Olive Oil Analysis: K232, K270, ΔΚ
The impermeability to a particular “color” (wavelength) in the UV range is also called absorption.
Measured with a spectrometer and expressed as the “extinction coefficient” (K value).
The extinction coefficients K232 and K270 are used in practice to determine and record the proportion of oxidized constituents in an olive oil.
K232: conjugated dienes
Oxidation (see peroxide number) of olive oil produces so-called conjugated dienes in addition to peroxides. A K232 value of 0 is not possible, as well as the valuable ones.
Partially absorb components in this area. However, an elevated K232 value points to oxidation processes in olive oil, which may have the following causes:
- the olives are stored too long before being pressed
- during transport errors occur
- the temperature during extraction is too high (no cold pressing)
Extra virgin olive oil should have a K232 value in the range between 1.5 and 2.5.
K270: Oxidation-reduction products
As oxidation progresses, conjugated trienes also form. These are fatty acids with three contiguous double bonds, as well as oxidation-degradation products (aldehydes and ketones). The K270 value tells you how fresh the olive oil is!
The value is very low immediately after harvest and slowly increases over time. Old or blended with old oils olive oils have an increased K270 value. Aging (oxidation) is accelerated by sunlight or high temperatures. Olive oil should therefore always be stored cool and dark.
Extra virgin olive oil should have a K270 value in the range of 0.15 to 0.22
The delta K value (ΔΚ) is calculated from the values K266, K270 and K274 and serves as comparison value. An extra virgin olive oil typically always has a ΔΚ value of less than 0.01. Mixtures of different oil blends lead to high deviations in the ΔΚ value
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Pre-order & free shipping
Every year we only have a limited amount of extra virgin olive oil, black vegan olives, black olives and olive leaves, which are usually quickly sold out. Therefore, we offer our customers the pre-order mode including free shipping.
But of course you can without pre-ordering year-round get Olive Onkel’s best olive oil and olives. In this case, you will be forwarded to our online shop cooperation partners.