A MODERN GAS COFFEE-ROASTING PLANT WITH A CAPACITY OF 1,000 BAGS A DAY
General view of the roasting room of the Jewel Tea Co., Hoboken, N.J. The equipment consists of twelve Jubilee gas machines in four groups; each group having a smoke-suction fan, and a drag conveyor over the three feed hoppers. To the left is a line of flexible-arm cooler cars.
For many years the regular factory machines have been of a size suitable for roasting two bags of coffee at a time; but roasters of larger size have recently come into considerable use.
Plants treating from fifty to a hundred and fifty bags per day are the most common; but the daily capacity runs up to a thousand bags or more. The minimum cost of equipping a plant is somewhere between five thousand dollars and ten thousand dollars. The individual machines are of standard construction; but the arrangement in a particular building, especially for the larger plants, is worked out with great care and with numerous special features, so that the goods can be handled from start to finish with minimum expense for floor space, labor, power, etc.
The practical coffee roaster locates his roasting room in the top floor of his factory building, where light and ventilation are generally best. He usually has a large skylight in the roof, directly over the roasting equipment. In addition to the advantage as regards good light and the convenient discharge of smoke, steam, and odors, through the roof, the top-story location makes it possible to send the roasted coffee by gravity through the various bins which may be needed in connection with subsequent operations, such as grinding, and for temporary storage before the final packaging and shipping.
Wholesale Coffee-Roasting Machinery
The indispensable coffee operations are roasting and cooling; and in practically all United States plants the cooling is followed by "stoning". This is an air-suction operation that effects, aided by gravity, the removal of any stones or other hard material that would damage the grinding mill. The best commercial cleaning and grading of the green coffee has usually left in every bag a few small stones. These can be got rid of better after the coffee is roasted; because it is then not only lighter, but more bulky.