NEWS
06
2025
-
06
Determination of moisture content in soybean oil by volumetric method
I. Preface
Soybean oil is an oil extracted by pressing soybeans and is one of the commonly used cooking oils. As one of the commonly used edible oils, the quality of soybean oil directly affects the dietary health of consumers. In response, the state has formulated strict implementation standards to ensure the safety and health of consuming soybean oil. Among them, moisture is an important indicator in the detection requirements, which indicates that the moisture and volatile substances should not exceed 0.2% of the content. The moisture content was determined by the Karl Fischer volumetric method, which has good repeatability and can quickly and accurately measure the moisture content.
Ii. Instruments and Reagents
2.1 Instruments
JH-V5 Karl Fischer moisture titrator, analytical balance, etc
2.2 Reagents
Karl Fischer titrant, methanol - n-hexane (1:2).
Iii. Experimental Methods
3.1 Sample Testing
Through the liquid discharge device of the Karl Fischer moisture titrator, the residual liquid is removed. Then, 40mL of the solvent methanol-n-hexane (1:2) is added to the titration cup, with the solvent covering the electrode. After setting the parameters, the instrument starts the pre-titration. When the instrument is in standby mode, click on the system injection, open the rubber stopper of the feeding port, and select the injection volume according to the volume of titration solution consumed by the sample. Quickly add the sample, immediately cover the rubber stopper, click "Start Measurement", and use Karl Fischer. Titrate the titrant to the endpoint, input the sample weight, and calculate the moisture content of the sample.
The parameters of the titrator are set as shown in Table 1:
Table 1 Titration Parameter Settings
|
Stirring speed：35% |
Finish line：130mv |
|
Control area：200mv |
Control area：25ug/min |
|
Mixing time：30s |
Termination type: Cessation of relative drift |
|
The rate of liquid addition at the beginning: relatively slow |
Final volume: 10mL |
|
Maximum refilling rate：5mL/min |
Minimum liquid addition rate：80uL/min |
Iv. Results and Discussion
4.1 Experimental Results
The experimental results are as shown in Table 2:
Table 2 Test Results
|
Sample Number |
Titrant Concentration (mg/mL) |
Sample Volume (g) |
Titrant Volume (mL) |
Moisture Content (%) |
|
1 |
5.0 |
2.239 |
0.198 |
0.042 |
|
2 |
2.536 |
0.221 |
0.042 |
|
|
3 |
2.391 |
0.205 |
0.041 |
4.2. Conclusions and Precautions
The JH-V5 Karl Fischer moisture titrator measures the moisture content of soybean oil. The data repeatability is good. The instrument can automatically control the titration process, determine the endpoint and calculate the results, reducing errors caused by human factors. It has the characteristics of being fast and simple. It should be noted that:
The setting of the stirring time should be based on the dissolution state of the sample. If the dissolution is slow, the stirring time should be appropriately extended.
2) The solubility of the sample in the solvent is limited. According to the visual observation, if it is found that the sample cannot dissolve in the solvent, please replace it with a new solvent in time to avoid affecting the test results.
References
[1]GB 5009.3 National Food Safety Standard - Determination of Moisture in Food (Karl Fischer Method) [S]
Keyword:
Determination of moisture content in soybean oil by volumetric method,volumetric method
WELCOME TO JIAHANG
Do you want to Send Inquiry ?
COMPANY CONTACTS
Office Tel: +86-177-2114-8861
+86150-0214-1603
E-mail:gm@jiahanglab.com
sales03@jiahanglab.com
Add: Building B, No.3570 Jiasong North Road, Jiading District , Shanghai
Mob/Whatspp: 0086 177 2114 8861
Copy Right © 2023 Shanghai Jiahang Instruments Co., Ltd. All Rights Reserved
0086 17721148861
+86-17721148861
E-mail 
