Reduced levels of 1,2 DAG can indicate oxidation or adulteration with refined olive oil.
Diacylglycerols (DAGs) are lipid compounds that are found at different levels in fresh and refined olive oil.
Fresh olive oil contains a high proportion of 1,2-DAG’s and refined olive oil contains a higher proportion of 1,3-DAG’s.
During breakdown a greater proportion of 1,3-DAG’s are formed.
According to the Australian Olive Oil Association, the percentage of 1,2-DAG’s should be greater than 40% and a higher percentage indicates fresher oil. Determined with gas chromatography (DGF method C-VI 16(06) – ISO 29822:2009)