# Commission Regulation (EEC) No 2568/91 of 11 July 1991 on the characteristics of olive oil and olive-residue oil and on the relevant methods of analysis, Division 5.3

Extent: E+W+S+N.I.

If necessary, correct the baseline (220-290 nm) with solvent in both quartz cells (sample and reference), then fill the sample quartz cell with the test solution and measure the extinctions at 232, 268 or 270 nm against the solvent used as a reference.
The extinction values recorded must lie within the range 0,1 to 0,8 or within the range of linearity of the spectrophotometer which should be verified. If not, the measurements must be repeated using more concentrated or more dilute solutions as appropriate.

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Source: https://www.legislation.gov.uk/eur/1991/2568/annex/IX/division/5/division/5.3 (the official version)
Page: https://openlegislation.uk/eu-regulation-1991-2568/annex-IX/division-5/division-5.3
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.