LS/T 6118-2017Inspection of grain and oils - Determination and evaluation of fresh degree of paddy (English PDF)

Foreword

This standard was drafted in accordance with the rules given in GB/T 1.1-2009.

This standard was proposed by the National Grain Administration.

This standard is under the jurisdiction of the National Grain and Oil Standardization Technical Committee (SAC/TC270).

This standard is mainly drafted by. National Quality Bureau Standard Quality Center, Beijing Dongfang Fude Technology Development Center, Liaoning Provincial Grain and Oil Inspection Supervision Institute of Testing, Anhui Provincial Grain and Oil Product Quality Testing Station, Jiangxi Provincial Grain and Oil Quality Supervision and Inspection Center, Jiangsu National Grain Quality Monitoring Center, Guangdong Product quality supervision and inspection station, Changzhou Grain and Oil Quality Supervision and Inspection Station.

1 Scope

This standard specifies the terms and definitions, principles, reagents, instruments, samples, determination methods, results, and fresh rice for determining the freshness of rice.

Valley's decision rules, etc.

This standard applies to the acquisition and storage of rice, the determination and discrimination of the freshness of domestic japonica rice and japonica rice, and guides the acquisition and storage of rice.

Save. This standard does not apply to the determination and discrimination of the freshness of waxy rice.

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 1354-2009 Rice

GB/T 5491 Inspection of food and oil materials, sample method GB/T 6682 Analytical laboratory water specifications and test methods GB/T 20569 Rice storage quality judgment rules

3 Terms and definitions

The following terms and definitions apply to this document.

Freshness

The value of rice freshness measured under the specified experimental conditions indicates the freshness of the sample to be tested. The higher the freshness value, the fresher the rice;

The more rice is not fresh.

Fresh rice freshpaddy Paddy rice that was normally harvested in the year or rice with low quality and nitrogen storage. Rice that meets the criteria for fresh rice in this standard.

4 Principle

After the rice is unshelled, the rice is ground into the specified processing precision grade (the grade 3 processing precision specified in GB 1354-2009).

The colorant reaction, according to the different freshness of the rice, the amount of aldehydes and ketones contained in the rice, showing different color characteristics, by spectral analysis the difference in color gives the freshness value of the rice.

5 Reagents and materials

Unless otherwise specified, the experimental water should meet the specifications of the third grade water in GB/T 6682.

Developer 1). A special display agent formulated with bromothymol blue and ethanol solution.

1) The developer was developed by Beijing Dongfang Fude Technology Development Center. This information is provided for the convenience of users of this standard, not for the test.

Approval of the agent. Other developers that achieve the same results can be used.