Clarified juice is concentarted in evaporators, normally with five bodies (Figure 26). Concentration increases from 15º brix until approximately 65º brix.
Figure: Evaporator system with five effects
Colour can be formed during evaporation. Non enzymatic oxidation reaction of phenolic can occur. However the velocity of this reaction is lower as the one of enzymatic browning reactions (Paton, 1992).
After evaporation, sugar syrups and masses have higher concentrations, as in the previous factory sections. From 15º brix sugar products pass to values between 70º brix and 80º brix, in syrups out of centrifuges and higher than 90º brix in massecuites from vacuum pans. At these concentrations , Maillard reactions can odccur, with formation of melanoidins. The formation of these compounds depends mainly from amino compounds concentration and from other factors as pH, brix and invert sugars concentration (Paton e McCowage, 1987).
Paton N.H., 1992, The origin of colour in raw sugar, Proc. of Aust. S.S.C.T. Conf. 8-17
Paton N.H., Mc Cowage, 1987, Colour forming mechanisms during mill processing, Proc. of Aust. S.S.C.T.