Analytical methods

Analytical methods at the TTE as part of research projects

• Determination of dry matter or water content
  › classical drying method
  › freeze drying

• Fraction of inorganic constituents
  › ash
  › hydrochloric acid insoluble ash (indicator for determination of digestibility)
  › titanium dioxide (indicator for determination of digestibility)
  › microwave digestion for analysis of minerals and trace elements
  › determination of minerals (Na, K, Ca, Mg) and trace elements (Zn, Cu, Fe, Se, Mn) by AAS and phosphorus by UV-Vis photometer
  › determination of elements (Na, K, Ca, Mg, P, S, Zn, Cu, Fe, Se, Mn, Co, Ni, Cr, Mo, Pb, Cd) by ICP-MS (cooperation with the Institute of Bioanalytics and Agro-Metabolomics of the Department IFA-Tulln)
  › phytate content

• Fraction of nitrogenous compounds
  › total nitrogen by Kjeldahl or Dumas
  › ammonia (photometric determination)
  › biogenic amines by HPLC
  › amino acids by HPLC (excl. Trp, Met, Cys)
  › protein fractionation according to CNCPS
  › protein determination in solutions (Bradford method)
  › protein solubility in KOH and water
  › reactive lysine

• Fraction of lipids
  › ether extract or ether extract following acid hydrolysis
  › profile of medium and long chain fatty acids by GC
  › vitamin E by HPLC
  › carotenoids (total carotenoids by photometric method, individual carotenoids by HPLC)
  › oxidation stability of fats and oils

• Fraction of carbohydrates
  › soluble carbohydrates (sugar, starch)
  › fibre (crude fibre, NDF, ADF, ADL, TDF incl. SDF/IDF)
  › carbohydrate fractionation according to CNCPS
  › water holding capacity, water binding capacity, swelling capacity of high-fibre feeds
  › buffering capacity of high-fibre feeds

• Energy
  › gross energy by bomb calorimeter
  › estimation of ME content in roughage (ELOS)

• n-alkanes by GC

• Determination of lead substances for boar taint (skatole, androstenone) in pork and fat
   
• Oxidative stability of animal tissue
  › activity of antioxidant enzymes (glutathione peroxidase, superoxide dismutase, catalase)
  › lipid peroxidation (TBARS)
  › total antioxidant capacity (e.g. ABTS, DPPH)

• Histology
  › staining methods: HE, goblet cell staining (AB-PAS), apoptosis staining (TUNEL), IgA producing cells
  › intestinal morphology
  › laser assisted microdissection of tissues and cells

• Molecular biology
  › gene expression analysis
  › species identification
   
• Gut microbiota
  › Characterisation of the gut microbiota (cooperation with the Department of Food Science and Technology)
  › Microbial metabolites
       › short chain fatty acids (SCFA) by GC
       › lactic acid (photometric determination)
       › ammonia (photometric determination)
       › biogenic amines by HPLC
   
• Physical methods
  › rheology (texture profile analysis, shear force, etc.) of animal tissue
  › breaking strength (egg, bones)
  › colour (L*a*b*) of meat, egg (yolk), egg shell, etc.
  › water holding capacity of meat
  › preparation loss and drip loss of meat
  › particle size distribution of feed
  › viscosity of feed and digesta
  › pH value
   
• Sensory analyses
  › discrimination test
  › classification tests
  › ranking test
   
• Polyphenols
  › total phenols
  › condensed tannins
  › protein precipitation capacity of polyphenols

Sample matrices

• food
• feed
• digesta
• faeces
• urine
• blood
• animal tissue samples