EFFECT OF MECHANICAL-STRESS AND REDUCING SUGAR CONTENT OF SEMOLINA ONPASTA DAMAGE DURING DRYING

Samples of pasta (spaghetti) with different semolina granularity were used to investigate the influence of mechanical stress on the Maillard Reaction in a pilot plant. Evolution of furosine content was used as an indicator of thermal stress and was related to the concentration of reducing sugars. During the VHT (very high temperature) drying cycle, furosine increased with the steepest gradient corresponding to the ma ximum temperature. Furthermore, as the granularity of the semolina dec reased, the pasta furosine content increased during drying. The mechan ical stress during the milling stage did not appear to make a consider able contribution to the formation of reducing sugars. Reducing sugars increased in the pre-pasting, pasting and extrusion/moulding phases. As is well known, amylolytic activity in creases with the increase in surface area associated with the various granularity values. In fact, the lower the granularity of the raw material the higher the increase in reducing sugars.