Effetto del trattamento di soffiatura sulle caratteristiche fisiche di alcuni cereali

Puffed cereals are commonly used as breakfast cereals or as ingredients of sweet goods for their lightness and crispness. These properties are strongly related to their structure. Very little work has been reported so far about the physical modifications that take place during puffing. The aim of this research was to study the structural changes induced by puffing of three cereals (wheat, rice and rye) and of one pseudocereal (buckwheat) and to evaluate their physical properties. Puffing determined a different expansion according to morphological structure of the original grain. SEM micrographs of rice and rye transverse cross-sections revealed a highly porous structure with irregular void spaces having variable size and random locations. Puffed rice, on the contrary, presented a closely packed structure. The microstructure of puffed buckwheat revealed the formation of a large number of small pores. The different microstructure of puffed grains affected their apparent solid density and water adsorption index that appeared higher for buckwheat