University of Natural Resources and Life Sciences, Vienna (BOKU) - Research portal
Gewählte Master / Diploma Thesis:
Lydia Gamper
(2022):
Chemische und rheologische Charakterisierung von Mahlfraktionen aus alternativen
Getreidearten.
Master / Diploma Thesis - Institut für Lebensmitteltechnologie,
BOKU-Universität für Bodenkultur,
pp 99.
UB BOKU
obvsg
- Abstract:
- The aim of this work was to characterize sorghum chemically and rheologically in order to find out to what extent sorghum can be used as a possible alternative to conventional cereals in baking. For this purpose, the Amorik variety was ground using various grinding methods. The first variant was ground as a dry flake crusher and the second variant with a stone mill. At the stone mill, the grain was ground very finely so that it was broken down into its individual components. The third variant of the flour is a mixture of the two grinding systems. All three types of flour have been divided into different particle sizes. In order to determine the baking quality of the sorghum fractions, baking experiments were carried out in combination with wheat flour W700 with subsequent physical analyzes. According to the analyzes, there were obvious differences. The protein content in the mixture of squeezer and stone mill was highest in the fraction above 400μm. The smallest amount of protein was found in the finest fraction (<180 μm) of the drying flake crusher. This can be explained by the fact that the protein is mainly in the outer part of the shell. Most of the starch can be found inside the grain, i.e. in the endosperm. The highest starch values were therefore found in the whole grain of the mixture of crushers and stone mills. When measuring the viscosity of the mixture of squeezer and stone mill, only the measurement of whole grain gave a classic curve. Only when silver nitrate was added, did the fractions also have a viscosity curve. Since silver nitrate inhibits the alpha-amylase activity, which inhibits starch degradation, it was assumed that the starch could no longer be degraded as a result of the inhibition. Although the highest proportion of starch was in the whole grain, this turned out not to be a decisive factor for the quality of the baked goods.
- Beurteilende*r: Schönlechner Regine
- 1.Mitwirkender: Rumler Rubina