1 Scope
This standard specifies the methods for determination of acidity in raw milk and milk products, starch and derived products and grain and produce.
In this standard, Method I is applicable to the determination of acidity in raw milk and milk products, starch and derived products, and grain and produce; Method II is applicable to the determination of acidity in milk powder; Method III is applicable to the determination of acidity in milk and other milk products.
Method I Phenolphthalein Indicator Method
2 Principle
After the specimen is treated, titrate it to neutral with 0.1000mol/L sodium hydroxide standard solution with phenolphthalein as indicator and then determine the acidity in specimen through calculation according to the volume of consumed sodium hydroxide solution.
3 Reagent and Materials
Unless otherwise specified, analytically-pure reagents and Class-III water (defined in GB/T 6682) are adopted for the purpose of this method.
3.1 Reagents
3.1.1 Sodium hydroxide(NaOH).
3.1.2 Cobalt sulfate hepathydrate (CoSO4•7H2O).
3.1.3 Phenolphthalein.
3.1.4 95% ethanol.
3.1.5 Ethyl ether.
3.1.6 Nitrogen: with the purity of 98%.
3.1.7 Trichloromethane (CHCl3).
3.2 Reagent preparation
3.2.1 Sodium hydroxide standard solution(0.1000mol/L)
Foreword I
1 Scope
2 Principle
3 Reagent and Materials
4 Instruments and Apparatus
5 Analysis Procedures
6 Expression of Analysis Result
7 Precision
8 Principle
9 Reagents and Materials
10 Instruments and Apparatus
11 Analysis Steps
12 Expression of Analysis Result
13 Precision
14 Principle
15 Reagents and Materials
16 Instruments and Apparatus
17 Analysis Steps
18 Expression of Analysis Result
19 Precision
Standard
GB 5009.239-2016 National Food Safety Standard -Determination of Acidity in Foods (English Version)
Standard No.
GB 5009.239-2016
Status
valid
Language
English
File Format
PDF
Word Count
5500 words
Price(USD)
80.0
Implemented on
2017-3-1
Delivery
via email in 1 business day
Detail of GB 5009.239-2016
Standard No.
GB 5009.239-2016
English Name
National Food Safety Standard -Determination of Acidity in Foods
1 Scope
This standard specifies the methods for determination of acidity in raw milk and milk products, starch and derived products and grain and produce.
In this standard, Method I is applicable to the determination of acidity in raw milk and milk products, starch and derived products, and grain and produce; Method II is applicable to the determination of acidity in milk powder; Method III is applicable to the determination of acidity in milk and other milk products.
Method I Phenolphthalein Indicator Method
2 Principle
After the specimen is treated, titrate it to neutral with 0.1000mol/L sodium hydroxide standard solution with phenolphthalein as indicator and then determine the acidity in specimen through calculation according to the volume of consumed sodium hydroxide solution.
3 Reagent and Materials
Unless otherwise specified, analytically-pure reagents and Class-III water (defined in GB/T 6682) are adopted for the purpose of this method.
3.1 Reagents
3.1.1 Sodium hydroxide(NaOH).
3.1.2 Cobalt sulfate hepathydrate (CoSO4•7H2O).
3.1.3 Phenolphthalein.
3.1.4 95% ethanol.
3.1.5 Ethyl ether.
3.1.6 Nitrogen: with the purity of 98%.
3.1.7 Trichloromethane (CHCl3).
3.2 Reagent preparation
3.2.1 Sodium hydroxide standard solution(0.1000mol/L)
Contents of GB 5009.239-2016
Foreword I
1 Scope
2 Principle
3 Reagent and Materials
4 Instruments and Apparatus
5 Analysis Procedures
6 Expression of Analysis Result
7 Precision
8 Principle
9 Reagents and Materials
10 Instruments and Apparatus
11 Analysis Steps
12 Expression of Analysis Result
13 Precision
14 Principle
15 Reagents and Materials
16 Instruments and Apparatus
17 Analysis Steps
18 Expression of Analysis Result
19 Precision