GB 5009.299-2024 PDF English
US$125.00 · In stock · Download in 9 secondsGB 5009.299-2024: National food safety standards--Determination of lactoferrin in food Delivery: 9 seconds. True-PDF full-copy in English & invoice will be downloaded + auto-delivered via email. See step-by-step procedureStatus: Valid
| Standard ID | Contents [version] | USD | STEP2 | [PDF] delivery | Name of Chinese Standard | Status |
| GB 5009.299-2024 | English | 125 |
Add to Cart
|
0-9 seconds. Auto-delivery
|
National food safety standards--Determination of lactoferrin in food
| Valid |
Excerpted PDFs (Download full copy in 9 seconds upon purchase)PDF Preview: GB 5009.299-2024
GB 5009.299-2024: National food safety standards--Determination of lactoferrin in food---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/GB5009.299-2024
GB
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
National food safety standard - Determination of lactoferrin
in food
Issued on. FEBRUARY 08, 2024
Implemented on. AUGUST 08, 2024
Issued by. National Health Commission of the People’s Republic of China;
State Administration for Market Regulation.
Table of Contents
1 Scope... 3
2 Principle... 3
3 Reagents and materials... 3
4 Instruments and equipment... 5
5 Analysis procedure... 5
6 Expression of analysis results... 7
7 Precision... 7
8 Others... 7
Annex A Liquid chromatogram of bovine lactoferrin standard solutions... 8
Annex B Heparin affinity column validation method... 9
National food safety standard
Determination of lactoferrin in food
1 Scope
This Standard specifies the high-performance liquid chromatography method for the
determination of lactoferrin in food.
This Standard applies to the determination of bovine lactoferrin content in pasteurized
milk, prepared milk, milk-containing beverages, prepared milk powder and milk-based
infant formula.
This Standard does not apply to the determination of bovine lactoferrin in flavored
fermented milk and soy-based infant formula.
2 Principle
The bovine lactoferrin in the sample is extracted with phosphate buffer, enriched and
purified with a heparin affinity column, then separated by a reversed-phase high-
performance liquid chromatography column, detected with a UV detector at 280 nm,
and quantified by the external standard method.
3 Reagents and materials
Unless otherwise stated, the reagents used in this method are of analytical regent, and
the water is Grade 1 water specified in GB/T 6682.
3.1.1 Acetonitrile (CH3CN). chromatographically pure.
3.1.5 Disodium hydrogen phosphate (Na2HPO4).
3.2 Preparation of reagents
3.2.1 Phosphate buffer I. Weigh 7.1 g of disodium hydrogen phosphate and 58.4 g of
sodium chloride, add 900 mL of water to dissolve, adjust the pH to 8.0 ± 0.2 with
phosphoric acid, add water to make the volume to 1000 mL, and freshly prepare each
time before use.
3.3 Reference material
Bovine lactoferrin reference material (CAS number. 146897-68-9). purity ≥ 95 %, iron
content ≤ 35 mg/100 g, or a reference material certified by the country and awarded a
reference material certificate.
3.4 Preparation of standard solutions
3.4.1 Bovine lactoferrin standard stock solution (5.0 mg/mL). Weigh 50 mg (accurate
to 0.1 mg) of bovine lactoferrin reference material, dissolve it in water, transfer to a 10
mL volumetric flask and dilute to the mark, and mix well. Store at 0℃ ~ 4 ℃, it can be
stored for 3 months.
3.5 Materials
3.5.1 Heparin affinity column. 1 mL, column capacity ≥ 2 mg, or one with equivalent
performance (see Annex B for verification method).
3.5.2 Filter membrane, aqueous phase, 0.45 μm.
3.5.3 Aqueous syringe filter. polyethersulfone material, 0.45 μm.
4 Instruments and equipment
4.1 High-performance liquid chromatograph. equipped with a UV detector or
equivalent.
4.5 Vortex oscillator.
4.6 Constant temperature water bath.
4.7 Solid phase extraction column device.
5 Analysis procedure
5.1 Pre-treatment of samples
5.1.1 Preparation of samples
Take at least 200 g of a representative sample. If it is a liquid sample, shake well and
store it in a container as a sample, store it at 0 ℃ ~ 4 ℃ for later use. If it is a solid
sample, mix well and store it in a container as a sample, store it dry at room temperature
for later use.
5.1.2 Extraction of samples
5.1.3 Purification of samples
Before use, add 5.0 mL of phosphate buffer II to activate the heparin affinity column.
Accurately pipette 10.0 mL of the above sample solution to pass through the column,
control the flow rate at 1 mL/min ~ 3 mL/min.
5.2 Instrument reference conditions
5.2.1 Chromatographic column. C4, 5 μm, 300Å, 250 mm × 4.6 mm (inner diameter) or
equivalent.
5.3 Plotting of standard curve
Respectively inject the bovine lactoferrin standard series working solutions into the
high-performance liquid chromatograph, determine the corresponding peak areas, and
plot a standard curve with the concentrations of bovine lactoferrin in the standard
working solutions as the abscissa and the peak areas as the ordinate.
5.4 Determination of sample solution
Inject the sample solution into the high-performance liquid chromatograph to obtain the
peak area, then obtain the concentration of bovine lactoferrin in the sample according
to the standard curve.
6 Expression of analysis results
The bovine lactoferrin content in the sample is calculated according to formula (1).
7 Precision
The absolute difference between two independent determination results obtained under
repeatability conditions shall not exceed 10 % of the arithmetic mean.
8 Others
When the sampling volume of the liquid sample is 5.00 g and the constant volume is
25 mL, the detection limit of the liquid sample in this method is 0.3 mg/100 g and the
quantification limit is 1 mg/100 g; when the sampling volume of the solid sample is
5.00 g and the constant volume is 50 mL, the detection limit is 2 mg/100 g and the
quantification limit is 6 mg/100 g.
Annex A
Liquid chromatogram of bovine lactoferrin standard solutions
The liquid chromatogram of bovine lactoferrin standard solutions (50.0 μg/mL) is
shown in Figure A.1.
Figure A.1 -- Liquid chromatogram of bovine lactoferrin standard solutions (50.0
μg/mL)
Annex B
Heparin affinity column validation method
B.1 Column capacity verification
Take 0.40 mL of the 5.0 mg/mL bovine lactoferrin standard stock solution and pass it
through the heparin affinity column instead of the sample solution, operate according
to 5.1.3, use a liquid chromatograph to measure the bovine lactoferrin content and
calculate its recovery rate. Test at least 2 heparin affinity columns from the same batch.
B.2 Result judgment
If the recovery rate of bovine lactoferrin is ≥ 95 %, it is a usable product.
......
Source: Above contents are excerpted from the full-copy PDF -- translated/reviewed by: www.ChineseStandard.net / Wayne Zheng et al.
Tips & Frequently Asked QuestionsQuestion 1: How long will the true-PDF of English version of GB 5009.299-2024 be delivered?Answer: The full copy PDF of English version of GB 5009.299-2024 can be downloaded in 9 seconds, and it will also be emailed to you in 9 seconds (double mechanisms to ensure the delivery reliably), with PDF-invoice. Question 2: Can I share the purchased PDF of GB 5009.299-2024_English with my colleagues?Answer: Yes. The purchased PDF of GB 5009.299-2024_English will be deemed to be sold to your employer/organization who actually paid for it, including your colleagues and your employer's intranet. Question 3: Does the price include tax/VAT?Answer: Yes. Our tax invoice, downloaded/delivered in 9 seconds, includes all tax/VAT and complies with 100+ countries' tax regulations (tax exempted in 100+ countries) -- See Avoidance of Double Taxation Agreements (DTAs): List of DTAs signed between Singapore and 100+ countriesQuestion 4: Do you accept my currency other than USD?Answer: Yes. www.ChineseStandard.us -- GB 5009.299-2024 -- Click this link and select your country/currency to pay, the exact amount in your currency will be printed on the invoice. Full PDF will also be downloaded/emailed in 9 seconds. How to buy and download a true PDF of English version of GB 5009.299-2024?A step-by-step guide to download PDF of GB 5009.299-2024_EnglishStep 1: Visit website https://www.ChineseStandard.net (Pay in USD), or https://www.ChineseStandard.us (Pay in any currencies such as Euro, KRW, JPY, AUD).
Step 2: Search keyword "GB 5009.299-2024".
Step 3: Click "Add to Cart". If multiple PDFs are required, repeat steps 2 and 3 to add up to 12 PDFs to cart.
Step 4: Select payment option (Via payment agents Stripe or PayPal).
Step 5: Customize Tax Invoice -- Fill up your email etc.
Step 6: Click "Checkout".
Step 7: Make payment by credit card, PayPal, Google Pay etc. After the payment is completed and in 9 seconds, you will receive 2 emails attached with the purchased PDFs and PDF-invoice, respectively.
Step 8: Optional -- Go to download PDF.
Step 9: Optional -- Click Open/Download PDF to download PDFs and invoice.
See screenshots for above steps: Steps 1~3 Steps 4~6 Step 7 Step 8 Step 9
|