Investigation of the use of sprouted grains as feedstock for directly expanded cereals [article]

Julia Krapf, Technische Universität Berlin, Eckhard Flöter
2021
The use of sprouted grains in the production of directly expanded breakfast cereals is a promising opportunity to produce health‐promoting, newly flavored, and colored products with less additive sugar. Hardly any knowledge about the effect of the variation of the sprouting conditions on properties of extrudate products produced on the basis of these differently sprouted samples and methods to evaluate the progress of the sprouting process exists. Therefore, this work aimed to get a deeper
more » ... o get a deeper insight into these issues. For this purpose, a simple and standardized system, the degree of sprouting method, was developed to characterize the sprouting progress by a visual inspection of the lengths of the coleoptile and radicles. Eight degrees of sprouting were defined. To test this method, wheat and oat grains were sprouted for different periods and at different temperatures. The grains were then processed by drying, milling, and extruding them using a twin‐screw extruder. The sprouted grains were assigned a degree of sprouting to determine the average degree of sprouting of all grains sprouted under the given conditions. The average degree of sprouting was subsequently correlated with the flour and extrudate properties. The presented study indicated that the degree of sprouting concept is a reliable method to predict product properties and is, therefore, of use for product development and specification. Furthermore, the results of the investigation of different sprouting times and temperatures on the properties of the resulting flours and extrudates provided new valuable insights. By sprouting the grains at 20 °C and/or for long sprouting periods of up to 9 days the most significant changes in the flour and extrudate properties were determined. Extrudates based on sprouted wheat were found to expand less, have bigger pores, a darker color, a softer structure, and were more water‐ soluble. These findings were attributed to the reduction in the starch content as the result of the enhanced enzyme activity during sprouting, t [...]
doi:10.14279/depositonce-11471 fatcat:cqcgrrpu35g5vg5pk2zmdihwx4