Protein (Nitrogen) Analysis for Liquid Milk | Application

Protein (Nitrogen) Analysis for Liquid Milk

Sample Preparation
Samples may be analyzed as received.

Instrument
5E-TCN2200 Protein Analyzer

Instrument Settings
Oxygen Flow(SV4): 3L/min
Oxygen Flow(SV5): 0.8L/min
Oxygen Flow(SV6): 0.3L/min
Main Furnace Temperature: 950 ℃
Secondly Furnace Temperature: 850 ℃
Calibration Standard: BS EN ISO 16634-1:2008
Nominal Sample Weight: 80 mg
Analysis Time: 5 minutes

Special Modifications to Unit
None

Method Approval

BS EN ISO 16634-1:2008

Food products. Determination of the total nitrogen content by combustion according to the Dumas principle and calculation of the crude protein content. Oilseeds and animal feeding stuffs standard

Procedure

1. Prepare instrument as outlined in the operator’s instruction manual (perform maintenance and leak checks, etc.).

2. Add some COM-AID in the bottom of Tin cup, then using pipette filling sample into Tin cup and get the sample weight. At last cover the sample with some COM-AID again and seal Tin cup like a drop.

3. Purging and analyze blanks until instrument is stable (nitrogen results will reach a plateau),
4. (4-5) blanks and (1-2) waste samples to condition the instrument 
5. 3 samples of calibration substance to check or carry out the calibration; 
6. Test 9 samples 
7. 2 samples of calibration substance to check the calibration; 
8. Repetition of point 5 to point 6 until all samples are processed;

Note: Do Calibrating refer to operator’s instruction manual for details.

Typical Results