Your browser does not support JavaScript!

Home    Collections    Type of Work    Post-graduate theses  

Post-graduate theses

Current Record: 4797 of 6472

Back to Results Previous page
Next page
Add to Basket
[Add to Basket]
Identifier 000408023
Title Μεταβολομική ανάλυση κρητικών λευκών τυριών άλμης με τη φασματοσκοπία πυρηνικού μαγνητικού συντονισμού NMR
Author Μαρκάκης Γιώργος Ι.
Thesis advisor Σπύρος, Απόστολος
Reviewer Μήλιος, Κωνσταντίνος
Περγαντής, Σπυρίδων
Abstract The main objective of the present study is the development of an analytical methodology for the determination of the metabolite and lipid profile of white brine cheeses by combining NMR spectroscopy and chemometrics. This methodology was then used to examine the authenticity of Protected Designation of Origin feta cheese. For the purpose of this study, feta cheese was compared to other Greek white brine cheeses. The white cheese samples that were analyzed originate from cheese producers that are operating in different regions of Greece. The types of analyzed white cheeses were feta, white cheese made from sheep’s and goat’s milk and white cheese made from cow's milk. NMR spectroscopy was used to detect and quantify the chemical compounds present inwhite brine cheese. The quantified compounds include amino acids (alanine, asparagine, valine, glycine, isoleucine, leucine, lysine, methionine, tyramine, tyrosyni, phenylalanine), organic acids (lactic, succinic, citric, butyric, gamma-aminobutyric, formate, acetate, 3-hydroxybutyrate), sugars (lactose, galactose, glucose), fatty acids (linoleic, linolenic, diglycerides, triglycerides, butyrate, caproleic, cholesterol) and other compounds (glycerol, choline, uracil). Two sequential sample pretreatment experimental protocols, using solvents of different polarity, were followed in order to perform the separate analysis of polar and apolar fraction of white cheese. Water was used as a solvent for the isolation of amino acids, organic acids, sugars and other low molecular weight organic compounds,while chloroform was used for the isolation of fatty acids and lipid profiling of cheese. The quantitative metabolic profile and the 1Η NMR spectra of the white cheese samples, in combination with appropriate multivariate statistical analysis methods were used as effective tools for the development of metabolomics models which can separate feta samples from other white cheeses according to the type of milk (sheep - cow) and the type of cheese (feta cheese - white cheese). With the use of the aforementioned models, additionally, the metabolites and the NMR spectral regions that are more effective in successful separating white brine cheese samples according to milk type and production type were obtained.
Language Greek
Subject Feta
Metabolomics
NMR Spectroscopy
White brine cheese
Λευκό τυρί
Φέτα
Φασματοσκοπία NMR
Issue date 2017-03-17
Collection   School/Department--School of Sciences and Engineering--Department of Chemistry--Post-graduate theses
  Type of Work--Post-graduate theses
Permanent Link https://elocus.lib.uoc.gr//dlib/e/4/f/metadata-dlib-1491300466-336363-4380.tkl Bookmark and Share
Views 244

Digital Documents
No preview available

Download document
View document
Views : 17