CHARACTERISATION OF CASSAVA BAGASSE IN DIFFERENT GRANULOMETRIES FROM TWO STARCH PROCESSING PLANTS

摘要

Cassava is an agricultural crop that occupies an important place in the diet of people of many countries in tropical and sub-tropical regions. Cassava bagasse is a by-product from industrial processing that is generated in great quantities and it can exhibit about 40-50 % of starch in its composition, in dry basis. Two samples, one moist (sample A) and another dry (sample B), were supplied by two cassava starch industries. The samples were analysed by physicochemical, thermoanalytical (TG, DTA, DSC), rheological (RVA) and micro-structural methods (NC-AFM) that demonstrated that the temperature of the industrial drying (around 150 oC) was not very well controlled, reaching higher temperatures, reaching decomposition of organic matter condition causing changes (please specify) and browning. Although it was milled, sieved and contained 41.31 (?0.43) % of starch, sample B did not present gelatinisation or paste properties. Sample A, with 47.75 (?0.21) % of starch, dried carefully in a laboratory oven with forced air circulation at 45 oC for 24 hours showed gelatinisation enthalpy (?Hgel) and viscosity with values directly proportional to the granulometry.