Fig. 47.
The mass is taken out of the machine in lumps, and in order that it may be reduced to a temperature suitable for the removal of air (about 26-32 ° C. on the outside) it is laid to cool on wooden, marble or iron tables. When this temperature is arrived at, large lumps of chocolate are introduced either into the air-extracting or the dividing machines.
Fig. 48.
After the importance of the tempering processes had at length been recognised, inasmuch as the maintenance of the temperature prescribed is of immense influence on the chocolate subsequently produced, and it had on the other hand been ascertained that such machines as described above could not be absolutely relied upon, for the shaking tables involve an occasional excess of tempering, the idea of a machine which should completely and automatically perform this task was finally conceived. This new machine, given in fig. 48, and already differing from all other tempering machines in external appearance, ushers in an entirely fresh process respecting the modus operandi prevailing in the present manufacture of chocolate, which does not fail to satisfy the highest expectations. It may be said to work continuously, for no matter what the temperature of chocolate passing into it may be, the material leaves the machine at the temperature desired within a lapse of one minute. According as more or less chocolate has to be turned over in the moulding department, the machine can be stopped or set in motion without detriment to its efficacy. Besides this, it cleans almost automatically, so that a quick change of quality is always possible. The special virtue of this machine is that it turns out the material with such a degree of homogeneity as has never before been known, making moulding at much higher temperatures a possibility. There is yet another side issue, namely a doubling of the life of the moulds, and finally, owing to the fact that the often considerable amount of waste material is done away with in this process, the moulding shop is spared to some extent. The series of rollers through which the chocolate passes is maintained at a proper temperature by means of automatic water apparatus. The daily output of the machine figures at 3000-4000 kilograms. The material is passed on out of this machine to the dividing and moulding processes.
The necessary extraction of air follows immediately on the tempering process, for the blades of the scraper then release the chocolate mass from the rollers in thin layers, between which air penetrates. The removal of air is effected by machines, an old type of which is shown in fig. 49 (in front elevation).
It can be warmed by means of a charcoal fire placed in the space i, or by any other suitable means. The chocolate mass is fed into the cylindrical hopper a, at the base of which occurs an archimedian screw b, which is propelled by the shaft and cog-wheel system c d e in the direction indicated by the arrow. Thus the chocolate mass is forced into the box f, leaving which in cylindrical form, it succeeds to the travelling band h. It is now almost entirely freed from air. As the material is pushed forward on the band, it is cut off either by a knife g fixed to the box f, or divided as far as possible into equal parts by a double knife with adjustable blades corresponding to the weight required for a chocolate square. This manipulation presupposes a fair amount of skill on the part of the machinist, but this once attained, the division ensues as precisely and simply as can be desired.
Air-extracting machines of recent construction, although still partially built on the above principle, are at the same time generally developed as automatic dividing machines.
Fig. 49.