GB/T 5009.157-2003 Determination of organic acids in food

This standard specifies the high performance liquid chromatography method for the determination of organic acids (tartaric acid, malic acid, citric acid, succinic acid) in foods. This standard is applicable to the determination of organic acid content in fruits, vegetables, their products, beverages and other foods. The detection limits of this method are: tartaric acid 0.1μg/mL, malic acid 0.3μg/mL, citric acid 0.51μg/mL, succinic acid 2.01μg/mL. GB/T 5009.157-2003 Determination of organic acids in food GB/T5009.157-2003 Standard download decompression password: www.bzxz.net

National Standard of the People's Republic of China
GB/T5009.157-—2003
Determinatioe ef organlc acid in food
Determinatioe ef organlc acid in food
Published on August 11, 2003
Ministry of Health of the People's Republic of China
National Standardization Administration of China
2004-01-01Implementation
GB/T 5009.157-2003
This standard was proposed and managed by the Ministry of Health of the People's Republic of China. The responsible drafting unit of this standard is the School of Public Health of Shuhan Medical University. This standard was mainly drafted by: Cha Yuanqing, Wang Guangbian, Yang Qing, Yang Yuan1 Scope
Determination of organic acids in food
GB/T 5039.157.-2003
This standard specifies the high performance liquid chromatography method for determining organic acids (tartaric acid, tartaric acid, succinic acid, butyric acid) in food. This standard is applicable to the determination of narrow organic acids in foods such as fruits and their preparations, beverages, etc. The detection limit of this method is: tartaric acid 0.1g/mL. Malic acid 0.3g/m., tanoic acid 1.5/ml, 2./ml
2 Principle
The samples were prepared by filtration with 0.3m iontophoresis and then washed with (NH4HPO4-IT2.7) aqueous solution. The samples were separated by commercial subtraction chromatography in C. 200 nm. The samples were inspected by external microanalyzer at 210 nm. The organic content was determined by peak height or peak area. 3 Reagents
All reagents used in this method were analytically pure. The test water was heavy or isocyanate water. After vacuum filtration with 45m membrane, 3.150 tablets of ethanol were selected.
3.21ml/L diammonium sulfate was condensed,
3.31nl/l phosphoric acid.
3.4 ​​Organic standard solution, weigh 2.5000g of tartaric acid, benzoic acid, citric acid: 0.1000g of succinic acid: dilute with water, dilute to ≤0mL, the concentration of tartaric acid, malic acid and citric acid is 10.0mg/mL, butyric acid is 2.0mg/mL, this is the standard solution, standard method, take 5.60mL of each standard chain in a 50mL volumetric flask and dilute to the concentration with ultrafiltered water. tartaric acid, benzoic acid, if the acid concentration is 1.g/mL, butyric acid/mL.4 Instruments
4.1 Free of crushing machine.
4.2 Combustion,
4,3 High-resolution spectrometer, ketone can be detected by external crown. 4.4 Aldehyde meter.
4.5 Filter head, 5.um fiber filter membrane. 5 Analysis steps
5.1 Sample processing
5.1.1 Body sample: Take 50g of sample and put it into tissue crusher, add 1m0% ethanol, and add 1u. Take quantitative slurry (equivalent to 5g sample) and centrifuge at 3000z/sin for 20min to separate the upper liquid, transfer it into 50ml medium, add 80% ethanol twice, centrifuge for 15min each time, high centrifuge for 10min. Close the upper liquid, add 5% ethanol to weigh the mixture, filter it, and this liquid is the final product. Take 5.00mL of the extract and evaporate the 76% ethanol to dryness, transfer to a chromatograph tube, add 0.2mL/L phosphate (H.PO.) and adjust the volume to 10mL with heavy distilled water. Fill the 0.3mL filter head with the sample through the filter bag as described above, and use it for high efficiency phase analysis. 37
CB/T 5009.157—2003
5.1.2 Liquid sample: accurately remove 5.00TL sample (if the sample contains two kinds of chemicals, heat it first; if the sample contains human T. anhydrous color, add human amine powder first and heat it in a 70℃ water bath for decolorization, centrifuge the sample at 30001/in for 13min, and then take the supernatant), add 0.2ml.1mol/1. phosphoric acid + dilute with water to 10mL, filter through 0.3Am filter membrane, and filter for analysis. 6.1 Chromatographic conditions
Pre-column: C column, a μm4, filter mmx3 mmim Analytical standard: c note, 5an.4.6mtnx50mm. Then, 0.U1 mol/L diammonium hydrogen phosphate, use 1 mol/L lysine to pH=2. 7C, degas with supernatant before use. Shen Jian Shang mL/min
Injection volume. 2Cpl..
Labor external detector wavelength: 210nml.
B.2 Preparation of standard curve
Use 0.50, 1.00, 2.00, 3.00, 10.00mL of the standard, add C.2mL1mol/L ether water to dilute to 10mL, meet. Inject 20L, draw a bee height or whole area at 210m, each Repeat the injection 2-3 times and take the half mean. With the concentration of organic acid as the horizontal coordinate and the mean of the peak height or peak area as the vertical coordinate, draw the standard curve or obtain the regression equation through linear regression.
6.3 Sample determination
Under the same chromatographic conditions as those for drawing the standard curve, inject the sample solution into the chromatogram and calculate the concentration of organic acid in the sample according to the standard curve or linear regression equation. 7 Result calculation
The concentration of organic acid in the sample is calculated according to the following formula: Sample.
solid sample,
where:
: the content of organic acid in the sample is in whole gram per kilogram (gram per liter) mg/kkg/ The concentration of organic acid in the sample is obtained by the standard curve or linear equation, the unit is microgram per liter (\g) Vi-
The volume of the sample is measured in liters (mL) The solid test piece is the total volume of the extracted solid sample used for analysis, the unit is liters (ml), the sample for analysis is The unit of the sample is the mass of the sample, in grams (g).
8 Precision
The absolute difference between two independent results obtained under reproducible conditions shall not exceed the arithmetic mean. 9 Other
The chromatogram of the standard solution of organic acids is shown in Figure 1. 316 bzxZ.net
[——Reduced sodium bicarbonate,
2-—Prohibited membrane:
-acetic acid;
|Can be replaced;
5--T-alcohol.
Figure 1 Standard filtration chromatogram
GA/T 5009. 157--2003
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