BS ISO 28198:2018,Vegetable fats and oils — Determination of toluene insoluble matter.BS ISO 28198:2018 pdf free download here.
BS ISO 28198:2018 specifies a method for the determination of the content of toluene insoluble matter (TIM) in lecithin formulations, which indicates the presence of impurities such as protein, carbohydrate-containing extraction residues and other solid contaminants. This method is applicable to all types of vegetable lecithin.
The purpose of the method is to enable the analysis of lecithin under several regulations. Lecithin [Codex International Numbering System for Food Additives (INS) No. 322] is a generally permitted additive and the determination of the TIM is part of many specifications. The purity requirement with regard to TIM content is based on the method specified.
Toluene is the replacement for the carcinogenic benzene, which was used in older methods.
10 Precision
10.1 Interlaboratory test
Details of interlaboratory tests on the precision of the method are summarized in Annex A. The values derived from these interlaboratory tests may not be applicable to concentration ranges and matrices other than those given.
10. 2 Repeatability
The absolute difference between two independent single test results, obtained with the same method on identical test material in the same laboratory by the same operator using the same equipment within a short interval of time, shall in not more than 5 of cases exceed the values of r given in Tables A,1 and A. 2.
10.3 Reproducibility
The absolute difference between two single test results, obtained with the same method on identical est material in different laboratories by different operators using different equipment, shall in not more than 5% of cases exceed the values of R given in Tables A. 1 and A.2.