[翻译]espresso machine 意大利浓缩咖啡机

由 fatdragoncat 于 周四, 2007-06-21 15:44 提交翻译。

只有一种方法能制造出如此浓郁芳香的咖啡，“真正的意式espresso”是借助机器，产生高压的水流，冲过咖啡而成。掌握好温度与压力之间的平衡度，是淬取出咖啡粉中的蛋白质、糖份、油脂到espresso中的关键。

从1903年到50年代初期，有许多的专利出现，也有许多品牌获得了成功，比如Cimbali, San Macro, Marzocco ,Gaggia 和 Faema等。几乎所有的咖啡机都是由锅炉系统、控制系统、压力泵系统和分配系统组成。

锅炉系统是一个煤气或者电加热的锅炉，它负责为整个机器提供热水和蒸汽，热水经过控制系统、压力泵和分配系统将高压热水传送到滤器，令到热水在9bar的压力下冲过滤器里的咖啡粉。

控制系统
早期的机器，是直接利用锅炉内蒸汽压力把热水传送到分配系统，这种情况对于操作者来说，是非常难控制的，因为必须完美地协调蒸汽和热水的温度，防止过度的热量催毁咖啡当中的芳香物质。

后来，水温被固定为90度，而压力 也不再直接来源锅炉内的蒸汽，而是改用活塞进行传递，活塞在控制杆的操控下释放压力。

压力泵系统
控制杆在操作的时候，偶尔出因为脱手等原因造成意外，于是又出现了改良的型号，活塞的压力来源改由顶部的冷水提供，这个系统有两个活塞，压力来源于两个不同的液面，从而保证产生比较恒定的9bar的压力。

分配系统
分配系统的诞生为espresso机带来了一场全新的革命，在它发明以前，是直接利用锅炉里的热水冲煮espresso，分配系统引入了热交换的概念，锅炉内有一根圆柱型 的管子，水在9bar的压力下传输过管子，达到合适的温度。

The Espresso Machine

The only way to make that thick，creamy and fragrant．”real Italian espresso”iS to use machines that force hot water through the ground coffee at high pressure．
The right balance between temperature and pressure iS the key to correct extraction of the proteins，sugars．oils and colloids contained in the ground coffee and for transferring them to the espresso．Since 1903(when Mr．Bezzera patented the first machine for making Italian coffee) to the early ‘fifties there has been a rapid succession of new patent and trademark registrations．
Pavoni and Vittoria Arduino in 1 905 were followed by Cimbali，San Marco，Marzocco，Gaggia and Faema．Nearly all consist of a boiler where the water iS heated by a gas burner or electric heating element；another unit iS connected to the boiler．It may a lever, hydraulic, distribution type and it pushes the hot water through the coffee in the filter baskel at a pressure of 9 atmospheres．

Lever Unit

The early machines moved the hot water through the thrust of the steam directly from the boiler to the distributing unit．This was complicated procedure because the operator had to create a perfect balance between steam and water to prevent the coffee from being ”attacked”by too much heat that would have ruined the aroma．

Subsequently，water temperature was set at 90。C and the desired pressure was obtained not directly from the steam，but mechanically．with a piston． The piston，pushed by a spring pressed the amount needed to make the espresso through the coffee in the filter basket．

Hydraulic Unit

Since the lever that loaded the spring could occasionally slip out of the operator’s grasp and cause accidents，an improvement was made． Pressure on the piston was produced by cold water on the top part：this was the birth of the ”hydraulic”or “hydraulic mechanical”unit that makes it possible to attain a Pressure of 9 atmospheres using two pistons with different surface areaS．

The top piston receiving the pressure from the cold water in the pipe has a larger diameter and it pushes down on the smaller，lower piston．The final pressure is directly proportional to the difference between the surface area of the two pistons and the pressure in the system．

Distribution Unit

The distribution unit created a revolution in the world of espresso machines．Until it was invented，it was hot water from the boiler that made the espresso．with a11 the problems related to its use．The distribution unit introduced the heat exchanger concept．A cylindrical pipe inside the boiler carries the water pushed at a pressure ot 9 atmospheres vive that goes into action when the esPresso 1s being made． There is one important note to all this．however．If on the one nand new technologies have improved and simplified the operator’s work in making espresso，on the other hand。 and precisely because the task is purely manual and very simple (there are machines that automatically grind， measure，adjust pressure，emulsity clean filters．etc．)there is often a lack of professionalism among operators who now iust have to push a button (just watch an ”espresso”being made in the many service areas along the highways)．