Neapolitan coffee maker. Kvant

On the pages of my blog, I talked about some types of coffee equipment, in particular, about a coffee maker. Today I want to share with you information about making Neapolitan coffee, or rather, tell you about the device for making it. Coffee makers of this type are practically not found in Russia.

Special coffee maker for making Neapolitan coffee

This cooking recipe was born in Italy, where they first began to cook and, but in its final form was formed in France, where the drink obtained with its help is called filtered.

Indeed, in a specially designed device, boiling water is supplied to the strainer, where ground coffee, passes through it and the finished solution enters the receiving vessel.

This method is the best suited for brewing a small amount of drink. Neapolitan coffee makers are not very common, although their good models, especially those made of stainless steel, are durable, strong and very convenient if you need to make two or three cups of coffee.

By purchasing such a device, you can use it for the rest of your life. The only weak point in its design is the insufficiently strong handle, which is the one that breaks in the first place.

In order to make good coffee, you need to choose the right grind. There are holes in the upper and lower compartments of the coffee maker, the sizes of which differ depending on the manufacturer. Therefore, it is best if medium to fine. By purchasing a ready-made ground mixture, you can pay attention to its universal varieties.

Determine what the water has reached desired temperature heating is not always easy. Sometimes a cylinder intended for water is preheated without removing the filters and receiving vessel until the boiling water is ready. If the appliance has been disassembled and the water has already boiled, extreme care must be taken to avoid scalding. On such models, non-heating plastic handles are installed. Sometimes, during the preparation of Neapolitan coffee, boiling water may come out on the lid or in another part of the appliance. Usually, it sinks down, flowing through the filter and the ground coffee compartment into the lower vessel.

After preparing and serving coffee, the appliance should be cooled down and only then disassembled for washing and cleaning. Usually both parts of the device are very carefully fitted to each other. With prolonged cooling, the metal parts of the device shrink, and it becomes more difficult to disassemble it.

How to Make Neapolitan Coffee in 5 Steps

1. During the first use of the device measure the capacity of the receiving compartment of the coffee maker. To prepare a drink, pour boiling water into the top of the appliance, then put the ground coffee in the compartment provided for this purpose and make sure that the granules do not fall into the holes. If the powder particles end up in the receiving vessel, then the coffee is too finely ground. Be especially careful if you are preparing just one or two cups of coffee: too thin a layer of ground coffee quickly passes boiling water, instead of holding it long enough for extraction.
2. Place the basket of ground coffee on the vessel with cold water and attach the empty receiving part of the appliance, holding it upside down. The ways of connecting the individual parts may be different, but in any case they must be safe.
3. Put the appliance on low or medium heat in the still upside down position and wait for the water to boil. Sometimes this moment is difficult to catch, but a trickle of steam coming out through a special hole near the top of the lower vessel will clearly indicate that the boiling water is ready.
4. Remove the machine from the fire and wait a few seconds, so that the water stops bubbling. Turn the entire structure over now in the correct position, being careful not to touch the heated parts, and place on a fireproof coating. In about three minutes, the water will pass through the ground coffee and accumulate in the lower collecting vessel.
5. If the spout of the receiving vessel is near its bottom, tilt the appliance and pour the first cup of coffee. This will help stir the mixture that has not yet passed through the filter. If the spout is high, wait until , disconnect the upper part of the device, mix the finished drink and pour it into cups.

Despite the fact that the Neapolitan coffee maker is designed for contact with an open fire, do not try to keep the finished drink hot by keeping it on a working burner, as this will inevitably lose the unique taste of fresh coffee.

Varlamov A., Balestrino J. The physics of coffee making // Kvant. - 2001. - No. 4. - S. 2-7.

By special agreement with the editorial board and the editors of the journal "Kvant"

A traveler wandering from one country to another may notice that in our age of standardization and the dominance of transnational monopolies, when the same soft drinks are served in New York and Kathmandu, the coffee market remains surprisingly colorful and varied. Drink from the same coffee beans prepared and drunk differently in Turkey and Egypt, in Italy and France, in Finland and the USA. Ordering coffee in a bar somewhere in Naples, you will get an elegant cup a little larger than a thimble, at the bottom of which a thick drop of almost black color slowly sways, covered with an appetizing foam. However, if you make the same order in Chicago, you will receive a half-liter plastic jar filled with brownish hot water. We do not undertake to judge which of the drinks is tastier or healthier, but simply discuss the various methods of making coffee and the physical processes associated with them.

boiled coffee

This is one of the oldest ways of preparing a coffee drink, which has survived to this day in the north of Scandinavia. Roasted and coarsely ground coffee is poured into water in the amount of 10 grams per 150-190 milliliters of water and boiled in a coffee pot for about 10 minutes. Then the drink is poured without filtration into cups and settled for several minutes. There is no interesting physics in this process, and the authors refrain from commenting on the taste of this drink.

Paper filter coffee maker

Such a coffee maker is widespread in the USA, in northern Europe, in Germany and in France. Its principle of operation is extremely simple, and the process of making coffee takes 6-8 minutes. Coarse ground coffee is poured into a conical filter made of special filter paper. Then hot water drips onto the ground coffee, “washes” it, seeps through the filter and collects in a glass vessel. The result is a light coffee drink: only a few coffee oils seep through the dense paper filter, and coarse grinding and lack of excess pressure do not contribute to the complete extraction of all coffee aromas. The American dose is 5-6 g of coffee per 150-190 ml of water, the European one is 10 g per cup.

"Turkish coffee"

The description of the process of making such coffee is already worthy of attention. Coffee beans are ground into dust (fine grinding), and this powder, often together with sugar, is poured into a metal (usually copper or brass) cone-shaped coffee maker called a cezve. Then she pours cold water and plunges up to the very neck into hot sand (according to a different recipe, ground coffee is placed on the surface of already hot water). The heating of the liquid occurs due to heat transfer from the sand through the bottom and side walls of the cezve. In the absence of sand, you can use the low fire of a gas stove, electric stove, etc. As a result of the heating of the bottom layers, convection currents arise: the hot liquid carries coffee particles up to the surface, where, due to surface tension forces, they linger and form a “coffee crust”. Gradually, the contents of the cezve are brought to a boil: bubbles break through the crust, foam forms. At this point, the cezve is removed from the sand (or removed from the stove), as boiling "kills" the coffee. The procedure for bringing the drink to a boil is repeated two more times, which leads to the formation of abundant foam. The resulting liquid is poured into small cups and wait until the sediment goes to the bottom. The result is a delicious thick drink, especially if the amount of water was relatively small.

The disadvantage of this method is the presence of a suspension of coffee powder in the resulting drink, which gradually settles to the bottom of the cup. There is even a way of divination on "coffee grounds".

Italian mocha

One of the most popular coffee makers home cooking coffee in Italy is mocha. It consists of three parts: a lower truncated cone (heater), where water is poured, a metal filter, where medium-ground coffee is poured, and, finally, an upper truncated cone, where the finished drink accumulates. This coffee maker is designed to prepare a drink of a certain consistency: water should be poured up to the level of the valve in the heater, the filter is filled up full - about 6 g per serving in 50 ml of water.

The process of making coffee in mocha is very entertaining. Coffee powder is poured into the filter and compacted, water is poured into the lower part of the mocha. Mocha is tightly twisted along the thread connecting the upper and lower cones. (The upper strainer covers the filter cylinder. Additional insulation from the external environment is a rubber gasket laid between the upper and lower cones.) The coffee maker is placed on a low fire. The preparation process consists in bringing water to a boil in the heater, then running it through coffee powder, further lifting the drink prepared in this way through the tube and draining it into the volume of the upper cone. After that, the coffee is ready for pouring (through the spout) into cups.

Everything seems simple and clear. But what is the “driver” of the described process? Of course, fire. First, the water is heated to a boil, then the process of boiling begins in a closed volume, where the water is given much more space than the steam above its surface. The temperature passes through 100 °C, the steam above the water surface always remains saturated, its pressure exceeds 1 atm and continues to grow. The external pressure, up to the upper level of the filter, is equal to atmospheric. Saturated steam with a temperature above 100 ° C begins to play the role of a compressed spring, pushing slightly superheated boiling water through the coffee powder contained in the filter. At the same time, all those aromas, oils and other components that turn water into a wonderful drink are extracted from coffee. It is clear that the properties of this drink depend both on the coffee powder itself, which is in the filter, and on the temperature of the water and the time it flows through the filter. The secrets of preparing a mixture of coffee beans, their roasting and grinding are the secrets of each manufacturer, based on talent, work and centuries of experience. What determines the time of liquid flow through the filter, we can understand without industrial espionage, based only on the laws of physics.

In the middle of the nineteenth century, French engineers A. Darcy and J. Dupuy made the first experimental observations of the movement of water in pipes filled with sand. These studies laid the foundation for the creation of the theory of filtration, which today is successfully used to describe the movement of liquids, gases and their mixtures through solids containing interconnected pores or cracks. In addition to creating the first perfect water supply system in Europe in the city of Dijon, Darcy formulated the so-called linear filtration law, which today bears his name. It relates the volumetric flow rate of the liquid Q through a sand filter whose length L, and the area S, with water level difference Δ H above the filter and at its base:

\(~Q = \frac(k_f S \Delta H)(L)\) .

The filtration coefficient included in this formula k f depends both on the nature of the porous medium and on the properties of the flowing liquid. These properties can be easily separated:

\(~k_f = \frac(k \rho g)(\eta)\) .

at the same time passing from the level difference characterizing a specific filter to the pressure difference on both sides Δ R = ρqΔ H:

\(~w = \frac(k)(\eta) \frac(\Delta p)(L)\) .

Here \(~w = \frac QS\) is the so-called filtration rate, which shows how much liquid flows through a unit area of ​​the filter surface per unit time, the coefficient η characterizes the viscosity of the liquid, and the coefficient k is a characteristic of only a porous medium and is called the permeability coefficient (it has the dimension of area). It should be noted that permeability, expressed in SI units, is usually very small. So, for coarse sandstones it is 10 -12 - 10 -13 m 2, for tight sandstones 10 -14 m 2. In the oil field, a special unit is used for the permeability coefficient - darcy (D): 1D \u003d 1.02 10 -12 m 2.

Let's try to apply Darcy's law to the study of our mocha. For example, it is interesting to know to what temperature the boiling water at the bottom of the coffee maker overheats. Let us estimate the pressure difference between the lower and upper sides of the filter using the Darcy formula:

\(~\Delta p = \frac(w \eta L)(k) = \frac(m \eta L)(S \rho kt)\) .

The characteristic dimensions of the filter for mocha for three servings are as follows: L= 1 cm and S= 50 cm 2; mass of coffee m= 150 g runs over t= 3 min. We can take the permeability coefficient of the same order as for coarse sandstone: k≈ 10 -13 m 2. Density of water ρ \u003d 10 3 kg / m 3. One must be careful with viscosity, as it is highly dependent on temperature; nevertheless, in tables of physical quantities one can find that η (100 ° C) \u003d 10 -3 Pa s. As a result, we get Δ R~ 10 4 Pa. The corresponding boiling point of water, according to the well-known plot of saturation vapor pressure versus boiling point, is T* = 105 °C.

So, we figured out the normal process of making coffee in an Italian mocha. However, there are grim rumors that at times these coffee makers go rogue and turn into bombs, threatening kitchen ceilings and walls, not to mention coffee drinkers nearby. Why and how can this happen?

It is clear that, first of all, the emergency valve made in the lower part of the mocha can become clogged or oxidized precisely in order to release steam in case of unplanned overheating. Therefore, old coffee makers become dangerous. The second reason for the "catastrophe" may be the obstruction of the filter itself, filled with coffee powder. There may be various reasons for this. The most exotic, in the spirit of a detective about the life of the Neapolitan mafia: a sophisticated killer clogged the upper tube with drunk coffee left in an unwashed coffee maker from yesterday. More realistic is this: densely packed (unknowingly to make it stronger) coffee powder too finely ground for mocha becomes impervious to water. Under the action of continued heating, the pressure in the lower vessel will grow unacceptably high, the water will break through a channel in the filter and tear the top of the coffee maker off the thread. What is the reason for such impermeability of the filter?

It turns out that the whole point is the limited applicability of Darcy's law. Indeed, the linear law of filtration is written without taking into account capillary phenomena. A porous medium can be represented as a complex system of interconnected voids and capillaries. A liquid can flow through a capillary with a radius r only when the pressure difference at the ends of the capillary exceeds \(~\frac(2\sigma)(r)\), where σ - coefficient of surface tension. The pressure difference at the ends of the capillary can be estimated as \(~\frac(\Delta p)(N)\), where Δ R is the pressure difference across the filter, and N- the average number of capillaries that fit on the thickness of the filter. Take for evaluation N~ 10, ∆ R~ 10 4 Pa, σ = 0.07 N/m. We obtain that already at the average capillary radius r~ 0.1 mm, some of them may be blocked for the flow of liquid at a normal pressure difference across the filter.

At first glance, there is nothing wrong with this - after all, some of the capillary pores will turn out to be of a larger radius and will be able to pass liquid. However, a closer analysis shows that this may not be enough. It is necessary to require that the fraction of open pores be greater than some critical value. Otherwise, the open pore system will not permeate the filter from one boundary to the other; moving through these pores, we can only take a few steps and inevitably run into an impenetrable capillary. It is said that in this case the system of open pores lost its “connectivity” and ceased to permeate the entire space, it was split into many small groups of pores connected to each other (such groups are called clusters).

The properties of systems with broken or limited connectivity are studied by a special section of statistical physics called percolation theory (from percolation- leakage). The critical concentration (share) of elements at which the system loses connectivity is called the percolation threshold. The theory of percolation studies not only the conditions for stopping the flow (current, fluid) through the system, but also the properties of the so-called weak flow, i.e. just above the percolation threshold (when the flow goes through a small number of through capillary passages). It turns out that the dependence of the flow rate on the concentration of free pores (which in our case depends on pressure) has a complex power-law character (with a fractional exponent), i.e. is not at all like Darcy's law, which comes into force only when the flow occurs through a developed system of permeable pores.

But back to our coffee filter. In this case, the proportion of permeable pores depends on the pressure difference across the filter and on the average pore radius, which, in turn, depends on the degree of coffee grinding. With excessive grinding of the powder, the average pore radius decreases, and their number on the filter thickness increases; as a result, the system may be impermeable up to a threshold pressure difference of several atmospheres. And then the following may happen. In a filter compressed by excess pressure, the average pore radius will decrease even more, which will lead to an increase in the threshold pressure difference, and this will further press the coffee in the filter ... In short, a vicious vicious circle is formed: the temperature in the lower vessel will increase, along with her pressure will rise. Finally, at a certain pressure, the water will nevertheless break through a channel for itself and break through the filter. At best, you will get bad coffee - after all, only a small part of the powder was used, and the temperature is too high. At worst, the pressure will rise so much that the thread will not withstand, and the coffee maker will explode.

Let's estimate the maximum (theoretical) damage that a mocha can cause by turning into a heat bomb. We will proceed from the worst: everything that could become clogged is clogged, and 150 g of water are heated in a closed volume, not much larger than the volume of the water itself. At a temperature of the order of critical (where the vapor density is compared with the density of water), which for water is equal to T k \u003d 373 ° С \u003d 646 K, all water will turn into steam. Further heating is possible, but the mocha itself will begin to glow - this has never been seen before. So, for the marginal estimate, let us assume that the corked mocha is heated to a temperature of the order T= 600 K. Having written the Mendeleev-Clapeyron equation, one can easily estimate the pressure in the lower part:

\(~p = \frac mM \frac(RT)(V)\) .

Assuming m= 150 g, V\u003d 200 cm 3, M= 18 g/mol, R\u003d 8.31 J / (mol K), we find that R~ 10 8 Pa \u003d 10 3 atm - this is a pressure of the order of the pressure at the bottom of the Mariana Trench. And the energy stored in a coffee maker at this temperature is an impressive \[~E = \frac 52 pV\] ~ 50 kJ, so the explosion would have dispersed individual parts of the mocha to speeds of the order of hundreds of meters per second.

From the above estimates, it is clear that the thread will not withstand much earlier. But the powerful force stored in the coffee maker due to excessive heat is also obvious: it is really more than enough to not only splash the entire kitchen with a failed drink, but also cause other troubles. So keep an eye on the valve, choose the right coffee grind, pour it into the filter without a slide and, most importantly, do not tamp.

Coffee in mocha is strong and aromatic, without sediment, but still inferior in its palatability espresso coffee served in a good bar. The main reason for this, apparently, is the relatively high temperature of boiling water forced through the filter by superheated steam. Therefore, the recipe for improving the quality of coffee when preparing it in mocha is as follows: put the coffee maker on a very low fire. In this case, the filtration process will be slower, however, the steam in the lower vessel will not overheat too much.

Probably, very good coffee can be made in a mocha, being in a mountain climbing shelter: there the external pressure is noticeably lower than 1 atm, and, for example, at the height of Everest, the water boils at 74 ° C - so overheating the water in the mocha will just bring the temperature to the optimum 90 - 95 °C.

Antique Neapolitan coffee maker "Napoletana"

This coffee maker resembles a mocha, but uses gravity filtration instead of pressurized steam filtration. It also consists of two vessels placed one on top of the other, and a filter filled with coffee between them. The water in the lower cylinder is brought to a boil, then the coffee maker is removed from the heat and turned over. Filtration occurs under the pressure of a water column of the order of several centimeters, so that Δ R does not exceed 0.01 atm. The process of making coffee here is noticeably slower than in mocha. We can experiment with making the same amount of coffee in both coffee makers and, based on the inverse proportionality of coffee brewing time to applied pressure, based on Darcy's law, check our previous estimate of the pressure in the mocha heater. However, in practice for "Napoletana" coffee is chosen with a coarser grinding than for mocha, otherwise the drink will be ready only after half an hour and will turn out to be cold.

Connoisseurs say that coffee from Napoletana is tastier than from mocha: there is no detrimental effect of overheated boiling water on coffee.

However, the high pace of modern life does not leave time for a philosophical conversation on the terrace overlooking Vesuvius and the beautiful Gulf of Naples, in a pleasant expectation, when you finally get a cup of healthy drink. This luxury remained in old paintings from Neapolitan life and in the creations of Eduardo de Philippe.

"Espresso"

Not all Neapolitans were patient even in past times. They say that in the last century, one of those residents of the capital of the kingdom of the Two Sicilies, who could not calmly wait at Napoletana, convinced his friend, an engineer from Milan, to design a fundamentally new coffee maker that prepared an individual portion of a wonderful aromatic thick drink for half a minute.

Every cup good coffee is a repository of the secrets of growing and harvesting coffee beans, preparing the mixture and roasting it, grinding... Behind the pinnacle of coffee art - a small cup of Italian "espresso" - there is also high technology. The espresso maker, which is also called espresso, is much larger and more impressive than its counterparts described above. Typically, such machines are found in bars and restaurants, but for connoisseurs and coffee lovers, there are also home versions of this machine. The company "La Pavoni", which has been producing such coffee makers since 1905, is one of the oldest, and its products are known all over the world.

In espresso, water with a temperature of 90 - 94 ° C is forced under a pressure of 9 - 16 atm through a filter with coffee powder of special grinding, even finer than for mocha. The whole process takes 15-25 seconds, resulting in 1 - 2 servings of coffee, 20 - 35 ml each - for you personally and maybe for your interlocutor. The process of liquid flowing through a filter with coffee powder is described by the same Darcy law as in mocha, however, the pressure difference applied to the filter is ten times greater here, and the temperature, on the contrary, is below 100 °C. These parameters are specially selected in such a way that the high temperature does not destroy the unstable fractions of the coffee drink. The relatively short time of interaction of water with the powder, together with high pressure, leaves everything superfluous in the powder and extracts all the best from it: coffee oil emulsions form the density of the drink, which cannot be achieved in any other way; its aroma is preserved by the presence of a foam that does not allow the volatile components to disappear. "Espresso", oddly enough, contains less caffeine - due to the short contact of water with the powder (20 - 30 seconds versus 4 - 5 minutes) in the filter and the smallness of its volume, all the caffeine does not have time to be extracted.

The first espresso was exhibited in Paris in 1855. In modern stationary devices that make up the equipment of bars and restaurants, water is supplied under the necessary pressure using a special pump available in the design. In a classic espresso machine, hot water from the heating cylinder, when the handle is raised, fills the chamber above the filter and is then pushed through the filter manually by lowering the handle; high pressure is created due to the dynamic resistance of the coffee filter and the effect of a lever that multiplies the force of the hand.

It is interesting to observe the behavior of the coffee stream flowing down from the spout as the cup is filled. At first, this jet flows well, then weakens and at some point turns into drops. The authors observed the same phenomenon in the mountains: the sun warmed the snow on the roof, and a stream of melt water flowed down the icicle either in a stream or a drop. Let's try to estimate the critical volume flow of water Q k , at which the mode change occurs. For simplicity, we will talk about the icicle, although the results will be applicable to the coffee maker.

Let the stream of water slowly flow down the icicle. It is clear that as long as the volume flow of water is very small, the jet will not work. Indeed, at the end of the icicle, water will collect into a drop, the drop will slowly grow, reach a certain critical size, break off ... and the process will repeat. Since we agreed that the water consumption is very small, the process can be considered almost static. Under equilibrium conditions, the detachment of a drop occurs when its gravity mg exceeds the surface tension force \(~F_(\sigma) = 2 \pi \sigma r\) acting along the perimeter along the constriction (we designated its radius r):

\(~mg = 2 \pi \sigma r\) .

The time of "filling" such a drop is obviously equal to

\(~t_k = \frac(m)(\rho Q_k)\) .

It is clear that the process of detachment of the drop also takes some time. The drop under the action of surface tension and gravity is almost in a state of equilibrium. But when its mass reaches a critical value and the surface tension can no longer compensate for the force of gravity, the bridge breaks. Typical jumper break time τ can be obtained from considerations of the theory of dimensions: a liquid with viscosity η must be moved a distance of the order r under the action of surface tension forces with a coefficient σ . Let's write the equation:

\(~\tau = r^(\alpha) \eta^(\beta) \sigma(\chi)\)

and compare the dimensions of the right and left sides:

C \u003d m α (kg / (m s)) β (kg / s 2) χ.

From here we get

\(~\begin(matrix) 1 = \beta - 2 \chi \\ 0 = \alpha - \beta \\ 0 = \beta + \chi \end(matrix)\) ,

\(~\alpha = \beta = -\chi = 1\) ,

\(~\tau = \frac(r \eta)(\sigma)\) .

Now it is clear that the change in the regimes of the droplet and the jet occurs at such a volumetric flow rate of water, when the next drop does not yet have time to come off, as a new one already runs, i.e. at

\(~t_k \sim \tau\) , or \(~\frac(m)(\rho Q_k) = \frac(r \eta)(\sigma)\).

Expressing the mass of a drop from the condition of its equilibrium in terms of the force of surface tension, we find the final beautiful formula:

\(~Q_k = \frac(2 \pi \sigma^2)(\eta \rho g)\) .

However, operating not with the volumetric flow rate of water, but with the mass flow rate, one could immediately obtain this formula from an analysis of the dimensions and the remark that Q k should not depend on the size of the icicle tip (the icicle melts and the tip “adjusts”). In the case of a metal spout of a coffee maker, its size, in principle, can affect the value of the critical flow, but not much, so the estimate found for the icicle is quite applicable to the spout of a coffee maker.

Instant coffee

The constant rush of modern life has led to the emergence of instant coffee. It is made from real coffee, which is ground and kept at high temperature and very low pressure. The water sublimates, and the remaining powder is placed in vacuum packaging where it can be stored for a very long time without losing its properties. Before use, it simply dissolves in hot water.

Variations on the theme "espresso"

With an espresso coffee maker and a good coffee blend, you can make a whole range of coffee drinks. So, in an Italian bar you can get: caffe'ristretto- "shortened coffee", made with a normal amount of coffee, but less water; caffe'lungo- "long coffee", prepared with a normal amount of coffee, but more water; caffe'machiato- the same "espresso", but with the addition of a small amount of milk; caffe'coretto- "espresso" with the addition of liquor, whiskey or vodka. Deserves special mention cappuccino” -“ espresso ”, poured into the bottom of a medium-sized cup and poured on top of milk, whipped with hot steam to a state of airy foam. A good bartender can pour this milk over coffee so that the first letter of your name written in brown on a white background appears on the surface. Or you can just sprinkle the snow-white foam with cocoa powder or chocolate chips.

Finally, they say that in Naples in some places they still serve caffe prepagato. It looks like this. A well-dressed signor comes in with a companion or a friend and orders: “Three coffees! Two for us and one caffe prepagato". After a while, a tramp or just a poor man walks into the same bar and asks if caffe prepagato. And the bartender pours him a free cup of fragrant espresso. Naples remains Naples...

The Neapolitan coffee recipe is nothing exceptional, but this drink is famous all over the world and is considered unique. It is not the recipe that makes it so, but the method of preparation. Neapolitan coffee cannot be made without a special coffee pot - a geyser coffee maker. Outwardly, it resembles two vessels connected to each other with a “layer” of a small container with filters into which coffee is placed. Passing through this container, the water is saturated with the taste and aroma of coffee. The result is a fairly strong drink with a delicate foam. It is served hot.

Technology Features

As already mentioned, the main thing in Neapolitan coffee is the way it is prepared, but there are other secrets. If you want to get a truly tasty, aromatic drink, it is advisable to take into account all the little things.

• Any kind of coffee is suitable for making Neapolitan coffee, but not too finely ground. If the grind is very fine, coffee will fall into the main container, which will make drinking the finished drink not so pleasant. For this reason, medium grind coffee is preferred. However, many people prefer to use finely ground coffee, not being lazy to strain it later. This is also acceptable.
• Coffee will have a richer flavor if ground before brewing and stored in beans.

A geyser coffee maker needs to be able to use it correctly:

1. Pour water into the lower container (without a spout) up to the mark (no more and no less, regardless of how many servings of the drink you want to brew).
2. Pour the powder into the coffee container. The container must be full, but it is impossible to strongly compact the coffee in it, otherwise the liquid will pass through it for too long. But if the coffee is not tamped at all, there may be no foam, this also does not hurt to take into account.
3. Screw on the top tightly. Your safety depends on the reliability of the fastening.
4. Put the coffee maker on the stove or turn it on if you have an electric one.
5. After the characteristic hiss tells you that the drink is ready, remove the coffee pot from the heat and turn it over, wait until the coffee is filtered (this takes up to 15 minutes), then pour it into cups. In some modern geyser coffee makers, there is no need to turn over, since the liquid enters the upper part and remains in it already during brewing.

• It is advisable to pour coffee into warmed cups. This will allow him to stay hot longer and exude a charming fragrance.
• The quality of the water is also important for the taste of the drink, and for the life of the coffee maker. Therefore, before cooking, it is desirable to soften the liquid, for example, by passing it through a special filter.

Neapolitan coffee is often made black, but cappuccino or latte are also possible. However, they can only be cooked in a device with a special valve. In any case, Neapolitan coffee is a very strong drink, it is undesirable to drink it for people with a tendency to hypertension.

Neapolitan coffee recipe

• finely ground coffee (preferably for brewing in a cup) - 18 g;
• medium grind coffee - 12 g;
• softened water - 0.2 l.

Cooking method:

1. Fill the bottom of the coffee maker with water to the desired mark. The capacity of the tank may be different, if your coffee maker does not hold 200 ml, but more, then the amount of coffee should also be adjusted.
2. Mix approximately equal parts of fine and medium ground coffee (2 teaspoons each). Set aside a teaspoon of finely ground coffee for now.
3. Pour the blended coffee through a special tube into the container provided for it, lightly tamping.
4. Attach the coffee filter to the top of the water container.
5. Screw on the top tank tightly.
6. Turn on the appliance or put it on fire. After signaling that the drink is ready, turn the appliance upside down, if it is provided by the manufacturer (this information is contained in the instruction manual for your coffee maker).
7. Warm the cups and pour half a teaspoon of finely ground coffee into it.
8. Pour the prepared coffee into cups.

Serve Neapolitan coffee immediately after it has been made. It takes a long time to cook, and if not served immediately, it will turn out to be too cold and therefore less tasty.

If you wish, prepare Neapolitan sweet coffee, first a small portion, about 20 ml, should be poured as soon as it is ready, and whipped into foam with two tablespoons of sugar. This foam decorates the drink after it is poured into cups.

Neapolitan coffee almost always has a delicate foam, its rich taste and bright coffee aroma captivate. So do not be surprised that the method of preparing a drink, once used only in one place, is now known throughout the world.

Sergey Reminny, a coffee specialist, talks about the coffee culture from Naples, Italy.

"Caffetiera Napoletana". Behind it is a whole layer of culture of the bright and distinctive southern Italian region of the province of Campania - Naples. The "new city" of Neapolis or elegantly sounding in the local dialect as "Napule" is a land with a full-fledged coffee history worthy of a separate book I will return to this wonderful city in my stories, and today - a story about a GREAT, but almost a thing of the past coffee maker - "Caffetiera Napoletana".

This Neapolitan lady is not from these parts. In fact, she is French. Yes, yes, it was there that its prototype was born almost two centuries ago, and it was called the “French filter coffee maker” (“Caffettiera Francese a filtro”), sometimes adding the definition of “two-story” (“a due piani”).

How this French creation got to Naples is not known for certain, but since the influence of the French kings has always been strong in these parts (since the time of the Sicilian kingdom), in general, there is nothing surprising in such assimilation.

Every third after the words "traditional Neapolitan coffee maker" he tried to show me moka (most often Bialetti), being completely sure that this is the famous “caffetiera Napoletana”. Oops ... Here, with sadness (or maybe not with sadness), we must admit that in Neapolitan houses, where Bialetti moka began to penetrate from the second half of the last century, the latter won an almost unconditional victory. Moreover, Neapolitans (like many Italians in general) believe that only Bialetti can be a moka - the image of this brand is so strong...

There are reasons for this - traditional moka is more convenient in almost all aspects, but there is such a thing as TRADITION. It is thanks to her that the "Neapolitan" is still alive. Although memories of her are becoming more and more the lot of older generations ...

Virtually every family that has a caffettiera Napoletana also has a moka. One Neapolitan taxi driver defined the purposes of their use as follows: “In mocha we make coffee when we want to make a small amount of coffee - only for ourselves or a maximum - for ourselves and one more person. And from “napoletana” - when a company comes, or just when a lot of people drink coffee. But, for example, my wife, who drinks 7-8 cups of coffee a day, prepares it from “napoletana” just for herself.

And since “Napoletana” is usually large, she prepares a full coffee maker, pours some of it for herself, sugars and drinks, and leaves the rest and drinks it right cold a little during the day ”(here I note that other narrators still reheat this coffee, although they prepare it in exactly the same way "in reserve").

In fact, "napoletana" is one of the variations of filter coffee makers and uses the physics of boiling water and gravity. By the way, within the species "Napoletana" there are a huge number of subspecies of coffee makers.

The outstanding Neapolitan film actor Eduardo de Filippo in the comedy "Questi fantasmi" ("Ghosts") in the famous scene with coffee, he sits on the balcony and is most colorful describes the poetry of the Neapolitan coffee maker, with "cuppetiello" on her nose.

I watched this episode ten times in a row, at least. And I watch it over and over from time to time. Because, my God, with what love de Filippo talks about making coffee! And in general, in my opinion, this scene is the BEST coffee scene in EVERYTHING of world cinema. I am 100% sure of this ... Of course, to fully understand it, you need to know the Italian language and hear Neapolitan specifics of speech, but even without this, the episode is permeated with a love for coffee that is impossible not to feel...

Apparently, this is because, as the Neapolitans say: “A che bellu cafe sol a napl o san fa!” -

One Neapolitan guy told me that he remembers from childhood how his grandmother, when she made coffee for herself, gave him a piece of bread (crust) with a drop of coffee and a little sugar on it, and for many years it was a kind of lunch treat for him .. Well, where else can you find such memories?.."

If you love coffee, then most likely you will like Italian coffee. There are many different types, including espresso and cappuccino, which are popular all over the world. All types of coffee are based on espresso. For example, cappuccino is espresso with frothed milk and milk foam.

Please note that "espresso" is not an Italian term used worldwide. What we call "espresso" is just "coffee" in Italy (stress on the second syllable). On our page, we use the more familiar term "espresso". Just remember that in Italy the correct term is coffee.

If you want to make true espresso, then be prepared to spend a few hundred dollars on a high quality espresso machine that you might see in restaurants or cappuccino bars. These machines use high pressure water (9 bar) to produce espresso. Home machines, even the $100 models available in stores and elsewhere, don't produce enough pressure to produce the kind of espresso you can drink in coffee bars. (Cheap models tend to produce around 4 bar, while more expensive models can produce 15 bar. Although 9 bar is sufficient for espresso.)

A very reasonable alternative for home use is the Geyser coffee maker, called moko in Italy. A moka is a simple device that uses steam pressure to force water through an espresso filter. It won't be like the espresso you get in bars, but it will taste about the same. So, the Geyser coffee maker is an inexpensive and best alternative for making good coffee. Myself

Moka, or geyser coffee maker, is often mistakenly referred to as an espresso coffee maker. This is wrong, only espresso machines are capable of making espresso. Another misconception is that water is brought to a boil. The result is a bitter drink. If you follow all the rules and recommendations, then you can get a great drink in it.

Story

Moka was patented by Alfonso Bialetti in 1933 and sold under the name "Moka Express". It became popular only after the Second World War. It had a very recognizable design that has not changed to this day, and was made of aluminum. (Bialetti has been a market leader for over 50 years with the famous Moka Express coffee maker. Thanks to some technological secrets, this coffee maker is the ultimate device for real Italian coffee. The Moka Express Bialetti coffee maker is an original product if it has an image of a man with a mustache printed on it. Always ask for such an image.)

The geyser coffee maker, from a technical point of view, functions on the same principle as the coffee percolator, which is the forerunner of the siphon and pressure coffee makers. Coffee percolators worked on the principle of pushing water under steam pressure from the lower compartment into the second compartment, where the coffee is located and then, the ode seeps down into the third compartment, from where it is poured into cups. These units required almost no human intervention, which was quite convenient, given that they first appeared in 1820.

Moka was different in that the water did not seep down, but up. The pressure in the upper part of the lower water tank contributes to the movement of water into the coffee compartment, and then through a special channel into the upper third compartment, where the ready-made coffee enters. The first inventor of such a mechanism for obtaining coffee was the Englishman Samuel Parker in 1833. It was Bialetti's Moka Express that made it popular. For 10 years, more than 20 million geyser coffee makers have been sold.

How to use a geyser coffee maker

If you use this coffee maker correctly, you can get very tasty coffee. However, this method has some features that should be taken into account. Geyser coffee makers come in a wide variety of sizes, from tiny to prohibitively large. You need to be especially careful with large coffee makers. If your heat source is insufficient, it will take longer to brew coffee, which in turn will make it overextracted. A large coffee maker needs a coarser grind and longer brewing time, otherwise the astringency and expressiveness of the taste will be lost as a result of over-extraction. In some geyser coffee makers, a valve is installed that allows water to flow upwards when the desired pressure is reached. It is also recommended to brew coffee at once in the maximum volume. This is due to the fact that a small amount of water is quickly squeezed out by steam upwards, without having time to heat up to the desired temperature.

Making coffee in a geyser coffee maker is a kind of art, if everything is done correctly, the result will exceed all your expectations. Medium to dark roasted coffees are best for moka, but light roasted espresso beans can also be used.

Operating instructions for the Moka Express coffee maker from Bialetti

The Moka Express coffee maker from Bialetti is made of aluminum alloy and can be used on any heat source. There are 8 product modifications of different sizes: based on 1, 2, 3, 4, 6, 9, 12 and 18 servings (cups).

Application

Fill the bottom part (1) up to the safety valve (6) with water, insert the funnel filter (2) and fill it with ground coffee without tamping. Make sure the filter plate and gasket fit into their respective slots, then screw the top part (3) tightly to the bottom part (1). Put the coffee maker on the fire and after about 4 minutes coffee with a strong aromatic smell will start to flow out of the column (4). When the coffee has filled the top container (3), remove the coffee maker from the heat.

Do not use various extracts, as they may clog the filter of the coffee maker. Regularly check the condition of the coffee maker by changing the wear parts to be replaced (2,5). When the threaded parts (lower part 1 and container of the upper part 3) wear out, it is recommended to replace the coffee maker. Do not tamp the coffee in the filter. Use soap and water to clean the coffee maker; other detergents may damage the aluminum surface. Liquid detergents for metals may be used to maintain the gloss. Clean the inside of the post (4) thoroughly from time to time. Before using the coffee maker, check that the valve and all internal components are present and correctly installed. The coffee maker is guaranteed for a period of two years.

The new model of the valve will help to avoid calcium clogging from water: it is enough to move the piston protruding from the valve along its stem during the normal washing of the coffee pot.

Some parts of the Geyser Coffee Maker are replaceable. After a few months of use, you may need to replace the rubber gasket or the entire filter. When emptying the mesh used coffee grounds don't hit her. This can mess up the mesh. Instead, rinse it under water.

Cooking coffee in a geyser coffee maker

For cooking, we need a fine grind.

1. It is necessary to pour water into the bottom of the coffee pot up to the mark or up to the safety valve. If your moka does not have a valve, you must first boil the water.
2. Prepare ground coffee and place it in the filter. (I usually don't fill the filter all the way, as this will be a very strong coffee for me.)
3. Assemble the entire structure together.
4. Place the coffee pot on the stove over medium heat. Open the lid and watch the preparation: the water will boil and the top tank will begin to fill with coffee. You can control the process by lowering the heat, which will allow you to control the extraction process.
5. As soon as bubbles begin to appear, this will mean that steam has begun to rise to the top, which means that you need to remove the coffee from the fire.
6. Quickly pour water over the outside of the coffee pot to stop the coffee brewing process.
7. Pour the coffee and let it cool down a bit.

Neapolitan method of making coffee in a Geyser coffee maker

Below is the Neapolitan coffee preparation method. Foam, usually created by a machine, is produced by hand in this method. Attention! 50 grams of espresso has about the same amount of caffeine as a 200 gram cup of regular coffee. Don't get into the habit of drinking a 200-gram cup of espresso during the day (but you can if you don't want to sleep during the day).

To make Italian espresso you will need: good quality espresso (popular Italian brands are Illi and Kimbo), sugar, cold water, a geyser coffee maker, an espresso mixing container and small cups (preferably ceramic espresso cups).

Step 1 Fill with cold water

Fill the Geyser Coffee Maker with cold water. The inside of the coffee maker is usually marked with a line showing the water level. If not, then fill it up to the safety valve located on the side wall of the tank. Water must not seep through the filter. This may affect the taste.

Step 2 Insert the filter into the water tank

Insert the filter into the water tank. (Alternatively, you can fill the filter with ground coffee first and then insert it. It depends on personal preference).

Step 3 Add coffee beans

Fill the filter with ground coffee. Make sure you don't spill ground coffee on the outer edge of the container. Everything must be perfectly twisted, otherwise the water will come out as soon as it starts to boil. Before assembling the coffee maker, simply remove all excess particles. This is one of the reasons why some people fill the filter first and then put it back in place.

Attention: do not tamp the coffee! This can create excessive pressure. While this is common on commercial machines, it is dangerous for these coffee makers.

This is how the ground coffee filled with the filter should look like. Collect the grind in the shape of a mountain, as in the picture. Thus, you will enhance the flavor of the drink. You can assemble it to your liking if that amount of coffee is too strong for you.

Step 4 Assemble the coffee maker

Assemble the coffee maker. Once again, make sure there are no grains on the outside. Screw the top to the bottom, holding the coffee maker itself with your hand, not its handle. Handles can break easily (but are also replaceable).

Step 5 Place the coffee maker on the stove

Place the coffee maker over the stove under low heat. Low heat increases the brewing time, which enhances the flavor.

Step 6 Prepare Sugar

While the espresso is brewing, add the sugar to another mixing container. You can start with a teaspoon per cup, and then if you don't like it, you can change the proportion to suit your taste. The coffee pot in this picture is a 10-cup pot, so we added just over ten teaspoons. After some practice, you will be able to simply and easily add right amount sugar into a container without measuring it. Remember that espresso is an art, not a science.

Step 7 Pour coffee and mix with sugar

This step is critical and may require some experience to get it right. As soon as the coffee begins to pour out, remove the coffee maker from the stove and pour some of the drink into a container for mixing with sugar.

It's better to add less coffee than too much, so be conservative. After pouring coffee to sugar, start mixing them. The end result will be a liquid solution. If it's too thick, keep adding the coffee little by little until you get the right consistency.

If you run out of coffee, put it back on the fire until more comes up. You should use the first drink from the coffee maker as it is the strongest. Don't try to brew the whole coffee maker and then add it to the sugar. That won't give you the right taste.

It's about the right consistency. If you accidentally add too much liquid, you can then add more sugar (not recommended if you don't have a sweet tooth) or just add the rest of the coffee at the end of the brew. It won't have much foam on top, but it will still be drinkable.

By the end of the brew, the coffee comes out mostly in the form of steam. The coffee maker shown here has a tube designed to minimize splashing during the brewing process. The lid can remain open during cooking. Other models may have two holes on the side and will spray coffee all over the kitchen if the lid is up.

Step 8 Pour More

When the coffee has finished brewing, pour about half of it into the mixing container.

Step 9 Stir, add remaining coffee and stir again.

Stir vigorously to aerate the mixture and get plenty of foam. After mixing thoroughly, add the remaining coffee to the container and stir again.

Final result. The amount of foam produced depends on the technique and the amount of sugar used. With a little practice, you can make the perfect coffee every time, just like a Neapolitan.

Step 10 Serve and Enjoy

The best part. Pour coffee into small ceramic cups. You can use a spoon to add foam to the cups if necessary.

Since the cups are small, the espresso can cool down quickly. To keep the cups warm, place them in hot water just before drinking coffee from them. When you pour coffee into hot cups, they will keep warm and allow you and your friends to enjoy a hot, excellent drink.