The antioxidant capacity of polyphenols plays an important role in the stability of olive oil, as there is a correlation between the amount of total polyphenols and resistance to oxidation over time.
The polyphenols have a protective action not only on oil but also on cells of the human body because they oppose the negative effects of free radicals.
The amount of polyphenols decreases during oil extraction so the test can be used to optimize the processing.
The oxidative stability index (OSI) of olive oil is directly proportional to the antioxidant capacity (polyphenols). It is calculated on the basis of the comparison between CDR method and AOCS official method Cd 12b-92 (Rancimat), performed by Minerva SA e Asteriadis SA in collaboration with the University of Athens, which estimates the time of induction, expressed in hours.
Analyzers to test polyphenols and Oil Stability Index (OSI) in Olive Oil
You can determine the value of the polyphenols/OSI in olive oil with different systems of CDR FoodLab® range : CDR OxiTester for analysis of olive oil in oil mill, CDR FoodLab® for analysis of Vegetable and animal fats and oils
| CDR OXITESTER | CDR FOODLAB® | |
|---|---|---|
| Matrici alimentari | Olive Oil | Vegetable and animal fats and oils |
| Analisi | Free Fatty Acids (FFA) Peroxide Value (PV) Polyphenols/OSI K270 |
Free Fatty Acids (FFA) p-Anisidine Value Peroxide Value (PV) Soaps Polyphenols/OSI in olive oil Iodine Value (IV) in palm oil |
Method
Testing time: 5 minutes – 30 Tests/Hour
It is possible to carry out several test sessions with a maximum of 16 samples.
Principle of the test
The polyphenols, in contact with a chromogenous compound in an alcoholic solution, are oxidized and decrease the color of the compound. The decreasing of color, read at 505 nm, is directly proportional to the concentration of polyphenols in the sample, expressed as mg / kg of tyrosol.
Calibration Curve / Correlation Data
The new Total Polyphenols (Biophenols) analysis used by the CDR OxiTester has been calibrated with the reference method IOC / T.20 / Doc. n. 29: 2009, by the Commodity Chemical Laboratory of Chamber of Commerce of Florence, Italy. They confirmed that the results of the Total Polyphenols of olive oil analysis, obtained with the CDR OxiTester, are compliant with the reference method.
CDR Oxitester method shows a very good correlation with OIC (International Olive Council) method.
Reagent test Kits
The reagents are packaged in foil pouches containing 10 tubes useful to perform 10 analyses.
This is the minimum package that allows the use of CDR systems even to those who need to make a few analyses, thus not wasting reagents.
There are also boxes of 100 tests, however, packaged in 10 bags of 10 tubes containing the reagent.
Code. 300478: 10 tests
Code. 300475 : 100 tests (10 packages of 10 tests)
The reagents have a shelf-life of 12 months.
Sample Handling
Use oil as is. (olive oil or vegetable oil)
Measuring Range
| Measuring range | Resolution | Repeatability |
|---|---|---|
| Total Polyphenols (Biophenols) | 1 mg/Kg tyrosol | 10 mg/Kg tyrosol |
| Oil Stability Index (OSI) | 0.1 h | 0.3 h |
