GB/T 6435-2014Determination of moisture in feedstuffs (English PDF)

Foreword

This standard was drafted in accordance with the rules given in GB/T

1.1-2009.

This standard replaces GB/T 6435-2006 "Determination of moisture and other

volatile matter content in feeds".

As compared with GB/T 6435-2006, the main changes are as follows.

- CHANGE the standard name to "Determination of moisture in feedstuffs";

- CHANGE from "Equivalent" into "Adopt through modification";

- MODIFY the paragraph 1 and 2 of the "Scope";

- In the "Scope", MODIFY the "cereals, excluding corn and cereal products"

into "cereals (excluding corn) and cereal products";

- In the "Scope", USE GB/T 9696 to replace ISO 662, and USE GB/T 21305

to replace ISO 712;

- DELETE the definition of "Moisture and other volatile matter"; ADD the

definition of "Moisture";

- ADD the specification requirements of the weighing bottle;

- MODIFY clause 8.1 ~ 8.4 to two clauses "Direct drying method" and

"Depressurized drying method";

- ADD the repeatability requirements for the samples of moisture content >=

15% through the direct drying method;

- DELETE clause 9.2 "Pretreated samples";

- DELETE Chapter 1, the note number of references in the appendix, AND

the reference ISO 5725-1.1994 in the appendix; RE-ARRANGE the order

of references.

This standard, through the redrafting method, modifies and adopts ISO

1 Scope

This standard specifies the determination method of moisture in feed,

feedstuffs and feed additives.

2 Normative references

The following documents are essential to the application of this document. For

the dated documents, only the versions with the dates indicated are applicable

to this document; for the undated documents, only the latest version (including

all the amendments) are applicable to this Standard.

3 Terms and definitions

The following terms and definitions apply to this document.

It refers to the mass of the substance loss (moisture and other volatile

matter) when drying the sample in accordance with the procedures as

specified in accordance with this standard.

4 Principles

Based on the sample nature, SELECT the specific conditions to dry the sample,

and CALCULATE the moisture through the mass loss during sample drying.

5 Instruments and materials

The instruments and materials commonly used in laboratory AND the following

instruments and materials.

6 Sampling

TAKE sample in accordance with GB/T 14699.1 or the methods as specified in

the relevant standards.

7 Sample preparation

PREPARE samples in accordance with GB/T 20195.

8 Analytical procedures

DRY the weighing bottle in accordance with clause 8.1 (solid sample using

5.2.1; semi-solid, liquid or fat-rich sample using 5.2.2); WEIGH its mass (m1),

accurate to 1 mg.

9 Calculation and representation of determination results

USE the arithmetic mean of two parallel determinations as the result, accurate

to 0.1%.

10 Precision

In the same laboratory, ARRANGE one operator to use the same equipment,

in accordance with the same determination method within a short time, to

conduct independent determination against the same sample under test, in

order to obtain the absolute difference of the two determination results, AND

those exceeding the repeatability r as given in Table 1 shall not be more than

5%.

11 Inspection report

The inspection report shall contain the following information.

Appendix A

(Informative)

Structural changes of this standard as compared with ISO 6496.1999

As compared with ISO 6496.1999, this standard has many structural changes,

AND the detailed clause number comparison is as shown in Table A.1.

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