The deduction of a kinetic model of colour formation, especially by the Maillard reaction, in heated concentrated carbohydrate solutions is described on the basis of systematic experimental studies. The main parameters of the colour formation are included such as reaction time, temperature, pH, amounts of sucrose, glucose, fructose, amino‐nitrogen and dry matter. The model is based on a three step first order consecutive reaction beginning with sucrose via glucose/fructose and dicarbonyl compounds to the colourants. The suitability of the model was tested on model experiments as well as on experiments with technical solutions in an evaporation station. It resulted in a good correspondence between measured and calculated colour values. The potentials of the model are discussed and the range of applications is pointed out.

of the starting materials and the catalyst. A quantitative correlation for the influence of the concentrations is given. Furthermore, the influence of mass transfer processes was considered. Under unfavorable conditions gas liquid mass transfer can be rate-limiting.

The cyanohydrine of 3‐ketosucrose can be obtained in good yields and with high regioselectivity. The stereoselectivity is 90 % for the isomer with axial orientation of the cyano group. By this reaction route a sucrose derivative with CC bonding of the substituent can be obtained in two steps without protecting groups in aqueous media. By its hydrolysis 3‐cyanoglucose is accessible.

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