The principle of PHYSIS
Caramelization is a phenomenon that occurs in the sugar structure of materials that are heat treated, producing a dark coloration of the material. It occurs to the sugars of ketones and glucose present in the raw materials. It occurs at high temperatures, releasing pigments and the smell of rotten fruit. Furthermore, the sugars form a hard crust on the external surface of the granule, resulting in the trapping of water inside. In rotary dryers, the flame is introduced right at the entrance of the material, thus creating a thermal shock in the pomace, causing the effect on the external layer of the granule. To force the water trapped in the heart of the granule to come out, increasingly larger quantities of heat are required, causing an infinite cycle that aggravates the phenomenon. Furthermore, in dryers, steam continually advances with the material, which, being hot, reabsorbs the humidity of the environment. These aggravating parameters have the consequences of insufficient drying, odors and a dark coloration of the biomass.
