GB/T 18798.3-2008Instant tea in solid form -- Part 3: Determination of moisture content (English PDF)

Foreword

GB/T 18798 "solid instant tea" is divided into the following sections.

--- Part 1. Sampling;

--- Part 2. Determination of total ash;

--- Part 3. Determination of moisture content;

This section GB/T 18798 Part 3, ISO 7513 corresponds to 1990 "Moisture solid instant tea." the partial modification of the use of ISO 7513:1990.

This part of ISO 7513 in the main technical content. the same as 1990, in the preparation of rules GB/T 1.1-2000 "Standardization according to Working Guidelines Part 1. Standard structure and drafting of rules "were developed.

This section important technical indicators and ISO 7513:1990 same, but in the specific preparation of the content, format and ISO 7513:1990 in the presence of Column Differences.

--- Delete ISO 7513:1990 Chapter 3, "principle" of the two "Note";

--- Delete ISO 7513:1990 Chapter 5, "sampling" in the "note", the note of the contents included in the sample;

--- Increase the "definition" of Chapter 3;

--- Combined ISO 7513:1990 Chapter 7 "sample weighing 7.2" and "following the determination" for the measuring step, and delete "7.4 Determination frequency";

--- For ease of calculation, the ISO 7513:1990 Chapter 8, "formula" in the m1 and m1 2 plus Lvhe quality;

--- Delete ISO 7513:1990 in 9.1 "repetitive" in the moisture limit of 3% to 4%, this index and China's production of solid-state speed Soluble tea sub-match;

--- Delete ISO 7513:1990 in 9.2;

--- Delete ISO 7513:1990 Chapter 10, "test report";

--- The ISO 7513:1990 Chapter 7, "Sample Preparation" later chapters on the analysis of the operation, unified included in Chapter 6, "Operation Party Law "within.

This Part replaces GB/T 18798.3-2002 "Moisture solid instant tea." this part is proposed by the China Federation of Supply and Marketing Cooperatives.

This part of the National Standardization Technical Committee under the jurisdiction of tea.

1 Scope

This section GB/T 18798 specifies the principles of moisture determination in solid instant tea, apparatus and appliances, and the result of the calculation method of operation method.

This section applies to the determination of moisture solid instant tea.

2 Normative references

The following documents contain provisions which, through reference GB/T 18798 in this section constitute provisions of this section. For dated reference documents Member, all subsequent amendments (not including errata content) or revisions do not apply to this section, however, encouraged to reach under this section Parties to research agreement to use the latest versions of these documents. For undated reference documents, the latest versions apply to this section.

GB/T 18798.1 solid instant tea - Part 1. Sampling (GB/T 18798.1-2008, ISO 7516. 1984, IDT)

3 Terms and Definitions

The following terms and definitions apply GB/T 18798 in this section.

Sample at a temperature of 103 °C, the mass loss was heated for 2h.

Principle 4

The sample is heated to remove moisture 2h at 103 °C ± 2 °C constant temperature oven, weighed.

5 Apparatus and appliances

Conventional laboratory equipment and the following.

5.1 blast oven temperature. it can automatically control the temperature of 103 °C ± 2 °C.

5.2 aluminum baking pan. with cover, diameter 75mm ~ 80mm.

5.3 dryer. containing more effective desiccant.

5.4 Analysis of balance. a sense of the amount of 0.001g.

6 Operation