Method for analyzing protein nitrogen content of milk powder

An analytical method and protein nitrogen technology, applied in the field of protein detection, can solve problems such as time-consuming, cumbersome, limited application scope, etc., and achieve the effects of low environmental conditions, high measurement accuracy, and high degree of automation

Inactive Publication Date: 2007-10-24
CHINA AGRI UNIV
View PDF0 Cites 8 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Therefore, for some samples (such as dairy products), tedious and time-consuming sample pretreatment is necessary to ensu

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for analyzing protein nitrogen content of milk powder

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0025] (1) Prepare 10M potassium hydroxide solution or sodium hydroxide solution, 25% (m / v) potassium tartrate solution and 4% (m / v) copper sulfate pentahydrate solution respectively.

[0026] (2) Preparation of biuret reagent. In a 1000mL volumetric flask, first add 800mL of distilled water, then add 10mL of potassium hydroxide solution or sodium hydroxide solution of the above concentration and 20mL of 25% potassium sodium tartrate solution, and add 4% CuSO dropwise under vigorous stirring. 4 ·5H 2 O solution is about 30mL, then add distilled water to 1000mL constant volume, that is to prepare the biuret reagent. This reagent can be used for a long time, but it should be sealed and stored. If precipitation occurs, it should be re-prepared.

[0027] (3) Prepare 10% trichloroacetic acid solution according to m / v concentration.

[0028] (4) Prepare the chromogenic solution of the standard sample and the sample to be tested. The specific process is: each weigh 6 kinds of milk...

Embodiment 2

[0033] (1) Prepare 5M potassium hydroxide solution or sodium hydroxide solution, 15% (m / v) potassium tartrate solution and 2% (m / v) CuSO 4 ·5H 2 O solution

[0034] (2) Preparation of biuret reagent: In a 500mL volumetric flask, first add 400mL of distilled water, then add 5mL of potassium hydroxide solution or sodium hydroxide solution of the above-mentioned concentration and 10mL of the above-mentioned potassium sodium tartrate solution, and add the above-mentioned CuSO 4 ·5H 2O solution 15mL, then add distilled water to 500mL constant volume, that is, the preparation of biuret reagent. This reagent can be used for a long time, but it should be sealed and stored. If precipitation occurs, it should be re-prepared.

[0035] (3) Prepare 10% trichloroacetic acid solution according to m / v concentration.

[0036] (4) Prepare the chromogenic solution of the standard sample and the sample to be tested. The specific process is: each weigh 6 kinds of milk powder with known protei...

Embodiment 3

[0039] (1) Prepare 10M potassium hydroxide solution or sodium hydroxide solution, 25% (m / v) potassium tartrate solution and 4% (m / v) anhydrous copper sulfate solution respectively.

[0040] (2) Preparation of biuret reagent. In a 1000mL volumetric flask, first add 800mL of distilled water, then add 10mL of potassium hydroxide solution or sodium hydroxide solution of the above concentration and 20mL of 25% potassium sodium tartrate solution, and add 4% CuSO dropwise under vigorous stirring. 4 ·5H 2 O solution is about 30mL, then add distilled water to 1000mL constant volume, that is to prepare the biuret reagent. This reagent can be used for a long time, but it should be sealed and stored. If precipitation occurs, it should be re-prepared.

[0041] (3) Prepare 40% trichloroacetic acid solution according to m / v concentration.

[0042] (4) Prepare the chromogenic solution of the standard sample and the sample to be tested. The specific process is: each weigh 6 kinds of milk po...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a milk powder protein nitrogen content analysis method belonging to protein check technique. Based on the chromatometry theory combined with that trichloroacetic acid can deposit protein and biuret can make protein into violet complex compound, that the sample with different protein contents via trichloroacetic acid can deposit the protein nitrogen, and the protein nitrogen under alkali condition can form bluish violet complex compounds with different color degrees via the biuret agent, and the chromatic value is linearly correlative with the protein content, the invention uses a computer software automatic analysis to obtain the value to be compared with the absorbance tested by a spectrophotometer, to calculate out the protein content. The invention uses general computer and scanner to replace special lab precision device as spectrophotometer, with the processes as accuracy, time, and cost test but without artificial standard curvature drafting, to make operation quick and simple, save device, reduce cost, and reduce condition demand, without pollution, while the invention can be used to detect milk powder in batch.

Description

technical field [0001] The invention belongs to protein detection technology, in particular to a milk powder protein nitrogen content analysis method completed by using milk powder protein determination software to automatically draw a standard curve for image analysis and color development of a solution after a biuret reaction. Background technique [0002] There are many methods available for protein determination. It can be deduced by using its physical properties, such as refractive index, specific gravity, ultraviolet absorption, etc.; it can also be calculated by using chemical methods, such as nitrogen determination, biuret reaction, Folin-phenol reagent reaction, and dye binding reaction. [0003] It is the most basic and most commonly used detection method at present by measuring the total nitrogen content and then converting the protein content from the total nitrogen content. Among them, the Kjeldahl method is considered to be one of the most accurate and conveni...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): G01N21/78G01N21/17G01N33/68
Inventor 侯彩云陈婧祝晓芳牛巍孙建平石文贞傅泽田张健
Owner CHINA AGRI UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap