In previously describing the aleuron granules of the cacao bean it was mentioned that they contain a comparatively large globoid. According to Molisch[85], when sections are cautiously heated on platinum foil, these globules are found in the ash. From their number they give a characteristic appearance to the ash of cacao beans, and thus may serve as a good means of identifying cacao, since they can be detected in the smallest quantity of a genuine cacao preparation.
A noteworthy fact may here be mentioned, namely the presence of a rather small amount of copper in the ash of cacao beans as well as the husks. Duclaux[86] was the first to point out this fact, which several other observers, such as Skalweit[87] and Galippe[88] have also confirmed. The amount of copper in the husk varies from 0·02 to 0·025 percent and in the beans from 0·0009-0·004 percent (Duclaux). Copper in similar amount is found in all kinds of beans and husks, and its presence is due to the absorption of copper by the plant from the soil, whence it gradually accumulates in the fruit.
Most of the constituents which exist in the cacao kernels are also to be found in the husks and the methods for isolating and determining them are the same in both cases. The composition of the husk, according to Laube and Aldendorff[89], is as follows:
Key to Row 1: Col 4A = Nitrogenous substance Col 6B = Non nitrogenous extractive ———————————————+——————+—————+————-+————-+————-+————-+————-+————— |Amount| | | | | | | | of | | | | |Woody| | |husk |Water| 4A | Fat | 6B |fibre| Ash | Sand ———————————————+——————+—————+————-+————-+————-+————-+————-+————— | ~Per cent~ ———————————————+——————+—————+————-+————-+————-+————-+————-+————— Caracas | 20·09| 7·74|11·68| 5·99|35·29|12·79| 8·32|18·62 Guayaquil | — | 9·11|12·94|10·75|47·08|13·12| 6·79| 0·21 Trinidad | 14·04| 8·30|15·14| 4·23|46·05|18·00| 7·06| 0·92 Puerto Cabello | 14·92| 6·40|13·75| 4·38|47·12|14·83| 6·06| 7·46 Soconusco | 18·58| 6·48|19·12| 6·48|39·39|15·67| 8·15| 4·71 Mean | 16·33| 7·83|14·29| 6·38|45·79|14·69| 7·12| 5·90
~Zipperer’s analysis[90] of the unroasted husks gave the following results~:
Key to Row 1 abbreviations: Col 2 = Surinam = Surin Col 3 = Caracas = Carac Col 4 = Trinidad = Trini Col 5 = Puerto Cabello = P Cab Col 6 = Machala = Mach Col 7 = Port au Prince = P a P