The acid value of olive oil was determined by fully automatic potentiometric titration

I. Preface

Olive oil is directly cold-pressed from fresh olive fruits without heating or chemical treatment, thus retaining its natural nutrients. Olive oil is regarded as the most suitable oil for human consumption among all the oils discovered so far. It is hailed as liquid gold in the West and has excellent natural health benefits, beauty effects and ideal cooking uses.

This method employs fully automatic potentiometric titration to determine the acid value of olive oil. It features good repeatability and significant jumps, enabling accurate measurement of the acid value of the oil and providing a precise basis for oil product testing.

Ii. Instruments and Reagents

2.1 Instruments

JH-T7 fully automatic potentiometric titrator, PH composite electrode, analytical balance, etc

2.2. Reagents

Ether - isopropanol (1:1) solution, sodium hydroxide (0.1mol/L) standard solution.

Iii. Experimental Methods

3.1 Sample testing

Accurately transfer 20g of the oil sample into the titration cup, add 50ml of the ether - isopropanol (1:1) mixed solution, mix evenly, place the sample on the potentiometric titration stand, start stirring, insert the electrode and titration head, and after the potential stabilizes, titrate to the end point with sodium hydroxide (0.1mol/L) standard solution, and record the end titration volume. The parameters of the titrator are set as shown in Table 1

Jiahang Table 1 Titration Parameter Settings

3.3 Test Graph Example

Iv. Results and Discussion

4.1 Experimental Results

The experimental results are shown in Table 2

4.2、Conclusion

The acid value of olive oil tested in this test is 0.5739mgKOH/g. The data has good repeatability and the operation is safe and simple. It is a good choice for detecting acid value.

[1] GB 5009.227 National Food Safety Standard - Determination of Acid Value in Foods [S