4. ~Estimation of alkalis remaining in cocoa powders.~ The ash obtained from 5 grammes of cocoa powder is washed out of the platinum pan into an ordinary water glass or tumbler, distilled water only being used for this purpose, afterwards finely crushed with a glass rod and heated to boiling point. The liquid is then allowed to settle, filtered and re-washed. At this stage 5 cubic centimetres of n/1 sulphurous acid are added, the liquid again heated to boiling point and titrated with 2/n or n/4 alkaline lye. In this way the quantity of added carbonic mineral matter is determined, in addition to the amount of carbonate present in ordinary cocoa powders, which is formed from the organic acid minerals when the ash is produced. Welmans has determined these values in the commonest varieties of beans and placed the results obtained at our disposal for the second edition of this book. These results are as follows: a) Unshelled roasted beans ===================+========+=========+=========+=========+ | Ariba | Ariba | Caracas | Caracas | Per cent. | I | II | I | II | ===================+========+=========+=========+=========+ Ash | 4·198 | 4·02 | 7·52 | 4·376 | Soluble in water | 1·698 | 1·66 | 1·34 | 1·676 | Insoluble in water | 2·5 | 2·36 | 6·18 | 2·70 | Alkali (considered | | | | | as potash) | 0·6417 | 0·6417 | 0·596 | 0·9936 | ===================+===========+==========+======= | Guayaquil | Trinidad | St. Per cent. | | | Thomé ===================+===========+==========+======= Ash | 5·12 | 3·6 | 3·92 Soluble in water | 2·11 | 1·565 | 1·604 Insoluble in water | 3·01 | 2·035 | 2·32 Alkali (considered | | | as potash) | 0·84 | 1·125 | 0·67 b) Shelled, roasted beans: