YC/T 159-2002 English PDF (YCT159-2002)

This Standard specifies the determination method for water soluble sugar in tobacco. This Standard applies to tobacco and tobacco products.

YC/T 159-2002
TOBACCO INDUSTRY STANDARD OF
THE PEOPLE’S REPUBLIC OF CHINA
ICS 65.160
X 87
File No.: 10589-2002
Tobacco and tobacco products - Determination
of water soluble sugars - Continuous flow method
[Replaced by YC/T 159-2019, from Feb 2020]
ISSUED ON: SEPTEMBER 12, 2002
IMPLEMENTED ON: DECEMBER 01, 2002
Issued by: State Tobacco Monopoly Administration
Table of Contents
Foreword ... 3
1 Scope ... 4
2 Normative references ... 4
3 Principle ... 4
4 Reagents ... 4
5 Instruments ... 6
6 Analysis steps ... 7
7 Calculation and expression of results ... 8
8 Precision ... 9
Tobacco and tobacco products - Determination
of water soluble sugars - Continuous flow method
1 Scope
This Standard specifies the determination method for water soluble sugar in tobacco.
This Standard applies to tobacco and tobacco products.
2 Normative references
The following documents contain the provisions which, through reference in this Standard, become the provisions of this Standard. For dated references, their subsequent amendments (excluding corrigendum) or revisions do not apply to this Standard. However, the parties who enter into agreement based on this Standard are encouraged to investigate whether the latest versions of these documents are applicable. For undated reference documents, the latest
versions apply to this Standard.
GB/T 5606.1 Cigarettes - Sampling
YC/T 5 General principles of batch sampling of tobacco leaves
YC/T 31 Tobacco and tobacco products - Preparation of test sample and
determination of water content - Oven method
3 Principle
Use 5 % aqueous acetic acid solution to extract tobacco samples. The sugar (it shall be hydrolyzed when determining water soluble total sugar) in the extract reacts with p-hydroxybenzoic acid hydrazide to produce a yellow azo in an alkaline medium at 85°C. The compound, whose maximum absorption
wavelength is 410 nm, is measured with a colorimeter.
NOTE: If it is extracted with water, the sucrose in some samples will be hydrolyzed. 4 Reagents
When using analytical reagents, the water shall be distilled water or water of equivalent purity.
4.1 Brij35 solution (polyethoxy lauryl ether)
ADD 250 g of Brij35 to 1 L of water, HEAT and STIR until dissolved.
4.2 0.5 mol/L sodium hydroxide solution
ADD 20 g of flake-shaped sodium hydroxide to 800 mL of water, STIR and leave to COOL. After dissolution, ADD 0.5 mL of Brij 35 (4.1), and DILUTE to 1 L with water.
4.3 0.008 mol/L calcium chloride solution
DISSOLVE 1.75 g of calcium chloride (CaCl2 • 6H2O) in water, ADD 0.5 mL of Brij 35 solution (4.1), and DILUTE to 1 L with water.
NOTE: If there is precipitation in the solution, filter it with qualitative filter paper. 4.4 5 % acetic acid solution
USE glacial acetic acid to prepare 5 % acetic acid solution (this solution is used to prepare standard solution and extraction solution).
4.5 Activate 5 % acetic acid solution
TAKE 1 L of 5 % acetic acid solution (4.4), and ADD 0.5 mL of Brij 35 solution (4.1) (this solution is used to flush the system).
4.6 0.5 mol/L hydrochloric acid solution
In a fume hood, slowly ADD 42 mL of fuming hydrochloric acid (mass fraction of 37 %) to 500 mL of water, and DILUTE to 1 L with water.
4.7 1.0 mol/L hydrochloric acid solution
In a fume hood, slowly ADD 84 mL of fuming hydrochloric acid (mass fraction of 37 %) to 500 mL of water, ADD 0.5 mL of Brij 35 solution (4.1), and DILUTE to 1 L with water.
4.8 1.0 mol/L sodium hydroxide solution
DISSOLVE 40 g of flake sodium hydroxide with 500 mL of water, and DILUTE to 1 L with water.
4.9 5 % p-hydroxybenzoic acid hydrazide solution (HOC6H4CONHNH2)
ADD 250 mL of 0.5 mol/L hydrochloric acid solution (4.6) to a 500 mL volumetric flask, ADD 25 g of paraben hydrazide to dissolve it. ADD 10.5 g of citric acid 5.1 Continuous flow analyzer (see Figure 1), consisting of the following parts: - sampler;
- proportional pump;
- dialyzer;
- heating tank;
- spiral tube;
- colorimeter, with 410 nm optical filter;
- recorder.
5.2 Balance, with a sensitivity of 0.0001 g.
5.3 Oscillator.
6 Analysis steps
6.1 Sampling
Take samples according to GB/T 5606.1 or YC/T 5.
6.2 Prepare samples according to YC/T 31, and determine the moisture content. 6.3 WEIGH 0.25 g of the sample in a 50 mL milled triangular flask, to the nearest 0.0001 g; ADD 25 mL of 5 % acetic acid solution; COVER with a stopper;
SHAKE and EXTRACT on an oscillator for 30 min.
6.4 FILTER with qualitative filter paper, DISCARD the first few milliliters of filtrate and COLLECT subsequent filtrate for analysis.
6.5 Operate the apparatus with working standard solution and sample solution. If the concentration of the sample solution exceeds the concentration range of the working standard solution, it shall be diluted.