Ground Coffee Solutions: from Filter to Turkish coffee
IMA Coffee Petroncini offers an engineering perspective for a proper treatment of ground coffee
Coffee is the most popular beverage in the whole world, yet it is not consumed everywhere in the same way. Moving through the different regions of our planet, it is easy to see that almost every country or every region in the world has different approaches to coffee, and this is why coffee is called a “Glocal” beverage, globally consumed according to local traditions.
One of the biggest differences in how people drink coffee is the way they brew it. There are many brewing methods that can nonetheless be divided into three main styles: Filter brew, Espresso brew and Turkish style. Each one of these methods is strictly linked to grind tuning. It is understandable that one of the key factors affecting the “quality” of a coffee is closely linked to the consistency of the grind.
Consistency is the key
“One important way to control the consistency of the coffee is to maintain stability in the grinding process, guaranteeing the same particle size distributions in the ground coffee right throughout the year, despite environmental parameters” says Gian Pietro Balboni, Process Engineer at IMA Coffee Petroncini.
“To achieve this result we need to focus our production on two points: first, how to control the fine particles distribution of the ground coffee and second, keeping the temperature of the coffee under control” he adds.
“The principal grinding technology, and the most widespread on the market, are blade grinders, where the grinding process is performed by two circular blades with concentric crowns of teeth, each one corresponding to a grind step where you can regulate the output by adjusting the gap. This technology has the advantage of offering a flexible way to produce. One grinder can be installed for each type of coffee you want to make: one set for Espresso, one for Filter, one for Turkish etcetera.” Gian Pietro explains.
Roller style grinding is the second technology available in the Petroncini portfolio and is the grinding method that all major companies are using, becoming a key to their success. The ability of this technology to modify the fine grind and particle distribution is carried out through different stages of rolls.
“By controlling gaps and speeds, you can control the “scissor” effect in order to create more or less powder without shocking the coffee itself, since the crushing is performed not in one but in three different steps such as pre-crushing, grinding and fine grinding” Balboni says.
“The other important point is to keep the temperature stable during grinding. Only with good grinding technology can you make sure the temperature increase stays at a negligible percentage. Roller style grinding is linked with the centralisation of production in one single station to feed different downstream coffee formats” he explains.
Innovation in ground coffee processing
Compared to one decade ago, attention paid to coffee processing has increased exponentially, especially when it comes to ground coffee. Due to its specific characteristics, ground coffee is subject to chemical conditions that can dramatically affect the final quality and cancel the whole upstream process.
“Over the years, we have seen major changes in ground coffee processing. Coffee factories pay more attention to the quality of the final product, because it has to maintain the best quality in the cup. There are several treatments which, if not done properly, can compromise the consistency of the grind during the process.”
Degassing, handling, and homogenising, Balboni says, are the crucial points of ground coffee processing.
The flat extraction system designed by IMA Coffee Petroncini
Solutions for Turkish coffee: an in-depth focus
Ground coffee crusher
Powder homogenizer mixers for coffee and spices
Coffee and spices homogenizer
There are different extraction systems, but we have our own philosophy about this. Ground coffee must be properly homogenised and dosed, avoiding agglomeration in the bottom of the silo. So the extraction system plays an important role during the last part of this process. We have engineered ExtraMAX, equipment for ground coffee extraction, with a flat extraction system. While the circular extraction system is suitable for Turkish coffee, especially for production exceeding 900 kg/h, ExtraMAX has been designed for filter, Espresso and Moka coffee. Compared to other vibrating systems, the ExtraMAX system can effectively homogenise the product with accurate control of the dosage, which is impossible with vibrating devices.
Turkish coffee is a very particular product that requires some special treatments, yet it can bypass other ones that are strictly necessary for Espresso, such as degassing. To make Turkish coffee, each bean is evenly divided into 40,000 particles.
For large Turkish coffee productions in particular, it is important to use a water-cooling system applied to all rolls and the entire surface of the homogenizer, so that the coffee temperatures always remain below 40°C, avoiding any coffee oils and aroma losses. Homogenizing feed screws allow for perfect product mixing, avoiding agglomeration. It also means you can obtain the soft texture typical of Turkish coffee, without overheating it.
Even if we have done an ultrafine grind, a certain amount of chaff ends up in the ground coffee ready to be packed.
In the case of Turkish coffee, the ultrafine grind size means the coffee can be poured into boiling water. Removing the chaff for Turkish is a frequent request to avoid any disturb in the cup.
Many customers wanted to crush the chaff that ends up in the ground coffee, so, we have developed the T-Crusher, a ground coffee crusher capable of minimising the visibility of chaff in the coffee, thus uniforming the appearance of the ground coffee. This works by pressing the coffee in a certain area, where there are blades that work at high speed. In addition, for the most demanding customers, we provide a special vibrating sieve, able to completely remove any presence of chaff in the coffee, even the finest.
Powder homogenizer mixers for coffee and spices
Cardamom and other spices are used in Arab countries to add flavours to the coffee. Adding spices can be done just before serving the coffee or coffee and spice can be bought already mixed. Mixing coffee and spices in a Turkish coffee processing plant is a crucial operation, which can be done with the right dosage of the spices. Generally, the amount of spices per pack has a range of 3-9%, even if in some cases it could reach 20%.
Petroncini provides two systems for homogenizing coffee and spices, either continuously or by batch. The continuous powder homogenizer is suitable for mixing coffee and one selected spice, which can be changed according to the production. This system is called DuoMIX and it has been engineered by our team to guarantee process reliability and high productivity, from the mixing right up to very specific follow-up handling. The system works continuously and guarantees the consistency and repeatability of the mixing results by setting the percentage range of the desired spice.
The other solution, which is more precise even if less cost-efficient and time-consuming, due to the need to weigh the product batch by batch, can process an unlimited variety of spices that can be added to the coffee. This system operates through the action of weighing devices that put the precise amount of spices into the process before homogenisation.