PMID- 14733489
OWN - NLM
STAT- MEDLINE
DCOM- 20040311
LR  - 20151119
IS  - 0021-8561 (Print)
IS  - 0021-8561 (Linking)
VI  - 52
IP  - 2
DP  - 2004 Jan 28
TI  - Kinetics of diglyceride formation and isomerization in virgin olive oils by 
      employing 31P NMR spectroscopy. Formulation of a quantitative measure to assess 
      olive oil storage history.
PG  - 157-64
AB  - Diacylglycerol isomers and free acidity were determined for five extra virgin 
      olive oils of different initial acidities by employing a facile (31)P NMR 
      methodology as a function of storage time and storage conditions. The kinetic 
      treatment of the hydrolysis of triacylglycerols (TGs) and the isomerization of 
      1,2-diacylglycerols (1,2-DGs) to 1,3-diacylglycerols (1,3-DGs) during storage of 
      18 months at ambient temperature in the dark and light and at 5 degrees C in the 
      dark showed that the isomerization is strongly dependent on the rate of the TGs 
      hydrolysis, the initial free acidity (H(0)) of the virgin olive oil samples, and 
      storage conditions. Although the time-evolution of the diacylglycerols (DGs) 
      depends on the TGs hydrolysis, the ratio D of the concentration of 1,2-DGs to the 
      total amount of DGs was found to be independent of this factor. From the kinetic 
      expression of the ratio D, a quantitative measure was formulated that allows the 
      estimation of the storage time or age of virgin olive oils. Application of this 
      quantitative measure to several olive oil samples of known and unknown storage 
      history resulted in a very good agreement with respect to the actual storage time 
      for up to 10-12 months of storage. For a longer storage period, where the 
      isomerization of DGs is close to its equilibrium state, the calculated age index 
      is only indicative.
FAU - Spyros, Apostolos
AU  - Spyros A
AD  - NMR Laboratory, Department of Chemistry, University of Crete, 71409 Iraklion, 
      Crete, Greece.
FAU - Philippidis, Angelos
AU  - Philippidis A
FAU - Dais, Photis
AU  - Dais P
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - J Agric Food Chem
JT  - Journal of agricultural and food chemistry
JID - 0374755
RN  - 0 (1,2-diacylglycerol)
RN  - 0 (Diglycerides)
RN  - 0 (Olive Oil)
RN  - 0 (Plant Oils)
SB  - IM
MH  - Diglycerides/analysis/*chemistry
MH  - *Food Preservation
MH  - Hydrogen-Ion Concentration
MH  - Hydrolysis
MH  - Isomerism
MH  - Light
MH  - *Magnetic Resonance Spectroscopy
MH  - Olive Oil
MH  - Plant Oils/*chemistry
MH  - Time Factors
EDAT- 2004/01/22 05:00
MHDA- 2004/03/12 05:00
CRDT- 2004/01/22 05:00
PHST- 2004/01/22 05:00 [pubmed]
PHST- 2004/03/12 05:00 [medline]
PHST- 2004/01/22 05:00 [entrez]
AID - 10.1021/jf030586j [doi]
PST - ppublish
SO  - J Agric Food Chem. 2004 Jan 28;52(2):157-64. doi: 10.1021/jf030586j.