F1ANNEX IIIDETERMINATION OF PEROXIDE VALUE
7.Procedure
The test must be carried out in diffuse daylight or in artificial light. Weigh in a glass scoop (4.1) or, failing this, in a flask (4.2), to the nearest 0,001 g, a mass of the sample in accordance with the following table, according to the expected peroxide value:
Expected peroxide value(meq) | Weight of test portion(g) |
|---|---|
0 to 12 | 5,0 to 2,0 |
12 to 20 | 2,0 to 1,2 |
20 to 30 | 1,2 to 0,8 |
30 to 50 | 0,8 to 0,5 |
50 to 90 | 0,5 to 0,3 |
Unstopper a flask (4.2) and introduce the glass scoop containing the test portion. Add 10 ml of chloroform (5.1). Dissolve the test portion rapidly by stirring. Add 15 ml of acetic acid (5.2), then 1 ml of potassium iodide solution (5.3). Insert the stopper quickly, shake for one minute, and leave for exactly five minutes away from the light at a temperature from 15 to 25 °C.
Add about 75 ml of distilled water. Titrate the liberated iodine with the sodium thiosulphate solution (5.4) shaking vigorously, using starch solution (5.5) as indicator.
Carry out two determinations on the same test sample.
Carry out simultaneously a blank test. If the result of the blank exceeds 0,05 ml of the 0,01 N sodium thiosulfate solution (5.4), replace the impure reagents.
Substituted by Commission Implementing Regulation (EU) 2016/1784 of 30 September 2016 amending Regulation (EEC) No 2568/91 on the characteristics of olive oil and olive-residue oil and on the relevant methods of analysis.