges. The assay was specific for carbonyls and detected 6-50 g/L and accurately quantitated 20 g/L standard aldehydes. LC-MS/MS Q-TOF verified hydrazone structures. Monomer carbonyls and core aldehydes were distinguished and quantitated in oxidized Trilinolein, commercial oils, and lipid extracts.
NotePh.D.
NoteIncludes bibliographical references
Noteby Linhong Yao
Genretheses, ETD doctoral
Persistent URLhttps://doi.org/doi:10.7282/T35D8TPQ
Languageeng
CollectionGraduate School - New Brunswick Electronic Theses and Dissertations
Organization NameRutgers, The State University of New Jersey
RightsThe author owns the copyright to this work.
Version 8.5.5
Rutgers University Libraries - Copyright ©2024