Soaps test in Oils and Fats

CDR FoodLab, the fats and oils chemical analysis system for quality and process controlseither in a laboratory or on the production line Soaps are salts of fatty acids obtained from a reaction that occurs between free fatty acids and sodium carbonate. Thanks to their water solubility and insolubility in oil, they can be separated from fat through specific procedures. Food industries use this technique to lower fat acidity and to enhance its organoleptic characteristics. For such industries, it is important to carry out a chemical analysis for determining the concentration of soaps in oil and fat.

CDR FoodLab® method simplifies and speeds up the official procedure C8 NGD-1976 for testing the soaps in fats and, thanks to micro quantities used, allows to extend the analysis to samples of fat extraction is difficult.

Systems to test Soap in animal and vegetable fats and oils

 CDR FoodLab analyzer for oils and fats testing CDR FOODLAB®
Food MatricesAnimal and vegetable fats and oils
ParametersFFA (Acidity)
Peroxide Value (PV)
p-Anisidine Value (AnV)


Test type: End Point.
Testing time: immediate.
It is possible to carry out several test sessions with a maximum of 16 samples.

Test principle

At specific pH values soaps mixed with bromphenol, generate a specific blue colour. Its intensity, measured at 604 nm, is directly proportional to the concentration of soaps in the sample. CDR innovative method simplifies and accelerates the standard procedure to testing soaps in oils and fats, because it enables the test to be carried with micro-quantities and to be applied to fats that are difficult to extract.

Calibration Curve / Correlation Data

The method CDR FoodLab® for analyze the concentration of soaps in oils and fats shows a good correlation with the reference method NGD C8-1976

CDR FoodLab soaps analysis in oils and fats correlation with reference method



Reagent test Kits


The reagents are packaged in foil pouches containing 10 tubes useful to perform 10 analyses.

This is the minimum package that allows the use of CDR systems even to those who need to make a few analyses, thus not wasting reagents.

There are also boxes of 100 tests, however, packaged in 10 bags of 10 tubes containing the reagent.

Code. 300183 : 20 tests 

Code. 300175 : 100 tests (5 packages of 20 tests)

The reagents have a shelf-life of 12 months.

Sample Handling and Usage of Curves

Oil as is (extracted from dry fruits, seeds, nuts, etc.). Solid fats: melted using bain-marie method before starting the test (animal fats, palm oil, etc.).

Extractable fats: extract the fatty part following the instructions provided in the test method (butter, cream, margarine, semi-finished products, etc.).

AnalysisMeas. range
Sample VolumeResolution
Soaps1 – 300050 µL15 ppm

Reagent developed by CDR S.r.l - ISO 9001 certified company

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olive oil testing in few minutes
easy to use, compliance with AOCS methods

Soaps Test was last modified: May 23rd, 2017 by CDR s.r.l.