Fruit and vegetable products — Determination of benzoic acid content (benzoic acid contents greater ...
The method consists in extracting the acid from an acidified test portion using diethyl ether, nitrating followed by reduction and Mohler's reaction modified with hydroxylaminehydrochloride, measuring the absorbance of the red complex obtained with a suitable spectrometer. For determining lower concentrations, see ISO 5518.
Green coffee — Determination of loss in mass at 105 degrees C
The method can be considered , by convention, as a method for determining the water content and can be used as such by agreement between interested parties. It consists in heating a test portion at 105 C for 16 h at atmospheric pressure.
Solvent acetates for industrial use — Methods of test
Gives general instructions and specifies methods of analysis for these chemical products. The methods are the following: determination of density at 20 °C; determination of dry residue after evaporation on a water bath; measurement of colour; determination of distillation characteristics; determination of water content; determination of acidity; and determination of ester content (titrimetric…
Iron ores — Determination of phosphorus content — Titrimetric method
This second edition cancels and replaces the first edition (i.e. ISO 2599:1973). Specifies a method using hexaammonium heptamolybdate (ammonium molybdate). The method is applicable to a concentration range of 0,10 to 5,0 % (m/m) of phosphorus in natural iron ores, and iron ore concentrates and agglomerates, including sinter products. Describes principle, reagents, apparatus, sampling and samples…
Brown coals and lignites — Principles of sampling — Part 1: Sampling for determination of moisture c...
Part 1 of this standard presents the principles of methods for the sampling of brown coals and lignites from streams, wagons, barges and stock-piles which differ from those described in sampling of hard coals. Other general principles and the procedure of replicate sampling are the same as for hard coals.
Animal and vegetable fats and oils — Determination of gallates content — Molecular absorption spectr...
Other antioxidants which can be detected and identified by the method specified in ISO 5558, may interfere and give high results. The principle of the method is selective extraction of each gallats from a test portion by means of appropriate solvents and determination by ultraviolet spectrometric measurement, in the following order: - propyl gallate, - octyl gallate, - dodecyl gallate.
Animal feeding stuffs — Determination of calcium content — Part 2: Atomic absorption spectrometric m...
The limit of detection is in the region of 10 mg/kg. The principle of the method is, following any necessary destruction of organic matter by incineration of a test portion, dissolution of the calcium by treatment with hydrochloric acid and dilution of the solution obtained, in the presence of lanthanum. Then determination of the calcium content by atomic absorption spectrometry.
Fruits, vegetables and derived products — Determination of cadmium content — Flameless atomic absorp...
The method consists in decomposing the organic matter as described in ISO 5515, and determining the dissolved cadmium cation with a suitable spectrometer.
