Establishment and evaluation of a Barley starch isolation method with focus on representability
Cereal starch isolation Barley starchStarch recoveryStarch purityAmylose-Amylopectin ratioB granulesChemical deproteinisationToluene shakingProteinase K
The high viscosity of barley material makes starch isolation problematical using regular methods established for cereals. An adjusted starch isolation method has been set up for barley, based on fractionation and purification. The focus is on attaining truly representative isolates of six flour samples selected for widely differing characteristics within the research program BarleyFunFood (BFF). Beside establishment of the method, this diploma work aspires to serve the BFF with isolated material of sufficient yield valid for further starch characterisation. A pre study was conducted evaluating available wet mixing equipment, experimental conditions and mode of procedure. The yield and purity of isolates of the BFF flours were determined to 55.7-72.2% and 61.0-76.4% respectively. Due to an error in the procedure, that partly explains the poor results, one of the samples was isolated de novo resulting in an increase of the yield from 59.7 to 96.2%. Additionally, the amylose-amylopectin ratios were determined to approximately 2/99 in a waxy type, 41/59 in one high-amylose type and 30/70 in remaining varieties. New isolations are suggested to be carried out prior to further analysis of the remaining flours to achieve higher representability.