Hard Caramel Bonbons

Xylose is obtained by hydrolysis of hemicellu-loses. Catalytic hydrogenation of xylose yields xylitol. Xylitol is as sweet as sucrose. Due to its high heat of solution of — 23.27 kJ/mol (sucrose 6.21 kJ/mol), it produces a cooling effect in the mouth when it dissolves. This effect is utilized in some candies. 

Mannitol can be made by the hydrogenation of invert sugar. As a result of its lower solubility, it is separated from sorbitol, which is also produced in the process, by chromatography. 

For the production of these candies, a sucrose solution is mixed with starch syrup and boiled down to the desired water content either batch-wise or continuously (Fig. 19.10). Generally used are vacuum pans (120—160°C) and film boiling machines in which evaporation ttikes place in a rotating cylinder (110°C 142 °C, 5 s). Volatile labile components (aroma substances) are added after cooling. This apphes to acids as well in order to prevent inversion. Air is incorporated into the mass, if necessary. Subsequently, the mass is formed into a cord and processed into bonbons with the help of stamping or casting machines that require a shghtly thinner mass. Modem plants have a capacity of 0.6-1.5t/h. 

Component Hard caramel Soft caramel Fondant Marzipan filler Marzipan 

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