SN/T 4675.22-2016Determination of total sulfur dioxide in wine for export--Colorimetric method (English PDF)

Foreword

SN/T 4675 "Export Wine Quality Analysis Method" is divided into 30 parts.

---SN/T 4675.1 Determination of glycerol in exported wines;

---SN/T 4675.2 Determination of 2,3-butanediol in exported wines by gas chromatography;

---SN/T 4675.3 Determination of the stable carbon isotope ratio of ethanol in exported wines;

---SN/T 4675.4 Determination of lactic acid in exported wines;

--- SN/T 4675.5 Determination of organic acids in exported wines by ion chromatography;

---SN/T 4675.6 Determination of glucose, fructose and sucrose in exported wines;

--- SN/T 4675.7 Determination of acetaldehyde in exported wines by gas chromatography-mass spectrometry;

--- SN/T 4675.8 Determination of 5-hydroxymethylfurfural in exported wines by liquid chromatography;

--- SN/T 4675.9 Determination of diethylene glycol in exported wines by gas chromatography-mass spectrometry;

---SN/T 4675.10 Determination of ochratoxin A in exported wines by liquid chromatography-mass spectrometry/mass spectrometry;

---SN/T 4675.11 Determination of seven anthocyanins in exported wines by ultra performance liquid chromatography;

---SN/T 4675.12 Determination of lysozyme in exported wines by liquid chromatography;

--- SN/T 4675.13 Determination of 2,4,6-trichloroanisole residues in exported wines by gas chromatography-mass spectrometry;

---SN/T 4675.14 Determination of natamycin in exported wines by liquid chromatography-mass spectrometry/mass spectrometry;

---SN/T 4675.15 Determination of salicylic acid, dehydroacetic acid and p-chlorobenzoic acid in exported wines by liquid chromatography;

---SN/T 4675.16 Determination of fumaric acid in exported wines by liquid chromatography-mass spectrometry/mass spectrometry;

--- SN/T 4675.17 Determination of butyl tin content in exported wines by gas chromatography - mass spectrometry/mass spectrometry;

--- SN/T 4675.18 Determination of residual dithiocarbamate in exported wines.

---SN/T 4675.19 Determination of sodium, magnesium, potassium, calcium, chromium, manganese, iron, copper, zinc, arsenic, selenium, silver, cadmium and lead in exported wines;

---SN/T 4675.20 Determination of rare earth elements in exported wines by inductively coupled plasma mass spectrometry;

--- SN/T 4675.21 Determination of soluble inorganic salts in exported wines by ion chromatography;

---SN/T 4675.22 Determination of total sulfur dioxide in exported wines;

---SN/T 4675.23 Determination of ammonia nitrogen in exported wines and grape juices - Continuous flow analyzer method;

---SN/T 4675.24 Determination of the export wine Fulin-Shoka index spectrophotometer method;

--- SN/T 4675.25 Determination of the color of exported wine CIE1976 (L * a * b *) color space method;

---SN/T 4675.26 Determination of turbidity of exported wines by scattered light method;

---SN/T 4675.27 Determination of alkaline ash in exported wines;

---SN/T 4675.28 Counting bacteria, mold and yeast for exporting wine;

---SN/T 4675.29 Real-time fluorescent PCR method for wine yeast test in exported wine;

---SN/T 4675.30 In the wine, the Bayesian yeast test real-time fluorescent PCR method.

This part is the 22nd part of SN/T 4675.

This part is drafted in accordance with the rules given in GB/T 1.1-2009.

This part is proposed and managed by the National Certification and Accreditation Administration.

This section drafted by. Shanghai Entry-Exit Inspection and Quarantine Bureau of the People's Republic of China, Guangdong Province Entry and Exit Inspection Epidemic situation.

1 Scope

This part of SN/T 4675 specifies the colorimetric method for the determination of total sulfur dioxide in wine.

This section applies to the determination of total sulfur dioxide content in wine.

2 Normative references

The following documents are indispensable for the application of this document. For dated references, only dated versions apply to this article.

Pieces. For undated references, the latest edition (including all amendments) applies to this document.

GB/T 6682 Analytical laboratory water specifications and test methods.

3 Method summary

After the sulfur dioxide in the sample is absorbed by the formaldehyde buffer solution, a stable methylolsulfonic acid addition compound is formed, and hydrogen is added to the sample solution.

Sodium oxide decomposes the addition compound, and the released sulfur dioxide reacts with pararosaniline and formaldehyde to form a purple-red compound at the wavelength.

The absorbance at 577 nm is proportional to the sulfur dioxide content. Quantification by external standard method.

4 Reagents and materials

Unless otherwise stated, the reagents used were of analytical grade and the water was secondary water as specified in GB/T 6682.

4.1 Sodium hydroxide.

4.2 trans-1,2-cyclohexylenedinitrilotetraacetic acid, referred to as CDTA.

4.3 Ethylenediaminetetraacetic acid disodium salt (C10H14N2O8Na2·2H2O).

4.4 Sulfamic acid.

4.5 Formaldehyde solution. 36%~38%.

4.6 Potassium hydrogen phthalate.

4.7 Pararosaniline hydrochloride (referred to as PRA, ie, by-product magenta or to magenta).

4.8 Phosphoric acid. 85%.

4.9 Hydrochloric acid. 36%~38%.

4.10 Sulfur dioxide standard. sodium sulfite (Na2SO3) (analytical grade, >=98%, CAS number. 7757-83-7), should be used after calibration concentration.

Or use a certified standard solution directly.

4.11 Sodium hydroxide solution (1.5 mol/L). 6.0 g of sodium hydroxide was weighed and dissolved in 100 mL of water.

4.12 Disodium hexamethylenediaminetetraacetic acid solution (0.05mol/L). Weigh 1.82g of trans 1,2-cyclohexanediaminetetraacetic acid and add sodium hydroxide Liquid (4.11) 6.5 mL, diluted to 100 mL with water.

4.13 Ethylenediaminetetraacetic acid disodium salt (EDTA-2Na) solution (0.50g/L). weigh 0.25g of ethylenediaminetetraacetic acid disodium salt, soluble 500 mL of freshly boiled and cooled water. Available at the time of use.

4.14 Sodium sulfamate solution [c(NaH2NSO3)=6.0g/L]. Weigh 0.36g sodium hydroxide, put it in a 100mL beaker, dissolve in water