In 1891, the New England Automatic Weighing Machine Company, Boston, Mass. began the manufacture of machines to weigh coffee into cartons and other packages; and in 1894, installed in the Chase & Sanborn plant at Boston the first automatic weighing machine in the coffee trade. The New England concern was subsequently (1901) succeeded by the Automatic Weighing Machine Company of Newark, N.J.
In 1893, the first direct-flame gas coffee roaster in America (Tupholme's English machine) was installed by F.T. Holmes at the plant of the Potter-Parlin Company, New York.
In 1893, Cirilo Mingo, of New Orleans, was granted a United States patent on a method of aging green coffee to give it the characteristics of green coffee stored in a confined space for a long period. The operation consisted in placing layers of green coffee between dry and wet empty coffee bags, and permitting the beans to absorb eight to ten percent of the moisture in a period extending from six to sixteen hours. This was one of the earliest efforts to mature and age green coffee in the United States.
In 1894, the business of the Pneumatic Scale Corporation, Norfolk Downs, Mass., had its start in Quincy, Mass. where the first pneumatic weighing machine was installed by the Purity Dried Fruits Cleansing Company. In 1895, the Electric Scale Company was organized to build the machines, the subsequent development of this line of packaging machinery for coffee being directed by the Pneumatic Scale Corporation, Ltd., which succeeded it.
In 1895, Adolph Kraut introduced the German-made grease-proof lined paper bags for coffee to the American coffee trade. That same year, Thomas M. Royal, of Philadelphia, began the manufacture in the United States of a fancy duplex-lined paper bag for coffee.
In 1896, natural gas was first used in the United States as a fuel for roasting coffee.
In 1897, Joseph Lambert, Vermont, first introduced to the coffee trade a self-contained coffee roasting outfit without the brick setting required until then.
In 1897, the Enterprise Manufacturing Company of Pennsylvania was the first regularly to employ an electric motor to drive a coffee mill.
The overproduction of coffee began to be so serious a question by 1898, that J.D. Olavarria, a distinguished Venzuelan, proposed a plan for the restriction of coffee cultivation and the regulation of coffee exports from countries suffering from overproduction. In this same year, the bears forced Rio 7's down to four and one-half cents on the New York Coffee Exchange.
In 1898, Edward Norton, of New York, was granted a United States patent on a vacuum process for canning foods, subsequently applied to coffee. Others followed. Hills Brothers, of San Francisco, were the first to pack coffee in a vacuum, under the Norton patents, in 1900. M.J. Brandenstein & Company, of San Francisco, began to pack coffee in vacuum cans in 1914. Vacuum sealing machines to pack coffee under the Norton patents are now made by the Perfect Vacuum Canning Company of New York.