Beverage processing: grinding coffee

Almost all coffees sold are ground industrially by metallic micrometric grinding cylinders assembled in pairs.

Beans must be hard brittle and cold. Grinding is easier when the roasting process was intense. Light roasting yields beans that are soft and tend to be flattened during grinding rather than being reduced to powder.

During grinding, carbon dioxide contained in the coffee bean escapes – this is the degassing of the bean.

The extent of grinding determines in part organoleptic qualities in the coffee.

When the grind is too fine, the procedure for preparing the beverage is long; the water has time to cool so that it draws down particles that sink to the bottom of the cup. The coffee is then muddy and acrid.

When the grind is too coarse, the water filters through too quickly and the coffee’s savor is bland.

During filtration, the optimal rate of extraction is 18 to 22% of the weight of the ground. Ground coffee must be wrapped quickly n order to avoid oxidation and loss of aroma. It is vacuum packed less than eight hours after grinding.
Beverage processing: grinding coffee

Coffee Consumption in History

Coffee Consumption in History
It seems that coffee was brought from Ethiopia to the Middle East around the year 575, and was cultivated in Yemen near the port of Mocha. Starting in the 8th century, the Arabs prepared coffee as an infusion, and the practice of drying and roasting the grains began only in the 14th century. In the 15th century, coffee consumption was introduced into Aden by Mufti Gemaleddin Abou Abdallah who during his trip to Persia heard about the wonderful effects of an infusion. His strength was restored and he reported that it “made him light-headed, brightened his spirits, and delayed the onset of sleep”.

The habit of drinking coffee spread form Aden to Mecca, Medina, Cairo and Alexandria, to Persia as well as Aleppo, Damascus, and Istanbul. Arab armies introduced the habit of drinking coffee into all the countries that they conquered: the Balkans, Spain and North Africa.

Up until the 16th century, the Arabs tried so hard to maintain their monopoly of coffee production that travelers from other countries never even mentioned coffee in the accounts of their trips. The crusaders made no mention of coffee upon their return to the western world.
In 1555, Schems and Hekem, Syrians coming from Damascus and Aleppo, opened the first two public cafes in Istanbul. Their client – pots, scholars, gamblers – ensured their success in such a sort times that Turks merchants quickly opened up several other shops.

However, it was impossible for Arabs to maintain absolute control over the comings and goings of great numbers of travelers, especially during pilgrimage to the Mecca. One of the pilgrims from India succeeded in bringing back to Mysore seeds from the coffee tree. He planted them in front of his hut in the mountains of Mysore in India. From here the seeds were the source of all of the coffee trees in this region.
Coffee Consumption in History