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Analysis of mineral elements in wines using ICP-AES (inductively coupled plasma / atomic emission spectrometry) (Type-II)

OIV-MA-AS322-13 Analysis of mineral elements in wines using ICP-AES (inductively coupled plasma/atomic emission spectrometry)

Type III method

  1. Warning

 

Safety precautions - When handling acids, operators should protect their hands and eyes. Acids must be handled under a suitable hood.

  1. Scope

 

This method specifies an inductively coupled plasma atomic emission spectroscopy (ICP-AES) method to determine the concentration of the following elements in wines:

Major mineral elements:

  • Potassium (up to 1500 mg/L)
  • Calcium (up to 250 mg/L)
  • Magnesium (up to 150 mg/L)
  • Sodium (up to 100 mg/L)

Minor mineral elements:

  • Iron (1 to 10 mg/L)
  • Copper (0.1 to 5 mg/L)
  • Zinc (0.5 to 5 mg/L)
  • Manganese (0.5 to 5 mg/L)
  • Strontium  (0.1 to 3 mg/L)
  • Aluminium  (0.75 to 7.5 mg/L)
  • Barium (0.1 to 5 mg/L)
  1. Principle

3.1.  Simultaneous analysis of major and minor elements

A 1:5 dilution is used to prepare the samples in this method in order to be able to analyse both the major and minor elements.

The calibration range contains ethanol (2.5%) to take into account the matrix effects related to its presence during nebulisation and at the plasma temperature, along with nitric acid (HN - 1%) which is used to stabilise the solutions.

The lines (scandium at 5 mg/L) and (caesium as 1% in CsN) proposed in this method can be used as an internal standard in order to minimise the impact of other non-spectral interferences.

Other internal standards, chosen wisely, may also be used in order to optimise the method, such as .

Caesium, in the form of CsN. also serves as an ionic buffer when used as an internal standard. The presence of this buffer therefore sets the ionisation balances of the other components. Caesium chloride, CsCl, can also be used as an ionic buffer.

The internal standards and ionic buffer are prepared in the same flask and then introduced into the sample through the addition of a third channel in the peristaltic pump before entering the nebuliser as a homogenous mixture.

3.2.  Analysis of the major elements only

The analysis of the major elements only can also be performed by carrying out a 1:50 dilution of the sample. Nitric acid (HNO3 - 1%) is added into the standards and the samples in order to stabilise the solutions.

Given the dilution performed, the matrix effects are considered negligible. The use of internal standards will not be necessary. Likewise, there will be no need to add ethanol to the calibration range.

 

  1. Reagents and solutions

Unless otherwise specified, all the reagents used must be of a recognised analytical quality.

4.1.  Ultra-pure, demineralised water with a resistivity (greater than 18 MΩ), in accordance with the ISO 3696 standard.

4.2.  Certified mono-element solution(s) (to 1000 or 10,000 mg/L) for the mineral elements analysed and the internal standard (scandium for example).

4.3.  Internal control: certified reference material (wine) or sample from an intercomparison programme between laboratories, comprising the elements analysed.

4.4.  Nitric acid of a concentration greater than 60% (for trace analysis) (CAS No. 7697-37-2).

4.5.  Ethanol of a concentration greater than 95% (for trace analysis) (CAS No. 64-17-5).

4.6.  A solution of 1% nitric acid

Prepare a 1% nitric acid solution by adding 10 mL of nitric acid (4.4) into a 1000 mL flask.

  1. Apparatus and equipment

 

5.1.  Optical emission spectrometer with excitation by induced argon plasma and dispersive system (for wavelength analysis, see table in section 7) with axial, radial or dual configuration and preferably sequential PM, CCD, CID or SCCD type detector.

Note 1: Multi-element analysis using a simultaneous type spectrometer is strongly advised if an internal standard is used in the method.

Note 2: Other systems for introducing the sample may be used in order to increase the sensitivity and robustness of the method (continuous flow injection system, microwave desolvation system (MWDS, etc.).

5.2.  Calibrated micropipettes making it possible to take volumes from 200 µL to 5 mL and/or class A 1.5 and 10 mL graduated pipettes.

5.3.  Class A volumetric flasks

Note 3: The equipment in contact with the sample must remain in the nitric acid solution (4.4) at a concentration of 10% for 12 hours and then be rinsed several times with the demineralised water (4.1).

In order to assess the robustness of the method on the instrument used, it is recommended that the Mg 279.800/Mg 285.213 intensity ratio is calculated; Mg 285.213 being an atomic line and Mg 279.800 being an ionic line.

  1. Sample preparation

6.1.  Preparing the calibration range

The number of calibration solutions depends on the reliability required. At least five calibration solutions are needed. The reliability and accuracy of the results can be verified by analysing a reference material.

The range will be chosen according to the dilution performed. It should cover the scope of the various elements. It is important that the nitric acid concentration is the same in the standards and samples.

6.1.1.      Preparing a standard solution for simultaneous analysis of major and minor elements (1:5 dilution):

Using a micropipette (5.2), introduce the desired volume of standard, 2.5 mL of ethanol (4.5) and 1 mL of nitric acid (4.4) into a 100 mL flask (5.3). Make up to 100 mL with demineralised water (4.1) and mix.

6.1.2.      Preparing a standard solution for analysing major elements only (1:50 dilution):

Using a micropipette (5.2), introduce the desired volume of standard into a 100 mL flask (5.3), make up to 100 mL with nitric acid solution (4.6) and mix.

6.2.  Preparing the test samples

6.2.1.      Preparing test samples for simultaneous analysis of major and minor elements (1:5 dilution):

Using a graduated pipette or micropipette (5.2), introduce 10 mL of sample and 1 mL of nitric acid (4.4) into a 50 mL flask (5.3). Make up to 50 mL with demineralised water (4.1) and mix.

Sparkling wine samples must be subjected to degassing using an ultrasound bath for example, for at least 10 minutes.

Particularly for samples rich in sugar, mineralisation by microwave digestion in nitric acid is used to destroy organic compounds. Finally, a higher dilution may need to be considered due to a concentration which is too high for certain elements. In this case, the ethanol content may be adjusted accordingly in the solutions and standards.

Note 4: Depending on the robustness of the instrument used and given the use of the ionic buffer and internal standards, it is possible to work with a 1:2 dilution factor in order to improve the sensitivity of the method for trace elements. As a result, the calibration ranges, ethanol content and possibly the experimental parameters (power) must be modified.

6.2.2.      Preparing test samples for analysing major elements only (1:50 dilution)

Using a graduated pipette or micropipette (5.2), introduce 1 mL of wine sample and 0.5 mL of nitric acid (4.4) into a 50 mL flask (5.3). Make up to 100 mL with demineralised water (4.1) and mix.

  1. Procedure

Experimental parameters

 

The optimal instrument parameters that have enabled us to achieve the specificity for this method in terms of repeatability and reproducibility are described below. They are presented here as an example and may be modified depending on the instrument used.

Power: 1.3 kW

Plasma gas flow: 15 L/min

Auxiliary gas flow: 1.5 L/min

Nebuliser pressure: 200 kPa

Stabilisation period: 20 s

Measurement time per replicate: 5 s

Pump speed: 15 rpm

Rinsing time: 30 s

Internal standard inlet internal diameter: 0.51 mm

Sample inlet internal diameter: 0.8 mm

Turn the unit on (pump operational and plasma switched on) and clean the system for at least 20 minutes with 1% nitric acid (4.6).

Analyse a blank following the series of standards in increasing order of concentration. A reference sample (4.3) can be used as internal quality control to verify that the calibration is satisfactory. Next, analyse the blank again to ensure the absence of memory effect. Next, conduct the analysis of the samples by inserting a quality control every 10 samples and at the end of the analysis series.

A control chart can be drawn up from the results obtained in relation to the control sample in order to define the acceptance criteria and actions to be performed in the event of drift.

The analyses will be performed for each element with a minimum of 3 replicates.

Lines that can be used for the various elements (other lines may be used depending on the equipment).

 

Elements

Main line

()

Associated internal standard

Secondary line

()

Associated internal standard

K

769.897 (I) (1.6 eV)

Cs 697.327

766.491 (I) (1.6 eV)

Cs 697.327

Ca

317.933 (II) (10 eV)

Sc 335.372

315.887 (II) (10.1 eV)

Sc 335.372

Mg

285.213 (I) (4.3 eV)

Cs 697.327

279.800 (II) (10.6 eV)

Sc 335.372

Na

589.592 (I) (2.1 eV)

Cs 697.327

 

 

Fe

259.940 (II) (12.7 eV)

Sc 335.372

239.563 (II) (11.4 eV)

Sc 335.372

Cu

327.395 (I) (3.8 eV)

Cs 697.327

324.754 (I) (3.8 eV)

Cs 697.327

Zn

213.857 (I) (5.8 eV)

Cs 697.327

206.200 (II) (12.2 eV)

Sc 335.372

Mn

257.61 (II) (12.3 eV)

Sc 335.372

260.568 (II) (11 eV)

Sc 335.372

Sr

421.552 (II) (8.6 eV)

Sc 335.372

407.771 (II) (8.7 eV)

Sc 335.372

Al

396.152 (I) (3.1 eV)

Cs 697.327

167.019 (I) (7.4 eV)

Cs 697.327

Rb

780.026 (I) (1.6 eV)

Cs 697.327

 

 

Li

670.783 (I) (1.9 eV)

Cs 697.327

 

Ba

455.403 (II) (7.9 eV)

Sc 335.372

 

Sc

335.372 (II) (10.3 eV)

 

Cs

697.327 (I) (1.8 eV)

 

 

  1. Calculation

Calculate the concentration of the elements in the sample using the following equation:

Where:

C: concentration of the element in the wine sample (mg/L)

Cm: concentration of the element in the diluted solution (mg/L)

Vt: volume of the dilution flask (mL) (here V=50 mL)

Vm: volume of the sample taken for dilution (mL) (here V=1 or 10 mL)

  1. Precision

 

Elements

Repeatability
(RSD %)

Reproducibility
(RSD %)

LD (mg/L)

LQ (mg/L)

Recovery rate

K

2.3

5.5

major

major

Between 80% and 120%

Ca

3.5

11.3

major

major

Mg

2.4

8.9

major

major

Na

2.6

9.1

major

major

Fe

2.2

6.9

0.08

0.25

Cu

13.4

15.8

0.03

0.10

Zn

3.6

6.5

0.03

0.10

Mn

4.7

7.0

0.03

0.10

Al

5.6

17.0

0.03

0.10

Sr

2.1

9.9

0.03

0.10

Ba

8.2

20.8

0.03

0.10

 

Appendix :Validation study – Results of the collaborative trials

A validation study was performed in November 2011 (pre-study) and in February 2012 (validation study) in accordance with ISO 5725 and resolution OENO 6/2000.

Pre-study:

3 samples (dry white wine, red wine and sweet white wine), spiked with Al, Fe,

Cu, Sr, Ba, Mn and Zn.

 

Samples

Element (mg/L)

Red wine

Dry white wine

Sweet wine

K

1258

725

841

Ca

50

75

81

Na

20

28

24

Mg

78

70

66

Al

1.29

1.33

1.97

Fe

8.12

6.91

9.29

Cu

0.86

0.86

0.94

Sr

1.07

1.08

1.07

Ba

0.77

0.72

0.63

Mn

1.6

2.01

1.77

Zn

1.51

2.53

1.69

SAMPLES

White wine 1

White wine 2

Element

Ref value (mg/L)

Spike (mg/L)

Recovery %

Ref value (mg/L)

Spike (mg/L)

Recovery %

K

754

0

98

1080

351

96

Ca

83

11

98

76

0

102

Na

50

28

105

24

0

100

Mg

65

0

98

72

7

102

Al

0.50

0

100

1.19

1

104

Fe

2.86

1

94

1.71

0

97

Cu

0.04

0

no add.

0.71

1

103

Sr

1.27

1

105

0.22

0

108

Ba

0.08

0

102

0.64

1

96

Mn

1.84

1

98

1.12

0

102

Zn

1.40

0

100

2.12

1

102

 

 

Red wine 1

Red wine 2

Element

Ref value (mg/L)

Spike (mg/L)

Recovery %

Ref value (mg/L)

Spike (mg/L)

Recovery %

K

1160

70

100

1371

316

95

Ca

62

1

103

67

7

101

Na

71

56

100

19

0

100

Mg

82

7

102

80

0

99

Al

0.81

0

105

1.82

1

103

Fe

4.90

0

101

4.55

0

101

Cu

0.46

0

102

0.12

0

65

Sr

0.28

0

102

1.32

1

105

Ba

0.12

0

102

0.62

1

97

Mn

1.81

1

100

1.10

0

101

Zn

0.95

0

107

1.68

1

101

 

Sweet wine 1

Sweet wine 2

Element

Ref value (mg/L)

Spike (mg/L)

Recovery %

Ref value (mg/L)

Spike (mg/L)

Recovery %

K

1105

246

96

832

0

102

Ca

85

4

99

92

10

101

Na

68

42

98

21

0

100

Mg

63

0

97

66

6

101

Al

1.65

1

101

0.80

0

96

Fe

3.03

0

97

4.63

0

101

Cu

0.73

1

101

0.12

0

94

Sr

1.73

1

106

0.22

0

96

Ba

0.11

0

94

0.34

0

90

Mn

1.01

0

99

1.62

1

102

Zn

1.53

1

102

1.18

0

100

 

Participant laboratories had the choice to carry out the analysis of elements

  • either in two steps: high dilution for major elements and low dilution for minor elements, preferably with internal standards.
  • or in one step: the same dilution for all elements with internal standards.

For each sample number and for each determination, the first individual value was used. The two individual portions of blind identical replicas per laboratory are considered as a single material.

Outlier elimination was performed using a sequential application of the Cochran (applied to variances) and Grubbs (applied to mean values) tests (at a 2.5% probability (P) level, 1-tail for Cochran and 2-tail for Grubbs) until no further outliers were flagged or until a drop of 22.2% in the original number of laboratories providing valid data occurred.

With the exception of the element calcium in the "sweet wine 2" sample, which exhibits a Horrat R value of 2.2, all the elements were compliant. For this sample, 93% of the laboratories have a satisfactory Z-score (14 results) and 7% of the laboratories have a questionable Z-score (1 result). Consequently, as the five other samples were compliant for the determination of calcium, including another sweet wine sample with the same calcium concentration, it was decided to validate this element and to include it in the analytical method.

For the determination of major elements, 9 laboratories used a high dilution and 6 laboratories used a single dilution for all (major and minor) elements. There were no differences between the results of both groups.

Tableau 1 - Potassium

Statistical parametres

White

Wine 1

White

Wine   2

Red wine

1

Red wine

2

Sweet wine

1

Sweet wine

1

Total

15,00

15,00

15,00

15,00

15,00

15,00

Accepted

13,00

13,00

14,00

11,00

14,00

14,00

Repetitions

2,00

2,00

2,00

2,00

2,00

2,00

Vréf (mg/L)

754,38

1079,82

1160,33

1370,96

1105,46

831,62

Limit of repeatability - r

22,45

47,32

132,68

50,64

124,78

42,92

RSD r (%)

1,10

1,50

4,00

1,30

4,00

1,80

RSD r Horwitz

3,90

3,69

3,65

3,56

3,68

3,84

r Horrat

0,30

0,40

1,10

0,40

1,10

0,50

Limite de reproductibility - R

139,25

182,82

165,46

147,56

176,10

142,93

RSD R (%)

6,50

6,00

5,00

3,80

5,60

6,10

RSD R Horwitz

5,90

5,59

5,53

5,39

5,57

5,82

R Horrat

1,10

1,10

0,90

0,70

1,00

1,00

Tableau 2 - Calcium

Statistical parametres

White

Wine 1

White

Wine 2

Red wine

1

Red wine

2

Sweet wine

1

Sweet wine

1

Total

15,00

15,00

15,00

15,00

15,00

15,00

Accepted

10,00

10,00

13,00

10,00

13,00

15,00

Repetitions

2,00

2,00

2,00

2,00

2,00

2,00

Vréf (mg/L)

85,37

73,43

67,68

66,00

78,35

92,39

Limit of repeatability - r

3,30

4,12

4,60

2,86

7,96

  26,66

RSD r (%)

2,10

2,00

2,40

1,50

3,60

10,20

RSD r Horwitz

5,85

5,53

5,60

5,62

5,48

5,34

r Horrat

0,30

0,40

0,40

0,30

0,70

1,90

Limite de reproductibility - R

10,68

10,45

42,58

9,51

29,85

45,60

RSD R (%)

4,40

5,00

22,20

5,10

13,50

17,40

RSD R Horwitz

8,19

8,38

8,48

8,52

8,30

8,10

R Horrat

0,50

0,60

2,60

0,60

0,60

2,20

Tableau 3 - Sodium

Statistical parametres

White

Wine 1

White

Wine   2

Red wine

1

Red wine

2

Sweet wine

1

Sweet wine

1

Total

15,00

15,00

15,00

15,00

15,00

15,00

Accepted

15,00

13,00

12,00

12,00

14,00

15,00

Repetitions

2,00

2,00

2,00

2,00

2,00

2,00

Vréf (mg/L)

50,50

24,09

71,43

18,76

67,91

21,42

Limit of repeatability - r

3,00

1,32

2,53

1,73

5,20

1,85

RSD r (%)

2,10

1,90

1,20

3,30

2,70

3,00

RSD r Horwitz

5,85

6,54

5,55

6,79

5,60

6,6

r Horrat

0,30

0,30

0,20

0,50

0,50

0,50

Limite de reproductibility - R

9,41

6,09

15,19

6,72

13,09

6,49

RSD R (%)

6,60

9,90

7,50

12,70

6,80

10,70

RSD R Horwitz

8,87

9,91

8,42

10,29

8,48

10,09

R Horrat

0,70

0,90

0,90

1,20

0,80

1,10

Tableau 4 - Magnésium

Statistical parametres

White

Wine 1

White

Wine   2

Red wine

1

Red wine

2

Sweet wine

1

Sweet wine

1

Total

15,00

15,00

15,00

15,00

15,00

 15,00

Accepted

15,00

15,00

14,00

14,00

13,00

14,00

Repetitions

2,00

2,00

2,00

2,00

2,00

2,00

Vréf (mg/L)

65,30

72,0

82,15  

80,01  

62,63

65,53

Limit of repeatability - r

3,43

4,29

10,27  

7,25

5,32

2,27

RSD r (%)

1,90

2,10

4,40

3,20

3,00

1,20

RSD r Horwitz

5,63

5,55

5,44

5,46

5,67

5,63

r Horrat

0,30

0,40

0,80

0,60

0,50

0,20

Limite de reproductibility - R

15,26

16,33

29,80  

20,23

15,86

13,74

RSD R (%)

8,30

8,00

12,80  

8,90

8,90

7,40

RSD R Horwitz

8,53

8,40

8,24

8,2

8,58

8,53

R Horrat

1,00

1,00

1,60

1,10

1,00

0,90

Tableau 5 - Aluminium

Statistical parametres

White

Wine 1

White

Wine   2

Red wine

1

Red wine

2

Sweet wine

1

Sweet wine

1

Total

15,00

15,00

15,00

15,00

15,00

15,00

Accepted

10,00

9,00

8,00

8,00

9,00

8,00

Repetitions

2,00

2,00

2,00

2,00

2,00

2,00

Vréf (mg/L)

0,50

1,19

 0,81

1,82

1,65

0,80

Limit of repeatability - r

0,19

0,11

0,22

0,15

0,15

0,05

RSD r (%)

13,10

3,30

9,40

2,80

3,20

2,10

RSD r Horwitz

11,71

10,29

10,89

9,65

9,79

10,93

r Horrat

1,10

0,30

0,90

0,30

0,30

0,20

Limite de reproductibility - R

0,42

0,33

0,33

0,46

0,97

0,41

RSD R (%)

29,80

10,00

14,20

8,90

20,80

18,10

RSD R Horwitz

17,75

15,59

16,50

14,61

14,84

16,56

R Horrat

1,70

0,60

0,90

0,60

1,40

1,10

Tableau 6 - Fer

Statistical parametres

White

Wine 1

White

Wine   2

Red wine

1

Red wine

2

Sweet wine

1

Sweet wine

1

Total

 10,00

10,00

10,00

10,00

10,00

10,00

Accepted

6,00

7,00

7,00

6,00

7,00

7,00

Repetitions

2,00

2,00

2,00

2,00

2,00

2,00

Vréf (mg/L)

2,86

1,71

4,90

4,55

3,03

4,63

Limit of repeatability - r

0,19

0,06

0,57

0,33

0,21

0,70

Limit of repeatability - r

0,19

0,06

0,57

0,33

0,21

0,70

RSD r (%)

2,30

1,30

4,10

2,60

2,40

0,50

RSD r Horwitz

9,02

9,74

8,31

8,41

8,94

8,38

r Horrat

0,30

0,10

0,50

0,30

0,30

0,10

Limite de reproductibility - R

0,20

0,29

0,99

0,34

0,34

2,52

RSD R (%)

2,50

6,10

7,10

2,60

3,90

19,20

RSD R Horwitz

13,66

14,76  

12,59

12,74

13,54

12,70

R Horrat

0,20

0,40

0,60

0,20

0,30

1,50

Tableau 7 - Cuivre

Statistical parametres

White

Wine 1

White

Wine   2

Red wine

1

Red wine

2

Sweet wine

1

Sweet wine

1

Total

9,00

10,00

10,00

10,00

10,00

10,00

Accepted

7,00

10,00

8,00

10,00

8,00

10,00

Repetitions

2,00

2,00

2,00

2,00

2,00

2,00

Vréf (mg/L)

0,04

0,71

0,46

0,12

0,73

0,12

Limit of repeatability - r

  0,03

0,10

0,08

 0,05

0,03

0,10

RSD r (%)

24,30

4,80

6,00

14,40

1,70

29,00

RSD r Horwitz

16,95

11,12

11,87

14,62

11,07

14,55

r Horrat

1,40

0,40

0,50

1,00

0,20

2,00

Limite de reproductibility - R

0,03

0,21

0,09

0,05

0,14

0,10

RSD R (%)

24,30

10,40

6,80

16,40

6,80

30,10

RSD R Horwitz

25,68

16,84

17,98

22,15

16,77

22,05

R Horrat

0,90

0,60

0,40

0,70

0,40

1,40

Tableau 8 – Strontium

Statistical parametres

White

Wine 1

White

Wine   2

Red wine

1

Red wine

2

Sweet wine

1

Sweet wine

1

Total

8,00

8,00

8,00

8,00

8,00

 8,00

Accepted

7,00

7,00

7,00

6,00

7,00

6,00

Repetitions

2,00

2,00

2,00

2,00

2,00

2,00

Vréf (mg/L)

1,27

0,22

0,28

1,32

1,73

0,22

Limit of repeatability - r

0,03

 0,01

0,04

0,06

0,12

 0,00

RSD r (%)

1,00

1,70

5,50

1,70

2,60

0,50

RSD r Horwitz

10,19

13,25

12,76

10,13

9,72

13,30

r Horrat

0,01

0,10

0,40

0,20

0,30

0,00

Limite de reproductibility - R

0,18

0,07

0,12

0,09

0,24

0,12

RSD R (%)

5,10

11,40

15,30

2,50

5,00

20,00

RSD R Horwitz

15,44

20,08

19,34

15,34

14,73

22,15

R Horrat

0,30

0,60

0,80

0,20

0,30

1,00

Tableau 9 - Barium

Statistical parametres

White

Wine 1

White

Wine   2

Red wine

1

Red wine

2

Sweet wine

1

Sweet wine

1

Total

8,00

8,00

8,00

8,00

8,00

8,00

Accepted

7,00

 8,00

8,00

7,00

8,00

8,00

Repetitions

2,00

2,00

2,00

2,00

2,00

2,00

Vréf (mg/L)

0,08

0,64

0,12

0,62

0,11

0,34

Limit of repeatability - r

0,01

0,38

0,01

0,16

0,01

0,06

RSD r (%)

5,70

21,00

3,60

9,20

3,30

6,30

RSD r Horwitz

15,33

11,30

14,52

11,34

14,73

12,41

r Horrat

0,40

1,90

0,20

0,80

0,20

0,50

Limite de reproductibility - R

0,04

0,38

0,05

0,54

0,05

0,24

RSD R (%)

18,80

21,00  

13,90

30,07

15,80

24,50

RSD R Horwitz

23,23

17,12

22,00

17,18

22,32

18,80

R Horrat

0,80

1,20

0,60

1,80

0,70

1,30

Tableau 10 - Manganèse

Statistical parametres

White

Wine 1

White

Wine   2

Red wine

1

Red wine

2

Sweet wine

1

Sweet wine

1

Total

10,00

10,00

10,00

10,00

 10,00

10,00

Accepted

9,00

10,00

9,00

10,00

8,00

8,00

Repetitions

2,00

2,00

2,00

2,00

2,00

2,00

Vréf (mg/L)

1,84

1,12

1,81

1,10

0,11

1,62

Limit of repeatability - r

0,09

  0,21

0,49

0,14

0,13

0,60

RSD r (%)

1,60

6,50

9,60

4,50

4,60

1,30

RSD r Horwitz

9,64

10,38

9,66

10,41

 10,55

9,82

r Horrat

0,20

0,60

1,00

0,40

0,40

0,10

Limite de reproductibility - R

0,25

0,21

0,49

0,22

0,22

0,38

RSD R (%)

4,80

6,50

9,60

7,10

7,10

8,30

RSD R Horwitz

14,60

15,73

14,63

15,78

15,98

14,88

R Horrat

0,30

0,40

0,70

0,50

0,30

0,60

Tableau 11 - Zinc

Statistical parametres

White

Wine 1

White

Wine   2

Red wine

1

Red wine

2

Sweet wine

1

Sweet wine

1

Total

10,00

10,00

10,00

10,00

10,00

10,00

Accepted

7,00

8,00

9,00

8,00

7,00

7,00

Repetitions

2,00

2,00

2,00

2,00

2,00

2,00

Vréf (mg/L)

1,40

2,12

0,95

1,68

1,53

1,18

Limit of repeatability - r

  0,09

0,16

0,22

0,10

0,18

0,05

RSD r (%)

2,40

2,60

8,40

2,20

4,20

1,60

RSD r Horwitz

10,03

9,43

10,65

9,77

9,91

10,30

r Horrat

0,20

0,30

0,80

0,20

0,40

0,20

Limite de reproductibility - R

0,10

0,39

0,29

0,36

0,22

0,22

RSD R (%)

2,40

6,50

10,70

7,60

5,10

6,70

RSD R Horwitz

15,20

14,28

16,13

14,80

15,01

15,61

R Horrat

0,20

0,50

0,70

0,50

0,30

0,40

2/ Laboratoires participants :

  • State General Laboratory, NMR Lab, Nicosia Chypre
  • ANALAB CHILE S.A., Santiago Chile
  • CISTA, National Reference Laboratoty Brno Czech Republic
  • Laboratório de Análises- REQUIMTE- FCT/UNL, Caparica Portugal
  • Laboratório Central de Análises - Universidade de Aveiro Portugal
  • Laboratory of National Center of Alcoholic Beverages Testing, Chisinau Republic of Moldova
  • National Research Institute of Brewing, Higashihiroshima Japon
  • Instituto Nacional de Vitivinicultura, Laboratorio General, Mendoza Argentine
  • LFZ Wein und Obstbau, Klosterneuburg Autriche
  • Laboratorio Arbitral Agroalimentario, Madrid Spain
  • Laboratoire SCL de Bordeaux-Pessac France