The Elektra Micro Casa a Leva home espresso blog

The Elektra Micro Casa a leva is a beautiful home espresso machine. But is it capable of making great coffee? Follow my pursuit of ultimate espresso coffee as I learn to use this exciting machine.

Location: Trondheim, Norway

Sunday, June 19

How the lever machine was invented

A couple of days ago I received a postal parcel containing two books by Kenneth Davids (ordered from Kenneth Davids has written several books about coffee. I already had his book about home coffee roasting, which I would say is excellent reading. Now I also have ”Espresso –ultimate coffee” and ”Coffee –A guide to buying, brewing and enjoying”. I think his books are inspiring ☺

The historical parts of ”Espresso –ultimate coffee” are informative reading. I will retell what he says about the development of espresso machines. Kenneth Davids starts by giving the background for the events leading to the invention of espresso as a brewing method.

Coffee came to Europe in commercial quantities through the port of Venezia (Venedig) in the seventeenth century. The first European coffeehouses started in Venezia, and they most certainly served strong, heavy-bodied coffee, prepared Turkish-style in an ibrik. So this taste for strong coffee, made from finely ground, dark-roasted beans, came as a result of influence from arabic coffee culture. Later, in the eighteenth and the nineteenth century, influence from Austria also became evident. The Austrians had developed a taste for filtered coffee, often served with milk.

My own ibrik

So it is filtered coffee, combined with a taste for strong, darkly roasted coffee, brewed by the cup, on demand, that is the very idea behind the development of espresso. The rest of the story is about improving technology.

The filter pot that existed was a slow brewing method, especially if the coffee was ground too fine. Using only gravity to pull water through the ground coffee wasn´t satisfactory, especially in a commercial environment.

Many inventions throughout the nineteenth century focused either on vacuum or steam pressure to force water through coffee. The well-known mocca pot, among others, was invented. The first commercial machine, made in 1855 for the Paris Exposition by E.L. de Santais, used steam pressure to raise water to a considerable height. The weight of the water applied the brewing pressure. This machine could prepare coffee at high speed.

Luigi Bezzera, from Milan, should be credited for coming up with the idea (in 1901) of machines having “brewing groups”, where coffee was brewed directly into the cup. This machine configuration stays the same today.

The need for improving speed of preparation by applying force seems to have been just as much of a driving force behind espresso technology, as the idea that pressurizing coffee might extract more flavor compounds (that is a surprise to me).

But none of the earlier method of applying pressure could break the 1 ½ atmosphere ceiling. Some of the inventions (1920s and 1930s) that could break this barrier used the pressure of tap water, which was heated with electric elements before reaching each brewing group. In 1938, Francesco Illy, built a large machine, “Iletta”, that used compressed air to raise the pressure.

But the great breakthrough of technology came when Signor Cremonesi before World War II patented a piston, which, when a horizontal lever was turned, was forced downwards in a screwing motion. Another Milanese, Achille Gaggia, was experimenting with similar technology at the same time. The war made experiments stop, but in 1947, Gaggia came up with the “lever group”, where a powerful spring was compressed by pulling a long lever. When the spring expanded, a piston forced hot water through the coffee at a high pressure. In 1948, the first machines were produced. Espresso in its modern form, rich in taste and topped with a layer of insoluble substances, became the new standard.

All espresso machines since then, and the introduction of pumps and better temperature control, are really only refinements of Achille Gaggia´s patent of 1947 (as most people know, Gaggia is a well known italian brand, and their newest lever machine, is actually named "achille"). Because this blog is about a lever machine I will end this fascinating story here…


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