COEI-2-CHROME Determination of chrome by atomic absorption spectrometry

1. Principle

The chrome is determined by atomic absorption spectrophotometer without flame.

COEI-2-CHLORU Search for chlorides

In a 160  16 mm test tube, place the volume prescribed of the solution obtained by the means indicated in each monography; add 5 ml of diluted nitric acid (R); complete to 20 ml and add 0.5 ml of silver nitrate solution at 5% (R).

COEI-2-CENDRE Sulphuric cinders

The sulphuric cinders result from the calcination after being in contact with air after being attacked by sulphuric acid.

COEI-2-CALCIU Determination of calcium by atomic absorption spectrometry

1. Principle

The calcium is directly determined in the liquid oenological product (or in the mineralisation solution) suitably diluted by atomic absorption spectrometry by air-acetylene flame after the addition of spectral buffer.

COEI-2-CADMIU Determination of cadmium by atomic absorption spectrometry

1. Principle

The cadmium is determined in solid oenological products after mineralisation by wet process or directly for liquid oenological products or put in a solution.

The determinations are performed by atomic absorption without a flame (electro-thermal atomisation in a graphite oven).

COEI-2-IBROME Bromine index

The bromine index is the quantity of bromine expressed in grammes, that 100 g of the substance can set.

1. Apparatus

A graduated flask of 300 to 400 ml with an interior tube welded at the bottom, an emery stopper and a tube with a handle, compliant with the following diagram

COEI-2-HYDCAR Aromatic polycyclic hydrocarbons

Determination of benzo(a)pyrene in oenological charbons by HPLC

1. Principle

Polycyclic aromatic hydrocarbons including benzoapyrene are extracted by hexane; the solvent is evaporated and the residue is taken up by the methanol-tetrahydrofuran for analysis by HPLC.

COEI-2-AZOTOT Determination of total nitrogen

1. Apparatus

1.1.    The apparatus used for separating NH₃ is either a distillation apparatus with a rectifying column or a distillation apparatus under a current of steam (diagram) made up of: