1 Scope
This standard specifies two determination methods for peroxide value in foods: titration and potentiometric titration.
Method I in this standard is applicable to edible animal and vegetable fats and oils, edible fat and oil products, foods made of wheat flour, cereal, nuts and other vegetable food through processing techniques such as frying, puffing, baking, brewing and sauting, as well as those made of animal food through the processing techniques such as quick freezing, dry processing and salting away; Method II is applicable to animal and vegetable fats and oils and margarine with the measurement range of 0 g/100g ~ 0.38 g/100g.
This standard is not applicable to determination of embedded fat and oil products like vegetable fat powder.
Method 1 Titration
2 Theory
The oil and fat specimen prepared will be dissolved in trichloromethane and glacial acetic acid, during which the peroxide will react with potassium iodide to produce iodine that will be titrated by sodium thiosulfate standard solution. The amount of peroxide value shall be expressed by the mass fraction of the peroxide equivalent to iodine or the mill mole quantity of the active oxygen in 1 kg of the sample.
3 Reagents and Materials
Unless otherwise specified, analytically-pure reagents and Class III water (defined in GB/T 6682) are adopted for the purpose of this method.
Foreword i
1 Scope
2 Theory
3 Reagents and Materials
4 Instruments and Apparatuses
5 Analysis Steps
6 Expression of Analysis Results
7 Accuracy
8 Theory
9 Reagents and Materials
10 Instruments and Apparatuses
11 Analysis Steps
12 Expression of Analysis Results
13 Accuracy
