GB/T 5527-2024 PDF English
Price & Delivery
US$215.00 · In stock · Download in 9 secondsGB/T 5527-2024: Animal and vegetable fats and oils - Determination of refractive index
Delivery: 9 seconds. True-PDF full-copy in English & invoice will be downloaded + auto-delivered via email. See step-by-step procedure
Status: Valid
GB/T 5527: Historical versions
| Standard ID | USD | BUY PDF | Delivery | Standard Title (Description) | Status |
| GB/T 5527-2024 | 215 | Add to Cart | Auto, 9 seconds. | Animal and vegetable fats and oils - Determination of refractive index | Valid |
| GB/T 5527-2010 | 160 | Add to Cart | Auto, 9 seconds. | Animal and vegetable fats and oils -- Determination of refractive index | Valid |
| GB/T 5527-1985 | 199 | Add to Cart | 2 days | Inspection of vegetable oils--Methods for determination of refractive index | Obsolete |
Click to Preview this PDF
GB/T 5527-2024: Animal and vegetable fats and oils - Determination of refractive index
---This is an excerpt. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.), auto-downloaded/delivered in 9 seconds, can be purchased online: https://www.ChineseStandard.net/PDF.aspx/GBT5527-2024GB NATIONAL STANDARD OF THE PEOPLE’S REPUBLIC OF CHINA ICS 67.200.10 CCS X 14 Replacing GB/T 5527-2010 Animal and vegetable fats and oils - Determination of refractive index (ISO 6320.2017, MOD) Issued on: OCTOBER 26, 2024 Implemented on: MAY 1, 2025 Issued by. Standardization Administration of China; State Administration for Market Regulation.
Table of Contents
Preface... 3 1 Scope... 5 2 Normative References... 5 3 Terms and Definitions... 5 4 Principle... 6 5 Reagents... 6 6 Abbe Refractometer Method (Method 1)... 6 7 Automatic Refractometer Method (Method 2)... 9 Appendix A (Normative) Interlaboratory Test Results... 12 References... 13 Animal and vegetable fats and oils - Determination of refractive index1 Scope
This document specifies the Abbe refractometer method and the automatic refractometer method for the determination of the refractive index of animal and vegetable oils. This document is applicable to animal and vegetable oils, but not to the determination of the refractive index of milk fat and milk fat products.2 Normative References
The following referenced documents are indispensable for the application of this document. For dated references, only the edition with the stated date applies. For undated references, the latest edition of the referenced document (including any amendments) applies. GB/T 6379.1 Accuracy (Correctness and Precision) of Measurement Methods and Results - Part 1.General Principles and Definitions (GB/T 6379.1-2004, ISO 5725- 1.1994, IDT) GB/T 6379.2 Accuracy (Correctness and Precision) of Measurement Methods and Results - Part 2.Fundamental Methods for Determining the Repeatability and Reproducibility of Standard Measurement Methods (GB/T 6379.2-2004, ISO 5725- 2.1994, IDT) GB/T 15687 Animal and Vegetable Oils - Preparation of Test Samples (GB/T 15687- 2008, ISO 661.2003, IDT)3 Terms and Definitions
The following terms and definitions apply to this document. 3.1 Refractive index (of a medium) The ratio of the speed of light of a given wavelength in a vacuum to its speed in that medium. Note 1.In practical applications, the speed of light in air is used instead of that in a vacuum. Unless otherwise specified, the wavelength adopted is the average wavelength of the sodium D line (589.6 nm). Note 2.The refractive index of a substance varies with the wavelength of the incident light and temperature, denoted as, in which “t” is the temperature in degrees Celsius.4 Principle
At a specified temperature, use a suitable refractometer to determine the refractive index of a liquid sample.5 Reagents
Only analytical grade reagents shall be used. Distilled water, deionized water, or water of equivalent purity shall be used in the laboratory. 5.1 Ethyl laurate. The purity is suitable for refractive index determination and the refractive index is known. 5.2 Hexane or other suitable solvents (such as petroleum ether, acetone, etc.). It is used for cleaning the prism of the refractometer.6 Abbe Refractometer Method (Method 1)
6.1 Instruments 6.1.1 Refractometer. Refractive index measurement range. nD = 1.300 to nD = 1.700, refractive index readable to ±0.0001. 6.1.2 Light source. Sodium vapor lamp. If the refractometer is equipped with an achromatic compensation system, white light may also be used. 6.1.3 Glass plate. With known refractive index. 6.1.4 Circulating water bath device. With circulating pump and constant temperature control device, temperature control accuracy is ±0.1℃. 6.1.5 Constant temperature water bath. When the sample is solid, it can maintain the required temperature for measurement. 6.2 Sampling The samples received by the laboratory shall be representative, and shall not have been damaged or altered during transportation or storage. Sampling is not covered in this document; GB/T 5524 is recommended. 6.3 Sample Preparation Prepare the sample according to GB/T 15687.The sample used for refractive index measurement shall be a dried and filtered oil sample. For solid samples, prepare the sample according to GB/T 15687.Then, transfer it to a suitable container. Place it in a constant temperature water bath (6.1.5). The water bath temperature is set to the temperature at which the sample is to be measured. Leave it for sufficient time to allow the sample temperature to stabilize. 6.4 Operating Procedure 6.4.1 Instrument Calibration According to the operating procedures in the instrument manual, by measuring the refractive index of the glass plate (6.1.3) or measuring the refractive index of ethyl laurate (5.1), calibrate the refractometer (6.1.1). 6.4.2 Measurement 6.4.2.1 Measurement Conditions Select one of the following temperature conditions to measure the refractive index of the sample. a) 20℃ is applicable for oils that are completely liquid at this temperature; b) 40℃ is applicable for oils that do not completely melt at 20℃ but completely melt at 40℃; c) 50℃ is applicable for oils that do not completely melt at 40℃ but completely melt at 50℃; d) 60℃ is applicable for oils that do not completely melt at 50℃ but completely melt at 60℃; e) 80℃ or above is used for other oils, such as fully hardened fats or waxes. 6.4.2.2 Measurement Procedure 6.4.2.2.1 Hot water from the water bath (6.1.4) is circulated through the refractometer to maintain the refractometer prism at the constant temperature t required for the measurement. 6.4.2.2.2 Use precision thermometer to measure the temperature of the water flowing out of the refractometer. Before measurement, lower the movable part of the prism to a horizontal position. Clean the prism surface first with a soft cloth, then with a cotton 6.6.2 Repeatability Within the same laboratory, by the same operator using the same equipment, following the same test method, the absolute difference between two independent test results obtained from testing the same object independently within a short period shall not exceed the repeatability limit (r) in Table A.1 for more than 5% of cases. If it must verify whether the repeatability requirement is met, two single-sample determinations shall be carried out according to the analysis steps in 6.4.1 or 6.4.2. 6.6.3 Reproducibility In different laboratories, by different operators using different equipment, following the same test method, the absolute difference between two independent test results obtained from testing the same object independently shall not exceed the reproducibility limit (R) in Table A.1 for more than 5% of cases. 6.7 Test Report The test report must indicate. -- All relevant information required for the test sample; -- If the sampling method is known, indicate it; -- The test method adopted and the referenced standards; -- Any aspects not specifically described in this document, or deemed optional, as well as all operational details that may affect the results.7 Automatic Refractometer Method (Method 2)
7.1 Instruments 7.1.1 Automatic refractometer. Refractive index measurement range is nD = 1.300 to nD = 1.700, and the refractive index is readable to ±0.0001.Built-in constant temperature controller. with selectable temperature control range of 20℃~99.9℃, and accuracy of 0.01℃. 7.1.2 Constant temperature water bath. When the sample is solid, it can maintain the temperature required for the measurement. 7.2 Sampling Same as 6.2. 7.3 Sample Preparation ......Source: Above contents are excerpted from the full-copy PDF -- translated/reviewed by: www.ChineseStandard.net / Wayne Zheng et al.
