GB/T 14454.4-2008Fragrance/Flavor substances -- Determination of refractive index (English PDF)

Foreword

GB/T 14454, Fragrance/Flavor substances - General test methods, comprises the

following parts:

-- Part 1: Fragrance/Flavor substances - Preparation of test samples;

-- Part 2: Fragrance/Flavor substances - Method for valuation of odour;

-- Part 4: Fragrance/Flavor substances - Determination of refractive index;

-- Part 5: Fragrance/Flavor substances - Determination of optical rotation;

-- Part 6: Fragrance/Flavor substances - Quantitative evaluation of residue on

evaporation;

-- Part 7: Fragrance/Flavor substances - Determination of freezing point;

-- Part 11: Fragrance/Flavor substances - Determination of content of phenols;

-- Part 12: Fragrance/Flavor substances - Method for determination of trace

chlorinated compounds;

-- Part 13: Fragrance/Flavor substances - Determination of carbonyl value and

carbonyl compounds content;

-- Part 14: Fragrance/Flavor substances - Preparation of standard solution test

solution and indicator solution;

-- Part 15: Oil of sassafras - Determination of safrole and isosafrole content - Gas

chromatographic method on packed columns.

This Part is Part 4 of GB/T 14454.

This Part modifies and adopts ISO 280:1998, Fragrance/Flavor substances -

Determination of refractive index. Compared with ISO 280:1998, the major technical

differences of this Part are as follows:

-- the sampling method and repeatability of ISO 280:1998 are deleted;

-- Annex A is added.

This Part is a revision of GB/T 14454.4-1993, Fragrance/Flavor substances -

Determination of refractive index. Compared with GB/T 14454.4-1993, the major

changes of this Part are as follows:

-- the sampling method of GB/T 14454.4-1993 is deleted;

-- the conversion formula of refractive indexes at temperature t' and t is added;

Fragrance/Flavor substances –

Determination of refractive index

1 Scope

This Part of GB/T 14454 specifies the method for the determination of refractive index

of fragrance/flavor substances.

This Part applies to the determination of refractive index of fragrance/flavor substances.

2 Normative references

The provisions in following documents become the provisions of this Part through

reference in this Part. For dated references, the subsequent amendments (excluding

corrigendum) or revisions do not apply to this Part. However, parties who reach an

agreement based on this Part are encouraged to study if the latest versions of these

documents are applicable. For undated references, the latest edition of the referenced

document applies.

GB/T 14454.1, Fragrance/Flavor substances - Preparation of test samples (GB/T

14454.1-2008, ISO 356:1996, MOD)

3 Terms and definitions

For the purposes of this Part of GB/T 14454, the following terms and definitions apply.

3.1

refractive index

ratio of the sine of the angle of incidence to the sine of the angle of refraction, when a

ray of light of defined wavelength passes from air into the essential oil kept at a

constant temperature

NOTE: The wavelength specified is 589.3 nm ± 0.3 nm corresponding to the D1 and D2 lines of

the sodium spectrum.

4 Principle

According to the type of instrument used, either the angle of refraction is directly

measured or the limit of total reflection is observed, the oil being maintained under

conditions of isotropism and transparency.

5 Reagents

6 Apparatus

Commonly-used laboratory apparatus, especially the following apparatus:

7 Operating procedures