The order of the above processes is subject under certain conditions to various modifications arising from the fact that the alkalis are applied at various stages in the course of manufacture, i. e.:
- I. before roasting;
- II. during roasting;
- III. after roasting,
and further
- a) before pressing;
- b) after pressing (treatment of the defatted beans).
The cleaning and sorting of the raw beans, or, in short, the complete treatment to which the raw cacao is subjected (a to c) is in all methods effected by the same machines, a description of which has been given on pages [Transcriber’s Note: Rest of line missing]
Some manufacturers proceed at once to treat the cacao with alkali on completion of the above operations.
C. Stähle[122] effects the disintegration of cacao by subjecting the beans to the chemical action of a mixture of ammonia and steam, at a temperature not exceeding 100 Deg. C. The next process (roasting) is then supposed to draw out the ammonia introduced into the material, which, being volatile, easily escapes, and enables the flavour to develop.
Pieper[123] moistens the raw beans with water, to which alkali has been added, and this has the effect of neutralising the acids present in the bean; afterwards the beans are fermented, dried and roasted. The fermentation is described as rendering the particles of albumin or protein bodies easily digestible and further imparts to the beans a fine, reddish brown colour. This process is therefore nothing but an after-fermentation of the cacao under the influence of alkalis. From a scientific point of view, the process does not possess the advantages which Pieper claims for it, with the exception of the really evident improvement in colour. This effect can, however, be obtained equally well by suitable treatment with water alone.
G. Wendt[124] has patented a method of improving the colour and facilitating the disintegration of cacao, in which the beans are treated, before roasting, with lime water and milk of lime (lime solutions) and further washed with the solution during roasting.
We now turn to the methods of disintegration by means of fixed alkalis (carbonate of magnesia, potash and sodium) first employed by the Dutch, concerning which the following description will be useful.