Food Protein Analysis
No description yet. This curated deck is ready for daily study.
Card preview (8)
what is food protein analysis
the use of reliable quantitative methods to determine the total protein content of foods and food ingredients
why do we need food protein analysis
to establish nutrient values/ content to regulate safety specifications to avoid risks to the public health
what are the methods of food protein analysis
Kjeldahl method and Dumas method - nitrogen based methods that rely on total nitrogen determination to estimate protein content
what are the advantages of the Kjeldahl method and Dumas method
• cheap and fast
what are the disadvantages of the Kjeldahl method and Dumas method
• cannot distinguish protein-based nitrogen from non-protein based nitrogen
what is the Kjeldahl method
• quantifies the total protein content of foods by direct nitrogen measurement and subsequent multiplication by a conversion factor of 6.25 The total organic nitrogen content is analysed by: • digestion to convert nitrogen to ammonium sulfate • neutralisation with alkali to convert ammonium sulphate to free ammonia • distillation of ammonia to boric acid • titration of excess boric acid with alkali • takes 3 hours • the use of sulfuric acids presents safety concerns
what is the Dumas method
• total nitrogen is measured by gas chromatography and the nitrogen protein conversion factors are used to calculate the total protein content • simple, cheap, safe • takes 3 minutes
Name some other emerging methods of food protein analysis
• antibody based methods • enzyme-linked immunosorbent assays • chromatographic methods • electrophoretic methods • mass spectrophotometry