1 Scope
This standard specifies the determination method for the content of reducing sugar in foods.
Method I and Method II in this standard are applicable to the determination of reducing sugar content in foods.
Method III in this standard is applicable to the determination of reducing sugar content in wheat flour.
Method IV in this standard is applicable to the determination of reducing sugar content in sugar beet root.
Method I: Direct Titrimetric Method
2 Principle
After removing the protein in the specimen, titrate the calibrated alkaline cupric tartrate solution (which has been calibrated with reducing sugar standard solution) under heating conditions with methylene blue as the indicator, and then calculate the reducing sugar content according to the consumed volume of sample solution.
3 Reagents and Materials
Unless otherwise specified, analytically-pure reagents and Grade-III water (defined in GB/T 6682) are adopted for the purpose of this method.
3.1 Reagents
3.1.1 Hydrochloric acid (HCl).
3.1.2 Copper sulfate (CuSO4?5H2O).
3.1.3 Methylene blue (C16H18ClN3S?3H2O).
3.1.4 Sodium potassium tartrate (C4H4O6KNa?4H2O).
3.1.5 Sodium hydroxide (NaOH).
3.1.6 Zinc acetate [Zn(CH3COO)2?2H2O].
Contents
Foreword I
1 Scope
2 Principle
3 Reagents and Materials
4 Instruments and Apparatus
5 Analysis Steps
6 Expression of Analysis Result
7 Precision
8 Other
9 Principle
10 Reagents and Materials
11 Instruments and Apparatus
12 Analysis Steps
13 Expression of Analysis Result
14 Precision
15 Other
16 Principle
17 Reagents
18 Instruments and Apparatus
19 Analysis Steps
20 Expression of Analysis Results
21 Precision
22 Principle
23 Reagents and Materials
24 Instruments and Apparatus
25 Analysis Steps
26 Expression of Analysis Results
27 Precision
28 Other
Appendix A
