ROASTIira THE BEAN. 39 



'^The Ijerries of coffee once roasted lose every hour somewlaat 

 of their aroma, in consequence of the influence of the oxygen of 

 the air, which, owing to the porosity of the roasted berries, can 

 easily penetrate. This pernicious change may best be avoided by 

 strewing over the berries when the roasting is completed, and 

 while the vessel in which it has been done is still hot, some 

 powdered white or brown sugar (half-an-ounce to one pound of 

 coffee is sufficient). The sugar melts immediately, and by well 

 shaking or turning the roaster quickly, it spreads over all the 

 berries, and gives each one a fine glaze, impervious to the atmos- 

 phere. They have then a shining appearance, as though covered 

 with a varnish, and they in consequence lose their smell entirely, 

 which, however, returns in a high degree as soon as they are 

 ground. After this operation they are to be shaken out rapidly 

 from the roaster and spread on a cold plate of iron, so that they 

 may cool as soon as possible. If the hot berries are allowed to 

 remain heaped together, they begin to sweat, and when the quan- 

 tity is large, the heating process, by the influence of air, increases 

 to such a degree that at last they take fire spontaneously. The 

 roasted and glazed berries should be kept in a dry place, because 

 the covering of sugar attracts moisture. 



" If the raw berries are boiled in water, from twenty-three to 

 twenty-four per cent, of soluble matter is extracted. On being 

 roasted till they assume a pale chestnut color, they lose from 

 fifteen to sixteen per cent., and the extract obtained from these by 

 means of boiling water is twenty to twenty-one per cent, of the 

 weight of the unroasted berries. The loss in weight of the ex- 

 tract is much larger when the roasting process is carried on till 

 the color of the berries is dark brown or black. At the same 

 time that the berries lose in weight by roasting, they gain in 

 volume by swelling ; one hundred volumes of green berries give, 

 after roasting, a volume of one hundred and fifty to one hundred 

 and sixty ; or two pint measures of unroasted berries give three 

 pints when roasted." 



