A brief review of sugar crystallization governed for quite a long time by the "artisan pan man" is followed by expressing the need for change in instrumentation and control practice. Common myths like the "master boiling", measuring viscosity/consistency, density or solids content (brix) and using these data as supersaturation, and the common belief that supersaturation is not that important after seeding has been completed are strongly refuted. Paying due attention to its importance, supersaturation is introduced as a multivariable function of several variables. Its role in determining crystal quality and crystal growth are discussed in more detail. Crystal quality, the amount of fines and conglomerates and the rate of production depend very much on supersaturation, all of which have a profound effect on the cost of production. Different methods of seeding are discussed and it is argued that full seeding implemented by using seed magma is the preferable way to do it. The mass production of sugar requires new skills to do it right: on-line measurement of meaningful data and their use in advanced automatic process control have brought change in a rather conservative industry, where old habits die hard. The role of the local laboratory, unable to meet quite a few of these requirements has diminished. Problems with high feed syrup concentration, massecuite circulation and pan design (feed syrup entry, sensor location selection), crystal size distribution and the methods of basic strike control are briefly discussed.
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