BS EN 14103 pdf free download

BS EN 14103 pdf free download.Fat and oil derivatives – Fatty Acid Methyl Esters (FAME) – Determination of ester and linolenic acid methyl ester contents.
5 Reagents
Use only reagents of recognized analytical grade, unless otherwise specified.
5,1 Toluene, analytical grade, no impurities of toluene eluting after methyl ester C6:0.
5.2 Nonadecanoic acid methyl ester (FAME C19:O), GC purity, mm. 99,0 % (rn/rn).
GC Purity of nonadecanoic acid methyl ester shall be checked for every new lot according to the procedure described in 8.2.
Standard shall be kept at room temperature in a dry storage (e.g. desiccator) in order to limit its water absorption. Its water content shall be below 0,2 % (rn/rn) and verified by Karl Fischer determination when a new lot of standard is opened.
If the purity is lower than 99,0 % (rn/rn) do not use it for this determination.
5.3 Carrier gas, hydrogen or helium, 99,999 5 % pure or better, gas chromatography quality, dried,
oxygen removed by suitable filters (<0,1 mg/kg), free from organic impurities.
5.4 Auxiliary gases, hydrogen and air, gas chromatography quality, free from organic impurities.
6 Apparatus
Usual laboratory apparatus and, in particular, the following.
6.1 Gas chromatograph, equipped with a variable split flow injector or equivalent device, a temperature programmable oven and a flame ionization detector.
6.2 Capillary column, coated with polyethylene glycol (Carbowax 20M) stationary phase, the following characteristics have been found suitable: length: 30 m, internal diameter: 0,25 mm, film thickness: 0,25 urn.
Stationary phase other than polyethylene glycol should be tested first before being selected as coelution between the internal standard (FAME C 19:0) and other fatty acid methyl esters may exist.
NOTE Indeed, there is a co-elution between FAME C19:0 and linoleic acid methyl ester (FAME C18:2) when using a column with a stationary phase such as 70 % cyanopropyl-polysilphenylene-siloxane (BPX7O).
6.3 Glass mono-use tubes, equipped with plastic mono-use stopper, 10 ml capacity.
6.4 Pipette, 10 ml capacity.
6.5 Analytical balance, accuracy ± 0,1 mg.
7 Sampling
Sampling is not part of the method specified in this European Standard. A recommended sampling method is given in EN ISO 5555 [1].
8 Procedure
8.1 Operating conditions
The chromatographic analysis conditions will be chosen taking into account the characteristics of the column being used and the type of carrier gas (hydrogen or helium).
By way of indication, an example of analysis conditions is described below:
• column temperature: 60 °C hold for 2 mm, programmed at 10 °C/min up to 200 C, programmed at 5 °C/min up to 240 °C, final temperature hold for 7 mm;
• injector temperature and detector temperature: 250 °C;
• carrier gas flow rate 1-2 mI/mm, a minimum flow rate of 1 ml/min shall be warranted when operating at the maximum temperature;
• injected volume: 1 p1;
• carrier gas (hydrogen) pressure: 70 kPa;
• split flow: 100 mI/mm.
8.2 Internal standard GC purity determination
In order to verify the absence of heavy impurities in the IS, the GC conditions were chosen according to
EN 14105.
Prepare a solution of nonadecanoic acid methyl ester in toluene approx. at 1 mg/ml. Analyse 1 p1 of this solution by gas chromatography on a capillary column of 15 m length and capable of being programmed up to 400 °C (“high temperature” type) with thin film thickness, with an on-column injector or equivalent device and flame ionization detection, according to the conditions described below. Analyse using the same conditions 1 p1 of toluene to verify that the impurities do not come from the solvent. Calculate the purity P of the rionadecanoic acid methyl ester taking into account all the peaks eluted in the chromatogram, excluding the solvent peak.
The purity of nonadecanoic acid methyl ester should be taken into consideration for the calculation of the ester content (see 9.1) and the linolenic acid methyl ester content (see 9.2)..
Byway of indication, an example of analysis conditions is described below:
• capillary column, capable of being programmed up to 400 °C (“high temperature” type) for which the following characteristics are advised: 100 % dimethylpolysiloxane or 95 % dimethyl – 5 % diphenyl-polysiloxane stationary phase; length 15 m; internal diameter 0,32 mm; film thickness 0,1 pm;
• column temperature: 50 °C hold for 1 mm, programmed at 15 °C/min up to 180 °C, programmed at 7 °C/min up to 230 °C, programmed at 10 °C/min up to 370 °C, final temperature hold for 15 mm;
• detector temperature: 380 °C;
• carrier gas pressure (hydrogen): 80 kPa;
• volume injected: 1 p1.BS EN 14103 pdf download.