An espresso machine must provide 9 bars of water pressure to brew espresso and to froth or steam milk. Professional machines can use either a heat exchange boiler – this is the most widely used espresso machine.
This type of boiler heats water using a steam boiler. In these machines, groups are heated with coffee water circling from heat exchange to the groups and back.
A dual boiler espresso machine separates the water used to brew espresso from the steam boiler; each has its own heating elements, and you can adjust them separately. In these types of machines, you can adjust the water temperature to suit your coffee. The powerful heating elements also ensure that there is always a supply of hot water on demand with little difference between shots.
Dual boiler machines are exceptionally advantageous and come with many pros to offer you more control when brewing espresso. Let’s explore the full benefits of dual boiler machines to find out of they are actually necessary. We will also investigate how they compare to heat exchangers.
What Is The Benefit Of A Dual Boiler Espresso Machine?
A dual boiler espresso machine has two separate boilers, one that brews the espresso and the other to offer steam for steaming or frothing milk.
Up-to-date models feature a digital control on the brewing temperature component – this allows a more accurate temperature adjustment for different types of coffee. In addition, this machine handles two essential facts about espresso:
1. Espresso needs two different temperatures
Firstly, you need two different temperatures to brew espresso; you need one temperature for making it and another for steaming.
The milk foam on top of a cappuccino or latte is crucial for those beverages. You need the right temperature to produce the quintessential foaming effect, and getting it right calls for high-temperature steam.
However, the temperature for brewing beans should be much lower; about 200 degrees Fahrenheit is sufficient. The optimal temperature difference shows independent heating is needed for the two elements of espresso.
2. The temperature must be optimal
Secondly, the optimal temperature is necessary for extracting flavor. This seemingly minor detail is essential to obtaining the full espresso experience. A coffee change often calls for a temperature change, and slight adjustments can make an enormous difference.
Is A Double Boiler Necessary?
A double boiler is a must-have for individuals that make a lot of milk-based coffees and plain espressos. Also, if you change your beans often, have a sensitive palate and prefer delicate single-origin beans. A double boiler is crucial as you have improved temperature consistency and control.
Consider how this machine works and the magic it produces to create espresso or milk-based coffee:
- The machine pumps cold water into the steam boiler and the brew boiler via the reservoir or direct water line connection.
- Usually, you can adjust the temperature of each boiler separately. The steam boiler heats water to steam temperature, while the brew boiler heats the water to brew temperature.
- After you pull your shot, the temperature in the brew boiler and group head remains consistent and is typically ready to pull another shot straight away.
- After you are finished steaming your milk, your machine may need some recovery time, depending on the model you are using. However, milk for another drink can be steamed with little downtime.
Consider the pros, in a nutshell, to understand how essential these machines are to the espresso-brewing process:
- Different brew and steam temperature adjustments.
- Has consistent brew temperature
- No cooling flush required
- Brew and steam simultaneously with no wait between brewing and steaming or frothing
Which Is Better Double Boiler Or Heat Exchanger?
Whether you decide to get a double boiler or heat exchanger depends on your consumption level and expectations. We understand that the double boiler has two boilers on a single machine, and each one has an essential function.
The brew boiler is at a lower temperature, while the steam boiler is at a higher temperature. Keeping them separate allows you to have complete control over the brew temperature and more consistency in extraction.
The heat exchanger has just one boiler, and it is set at steam temperature. It contains a smaller boiler inside. This is a heat exchanger rod that passes through.
The pump flushes cold water from the water sources when the extraction is complete. This passes it through the heat exchanger. Thermodynamics and hydrodynamics allow the water to travel through the heat exchanger, and the water heats up. The water should heat up to a perfect extraction temperature.
Unlike double boilers that have independent boilers to make espresso with a stable temperature profile, heat exchangers have expected temperature fluctuations during the extraction process.
At first, water in the heat exchanger warms up to a higher temperature, and during extraction, cold water enters the heat exchanger to warm up while the hot water remains. The displacement of cold water passing through reduces the heat in the heat exchanger. What should happen is that the extraction temperature should have a gradual reduction.
Double boilers are more predictable to control, and even amateur baristas can create a consistent shot of expected quality. There is no more flushing or temperature guessing.
These machines improve consistency. Espresso should be balanced in bitterness and acidity with floral or fruity note blossoms and nutty profiles. This, however, is not to everyone’s taste, and a heat exchanger releases a broader spectrum of characters, which some prefer.
Water is the main component of espresso, and many Italians believe that freshwater is critical to good espresso, as freshwater releases a wider spectrum of flavors during extraction.
Double boilers draw the water from its brew boiler, here the water has little movement, and the same water is reheated from the day it functions until its last time of service. Heat exchangers only draw fresh water from the eater tank or network for extraction.
Maintaining a heat exchanger is relatively easy as it has only one boiler, one set of heating elements, and other components. However, a double boiler has numerous features to maintain, so servicing them is challenging and expensive. Also, two boiler machines take longer to heat up than the single boiler heat exchanger.
Final Thoughts
As you can see, there are good and bad sides to both heat exchangers and double boilers, yet each has an essential role, depending on the consumer’s needs.
The beans you use have a significant effect on the taste and quality of your espresso. Environmental conditions like heat, light, and humidity can deteriorate the quality of the beans. However, the main difference between a decent coffee and a lousy one largely depends on the barista, as coffee knowledge is crucial.
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