Department of Bioactive and Functional Food Chemistry

Method toolbox

Liquid chromatography mass spectrometry

Figure 1. Sample preparation and measurement for untargeted and targeted liquid chromatography mass spectrometry.

 

High-performance liquid chromatography

Figure 2. Workflow for modified Osborne fractionation of flour proteins combined with reversed-phase high-performance liquid chromatography (RP-HPLC) and UV detection at 210 nm to reveal the typical fingerprints of the wheat albumin/globulin, prolamin and glutelin fractions.

 

Immunological techniques (ELISA, Western Blot)

Figure 3. Enzyme-linked immunosorbent assay (ELISA) plate and plots of absorbance-protein concentration curves recorded for the kit standard (black line), the reference material Prolamin Working Group (PWG)-gliadin (black dashed line), prolamins from wheat (green dotted line with open triangles), rye (blue dotted line with open diamonds) and barley (red dotted line with open squares) as well as glutelins from wheat (green line with filled triangles), rye (blue line with filled diamonds) and barley (red line with filled squares).

 

Gel electrophoresis

Figure 4. Sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE) of different wheat cultivars showing the characteristic molecular weight distribution of high-molecular-weight glutenin subunits, ω5-gliadins, ω1,2-gliadins, α-gliadins, γ-gliadins and low-molecular-weight glutenin subunits (from top to bottom).

 

Baking, rheology and texture analysis

  • Farinograph (10 g, 50 g, 300 g
  • Gluten aggregation test, gluten index, dynamic stress rheometry, viscosimetry
  • Microscale extension tests
  • Microscale baking tests (10 g of flour, automated baking line)
  • Measurement of bread volume and texture

Figure 5. Micro-scale extension tests of vital gluten samples isolated from wheat cultivars Akteur, Julius, Tommi and Winnetou as well as microbaking tests.