ICYTAC   23898
INSTITUTO DE CIENCIA Y TECNOLOGIA DE ALIMENTOS CORDOBA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Effect of ball milling on thermal and morphological properties of sorghum flour.
Autor/es:
PALAVECINO, PABLO MARTÍN; PENCI, MARÍA CECILIA; GONZÁLEZ, LUCIANA CARLA; RIBOTTA, PABLO DANIEL; TOLABA, MARCELA PATRICIA
Lugar:
Stuttgart
Reunión:
Conferencia; 5th International ISEKI_Food Conference; 2018
Institución organizadora:
ISEKI_Food
Resumen:
Sorghum is a cereal crop underutilized in human diet of western countries despite its potential health benefits and its agronomics advantages. In the past few years, there have been a growing interest on the physical methods to enhance the functional properties of flours where we can highlight planetary ball milling. This technology is able to improve the material characteristics without the production of hazardous materials. Then, the aim of the present work was to evaluate the effects of ball milling on sorghum flour thermal and morphological properties in order to broaden the applications of this cereal. Partially decorticated white sorghum flour (76.0% db total starch) was grinded using a planetary ball mill (PM-100, Retsch, Germany) and milling energy was set in five levels (0.26, 0.99, 1.96, 2.93 and 5.84 kJ/g of sample). Median particle size (D50) decreased from 57.2 µm to 20.8 µm with increasing energy, but span (particle size dispersion) remains practically constant. The parameters of the fitted comminution law indicate that a fraction of the applied energy was used to generates new surfaces. The deterioration of starch granules observed by SEM was reflected in an increase in the flour damaged starch content, reaching values of 17.9% and regarding RVA parameters, only final viscosity and consequently setback pasting parameters exhibited significantly differences among samples. Gelatinization temperatures were not significantly affected by ball milling, however the gelatinization enthalpy (∆H) decrease with the increase in grinding energy, in agreement with crystallinity loss during ball milling process, with CD decreasing from 28.8% to 17.0%. Planetary ball milling significantly affects sorghum flour thermal and morphological properties due to the destruction of the starch granule structure. This demonstrates that this method is suitable for the production of modified flours without the use of chemicals and water.