Memoir upon Coffce. 21 
The interval between roasted coffee becoming higher co- 
loured and its being charred, is so Jong, that it is extremely 
difficult to determine the point when it is necessary to stop, 
in order to preserve the agreeable properties of the beans ; 
but, in order to approximate to this point, so important to 
ascertain, I reckoned thrée distinct epochs in the roasting: 
ist, The bean loses its natural colour and passes to that of 
bread-raspings or dry almonds: 2d, The coffee becomes of 
the brownish red colour of Indian chestnuts: 34, Although 
almost black, it is not, however, charred. 
I took six ounces of Martinique coffee and divided them 
into three parts, which I roasted separately, and each of 
them to one of the above three degrees. 
The two ounces, lightly roasted, of the colour of dry al- 
monds, lost two drachms in the fire; this I shall call the 
first degree. 
The two-ounces roasted of’ the chestnut colour lost three 
drachms: this was my second degree. 
The two ounces roasted black lost three drachms forty- 
._ eight grains: third degree. 
No. 1. passed through the mill with difficulty *. A cold 
infusion of it contained tannin, and precipitated the solu- 
tion of gelatine. _ Its taste was strongly aromatic ¢; its fla- 
vour was that of almonds; it had no bitterness, and had a 
decisive green colour. A warm infusion had the same aro- 
* M. Cadet de Vaux, my uncle, has remarked, that to grind roasted coffee 
is not the best method, by bruising it ina mortar much more of the aroma is 
preserved. ¢ 
+ The desire of retaining the aroma which is dissipated at too strong heat 
has suggested two processes, not akogether useless; the one is in use in India 
and France, and consists in putting a little fresh beer upon the cotfee when it 
begins to colour in roasting in the cylinder: as much beer must only be used 
as will slightly varnish the surface of the grains. The beer retains a part of 
the essential oil which would have been evaporated. This is not a bad me- 
thod, but it sometimes gives the coffee a flavour which does not suit every 
one’s palate. ‘lhe other process consists in spreading the roasted coffee while 
hot and exuding, upon white paper, and then strewing it lightly over with 
sugar: the sugar absorbs the oil of the coffee and retains the aroma. This 
method, in my opinion, does not add to the agreeable qualities of the coffee, 
and makes one uncertain what quantity of sugar to put into a cup of coffee. 
B3 matic 
