OIV-MA-F1-11 Specific methods for the analysis of grape sugar

Type IV method

ANNEX D.2: HEAVY METALS

Determination of lead content by Inductively Coupled Plasma Mass Spectrometry (ICP-MS).

The analysis of Pb in rectified concentrated grape musts can also be performed applying the method OIV/OENO 344/2010 (Multielemental Analysis Using ICP-MS), with the following modification added at the end of point N°5 (Sample preparation):

5.      Sample preparation

This method can also be applied to the analysis of Pb in rectified concentrated grape musts. For this purpose, a prior mineralisation of the sample is required. A digestion of the samples in a close vessel microwave system is recommended. The following procedure is given as a way of example:

Ad 1 g of must, 2 ml of nitric acid (3.4) and 8 ml of water (3.1) in a microwave vessel, and apply the following microwave digestion programme:

Once the samples have been digested, transfer them to a 50 ml plastic tube (4.6), dilute with water (3.1) to 30g and homogenize.