Test:Techniques

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Making your first espresso machine purchase can be a daunting task. A simple internet search for information regarding these machines yields an overwhelming amount of information. This article strives to condense this information into a more organized and manageable guide to machine purchasing. Being able to prioritize the factors that are important to you and understanding why they are important will help in choosing a machine that makes you happy and meets your needs.

Factors For Selection

As a starting point it is a good idea to establish why you are purchasing an espresso machine. Establishing expectations and understanding your needs before you make a purchase will ensure that you are getting a machine that can live up to those expectations. If you are new to the espresso home brewing experience then it can be hard to know what to expect. In this section we will explore the most common factors that go into the purchase of an espresso machine and why they are important.

User Experience

We've chosen to list this as the first factor because of its importance. If you have never used an espresso machine before, then going straight for a manually operated or prosumer style machine may result in a very unsatisfactory experience. The amount of control these machines offer, and their heavy reliance on the user's technique and ability can make them frustrating to use and make learning espresso extraction harder than it needs to be. Alternatively if you're an experienced user you may find some units, such as super-automatics, frustrating to use because of the lack of direct control you have over the process.

Convenience vs. Quality

Balancing convenience with quality ties in with user experience as well. Machines that are designed for convenience, such as pod machines, will be the simplest to use. They're relatively straightforward, and mainly just require you to insert a cartridge and select a brewing option. Moving up from there you have super-automatic machines and semi-automatic machines that utilize pressurized brewing systems. These machines offer a little more user control, but are still doing a lot of the work. Depending on the super-automatic machine the amount of user control can be fairly limited, while high end units off more. Since espresso brewing is all about controlling variables these types of machine can produce good tasting espresso, but it will not cafe quality. Their advantage though is that they offer a balance to convenience and quality - so if you are a new user, but want something that tastes better than a capsule, that uses freshly ground coffee these machines are a good choice. If shot quality is really your goal then it's really best to trade up the convenience factor in favor of more direct control. Manual, prosumer, and semi-automatic machines can offer this higher level of control. Manual and prosumer in particular will typically have many more control options, really giving them the best ability to produce a shot of espresso that wows you.

Another aspect of convenience that many people consider is how quickly a machine heats up. Generally smaller home units such as semi-automatics and super-automatics have shorter heat up times, typically around 10 minutes long. Some of these style machines will also feature rapid heat boilers, which means they are ready to brewing within just a couple of minutes of being turned on. These are great for people on the go. Semi-automatic machines with larger boilers, prosumer, and commercial machines will take longer to heat, anywhere from 15-30 minutes. Most prosumer and commercial units are designed to be able to be left on for long period of time or indefinitely though, so heat up time is not a factor if the machine is left on.

Frequency of Use

Selecting a machine based on how frequently it is used and many people are going to be using it is important because not all machines are rated to handle the traffic in a cafe or office, or are meant to be left on for extended periods of time. Many manufacturers will also consider the warranty on the unit void if used in a high volume if the machine is meant for home and personal use.

If you are only brewing a couple of shots a day then a semi-automatic unit, or small super-automatic unit will be sufficient. Likewise, if it's a family using the machines these will also work, but you may wand to get into a super-automatic with more programming options so that each person can easily brew their own drink. A semi-automatic unit will work as well, but if you have several family members brewing drinks in a row you may want to get a semi-automatic with a larger boiler to reduce recovery time between brewing and steaming.

For higher volume use, like in an office you will want to go for a large high quality super-automatic unit or a prosumer level unit that is rated for office use. Super-automatics are usually preferable in an office environment for those who are not familiar with the technique of espresso extraction. That being said, prosumer units are still popular choices for office environments and they are advantageous because they are designed to be able to be left on indefinitely. For very high volume usage, such as in a cafe, it is important to select a machine that will meet that demand. Some prosumer units will be rated for light commercial use, but for heavy traffic it's best to purchase a commercial unit. Commercially rated units are meant to be left on, and are usually powerful enough to brew and steam simultaneously, and have little to no recovery time.

Maintenance Needs

Every machine is going to require some sort of regular maintenance and cleaning, but what level of maintenance is required will vary from machine to machine. These machines are handling a food product, so to keep them functional and sanitary they need to be cleaned regularly. Skipping required cleaning and maintenance can result in machine failure or bad tasting coffee. Some units will require disassembling parts of the machine as part of the regular maintenance.

Some important questions to ask yourself when deciding on a machine are: How frequently do I want to have to clean the machine? What kind of cost will go into cleaning this machine? How comfortable am I as disassembling a machine? Do I want to be able to do most of the cleaning/maintenance myself, or do I prefer the machine be sent for service? Answering these questions will help point you in a good direction. Most machines are going to require monthly or weekly cleaning - some things will need to be cleaned daily. Some machines will be more automated in their cleaning, such as the higher end Jura Capresso units.

Understanding how willing you are to take apart a machine for the cleaning and maintenance is a good determining factor as well. On most home espresso units some simple disassembly is going to be required for proper cleaning and maintenance. This isn't usually anything complicated, typically just removing some screws and cleaning parts. On more complex units, such as Prosumer units, the cleanings will be a little more involved, and some cleanings are recommended to only be done professionally. Some machines, such as high end super-automatic machines are not user serviceable. If you prefer being able to clean and maintain a machine yourself these may not be a good choice, because they frequently make core components inaccessible and require professional service.

Materials

This is frequently more of an aesthetic consideration, but the material of functional parts does have an effect as well. For the most part internal parts are going to be metal within the espresso machine regardless of the type or quality of the unit. Tubing is frequently plastic, but on more expensive units the plastic tubing is usually replaced with copper piping, or braided stainless steel hoses which have higher durability. External paneling on most home units is going to be plastic, even on higher end home units. The exception are prosumer style machines, which frequently use metal paneling; they are styled after commercial unit, and metal is used both for aesthetics, but also to help the machine passively heat for features like the cup warmer. Super-automatics typically use a plastic brewing mechanism, while many machines utilize a metal grouphead.

The material of the boiler is frequently a consideration. The material of the boiler can affect how the boiler can be cleaned; aluminum boilers for example can't be cleaned with certain cleaners because they will be damaged. The material of the boiler also affects how quickly heat is transmitted and how quickly the boiler heats as a result. The material of the boiler also determined how susceptible it is to wear over time. Stainless steel boilers for example are less susceptible to corrosion. Low mineral content waters such as R/O water and distilled water can't be used with certain boiler materials, because the water can leech and degrade the metal.

Operating Space

This can get overlooked, especially for a first time purchase, but espresso machines, even the smaller home units, do take up a fair amount of space. The machines on our website will list exact dimensions so that you can measure your available space ahead of time to make sure you will have room. Think about how much additional space you need, such as for packing and tamping your portafilter, any accessories that you will need to go with the machine, or for a grinder.

Plumbing

If the machine is going to be plumbed in then a machine that is capable of this will need to be selected. Many of the smaller home units, such as semi-automatics and super-automatics will only utilize a built in reservoir are not plumb capable. Some higher end super-automatics are an exception, because they are designed for use in an office space. Prosumer machines frequently have a plumb option. Prosumer machines frequently come in different versions that are either plumb capable or not. Some will be switchable between a plumb line and a built in reservoir. Some machines can be converted to use a plumb line later, but these conversions are often complicated and pricey, so it is advisable to get the plumb option at the time of purchase.

Programmability

Espresso machines will vary greatly in the amount of software control that they offer. Super-automatic machines in particular offer a lot of programming options, because they are convenience based machines. Basic temperature adjustment, drink volume, beverage programming, frothing temperature and amount, grinder dosing amount, languages, and automated cleanings are some of the things the software on these machines support. Higher end super-automatics offer a lot of drink customization options.

Semi-automatic and prosumer units can offer some programming, but won't typically have this level of software programmability because these are more manually controlled units. Some of these units will offer options for programming beverage length. Some will also offer a very accurate temperature measurement tool called a PID. PID's are advantageous because the allow for very exact temperature control of the brew boiler; sometimes PIDs can also control the steam boiler temperature as well.

Sound Level

Espresso machines can be noisy machines. A large source of noise is the pump. Home espresso units in particular typically utilize a vibration style pump, which can be quite loud. More recently released home espresso units are a little quieter because the vibration pumps have better mounting that reduces the vibration and noise caused by these pumps. Rotary pumps run quieter than vibration style pumps, as well as offering more consistent pressures.

Super-automatic machines will tend towards the noisier side. In addition to using vibration style pumps they utilize built in grinding mechanisms. They also use a special brewing system called a brew unit. Brew units will make creaking and loud clicking noises as part of their normal operation, as well as a hum from the brew unit motor when it is engaged. Machines with mechanical grinder dosing systems will be louder, often making loud snapping noises as the doser engages to measure out the coffee. Machines with electronically controlled coffee dosing do not make this noise.

Power Considerations

Espresso machines, especially prosumer and commercial units, use quite a bit of power in their operation. The energy demand of the pump and the boiler(s) requires quite a bit more power than a typical home or kitchen appliance. Even small home units will typically use 1200-1400 Watt boilers. This means that espresso machines use quite a bit more amperage, so will require dedicated power. Make sure that your home is able to supply to kind of power needed for these machines. Typical power requirements are that the outlet be able to handle a load of 15-20 Amps. Not having an appropriate power supply can cause an espresso machine to malfunction or not turn on at all. The use of extension cords, surge protectors, and outlet timers is inadvisable because they are not rated to handle this kind of current demand.

Drinks Being Made

If you do not plan on making milk based drinks, and mainly want to focus on espresso, then it may be advantageous to purchase a machine that does not place as much focus on frothing. Some machines allow for the steam boiler to be turned off when not in use to reduce energy consumption. You may want to get a machine the features an auto-frothing capability instead of a manual frothing. These devices don't create as good of a microfoam as manual frothing does, but they are a convenient feature to have. Manual frothing requires a skilled hand. If milk based drinks are not something you will make often, or don't mind your froth having larger bubbles, or have inexperienced guests using the machine then this may be better choice than a manual frothing wand.

Machine Features

In order to understand if a machine is going to meet your needs and expectations then it is important to know what features it has available, how those features work, and what they provide.

Brew Features

These features pertain to the brewing functionality of the machine.

Pump Type

The two main pump types used in modern home espresso machines are vibration pumps and rotary pumps. There are advantages and disadvantages to each.

Vibration pumps cheaper and more compact, which reduces the cost and weight of the machine. This also allows for a easier working access and internal arrangement of machines parts. Since these pumps are smaller they are great for compact espresso machines. They are also much easier to replace. Most of the machines we offer utilize an Ulka branded vibration pump - these have become an industry standard because of their reliability. Vibration pumps do not produce as consistent of a pressure, needing time to build pressure when first activated. Since these pumps operate by vibrating they can be fairly loud. The pressure on these pumps also cannot be directly adjusted and operate at a standard design pressure.

Rotary pumps are a type of positive displacement pump. These pumps create pressure through rapidly rotating vanes, which force water through the system and create pressure as they rotate. These pumps are much bulkier, but work silently and provide a very consistent amount of pressure. Rotary pumps are also capable of having their set pressure adjusted directly. Rotary pumps are highly durable, and are designed for high volume use. Since they are a type of positive displacement pump it is optimal to have machines that use these plumbed in, with a positive pressure supplied to the plumb line. Since these pumps are bulkier and more complex they are harder to replace and take up more internal machine space.

Pressure Control

Some espresso machines offer brew pressure control, so that the brewing pressure can be adjusted during extraction. These will typically be higher end units such as prosumer or commercial machines. Recommended brew pressure ranges are 8-9 bar pressure during brewing. By adjusting the brewing pressure the resulting extraction will vary in flavor. Lower pressure will bring forward more of the sour, fruity, and floral notes. Raising the pressure will bring out more of the bitters of the coffee.

Some machines allow for pressure profiling. What this means is that through either a series of internal pressure controls, or manual control, you can directly control what pressure is applied by the system at different points in the extraction process. Pressure profiling is usually sought after by highly experienced users who are very familiar with the mechanics of an espresso extraction. Being able to control the brew pressure at different points in the extraction allows the user to bring forward certain flavors in the coffee to make them more pronounced, or hide unwanted flavors.

In order to properly read how the pressure is adjusted, and what pressures are being produces during brew many machines will include a brew pressure gauge on the front of the machine. These gauges only provide a meaningful reading when the machine is actively brewing or being backflushed.

On super-automatic style machines pressure is modified in a separate way. Some Saeco machine utilize a special type of brewing system called VariPresso. VariPresso systems use a special brew unit and tamping system that adjust how much pressure is developed during extraction. This means that for longer coffee the machine can be set to a lower pressure to create a more balanced extraction. Jura-Capresso also has brew control control on their super-automatic unites. Their machines use a Pulse Extraction Process brewing system. This system allows for better tasting short length coffees, because water is pulsed through the coffee grounds instead of forced through at constant pressure.

Brewing Style

For the most part most espresso machines are going to use a similar brewing process. A handle is filled with ground coffee and then attached to the machine. Where the handle is attached to is called the grouphead or the brew group. This is where water is injected from the boiler of the machine. The grouphead is responsible for evenly distributing the water over the coffee grounds. This is achieved through a part called the shower screen.

For many smaller home units the grouphead is basically a large cylindrical block of metal that sits directly below the boiler. On some machines it actually acts as the bottom half of the boiler. This lets the heat of the boiler passively heat the grouphead. During espresso extraction maintaining consistent temperature from boiler to cup is important for getting the best flavor. This type of grouphead is referred to as being passively heated.

There are also actively heated brew heads. There are different means in which they are heated. Some use actual heating elements that are built into the grouphead which heat it to a set temperature. Much more commonly is a style of grouphead called an E-61. Some semi-automatic, and many prosumer and commercial machines use a variation of this style of grouphead. This type of grouphead utilizes water that circulated through the grouphead by the static water pressure of the boiler when the machine is sitting idle. The main advantage of the E-61 style grouphead is the temperature stability it provides during extraction. A detailed article on all of the advantages of this grouphead style can be found here.

Some espresso machines, particularly semi-automatic machines use pressurized baskets and portafilter systems. They can be thought of as training wheels for espresso brewing. These systems add an additional layer of pressurization in addition to the coffee. These systems are good for new users, because they help compensate for defects in technique. Since these systems produce a false pressurization they will not be able to achieve the same quality shots as a normal non-pressurized shot basket. They're really meant as a learning tool - to truly master and perfect your shots you will want to graduate from these to a normal commercial style basket. Even if you are using a pressurized basket/portafilter system that does not mean you can completely ignore brewing technique. These systems simply help reduce how reactive the system is to the different brewing variable.

You can see a side by side comparison of non-pressurized vs. pressurized baskets below. The pressurized baskets will tend to produce larger bubbles, and there will be flavor differences.

Super-automatic style machines using a component called a brew unit which is quite different from the traditional grouphead. The brew unit, which is also referred to as the brew group, is responsible for both tamping the coffee, as well and infusion and distributing water evenly across the coffee grounds.

Pre-infusion is a feature of espresso machines in where the coffee is soaked with non-pressurized water before the active pressure is applied to the coffee. There's some debate as to the effectiveness of pre-infusion. The intended purpose of pre-infusion is to remove some of the inconsistencies in the coffee puck and assist in the water more evenly distributing through the coffee once pump pressure is applied to the coffee. Not all machine have the capability for pre-infusion, and the method of pre-infusion varies. While semi-automatic machines don't have a formal pre-infusion, because they typically utilize a vibration pump the slow ramp up in pressure works similarly to pre-infusion. Some super-automatic machines pre-infuse by turning the pump on for a short burst before fully activating the pump for extraction. Prosumer machines typically pre-infuse through a pre-infusion chamber in the grouphead that fills with water. The video below describes the function of a pre-infusion chamber on an E-61 style machine.

Temperature Control

Most home machines control brew temperature through a simple thermostat. This is a binary heating system - when the temperature is too low the thermostat tells the boiler to turn on to heat. When the set temperature of the thermostat is reached the boiler element switches off and will not be turned back on until the thermostat detects the temperature has dropped enough.

In single boiler heat exchange machines the brew temperature directly correlates to steam pressure. Brew water is heated in a tube that is surrounded by the outer boiler which is filled with steam and hot water. Whatever the steam pressure the machine is set to will determine the resulting brew pressure. The means that a raise in the steam pressure will result in a raise in the brew temperature.

The other main style of temperature control it through an electronic thermostat or PID. Electronic thermostats are similar to mechanical thermostats. They operate by a simple on and off function, but their set temperature can be programmed, giving additional control. PIDs are the most accurate method of controlling temperature, and produce the least amount of temperature variance. PID stands for Product Integral Derivative. This device uses several different equations to control the temperature through a static relay. A temperature probe tells the PID what the current temperature is. Based on the current temperature and the rate in temperature change the PID tells the static relay how much power to supply to the heating element. By modulating the amount of power going to the heating element there is much less risk of the temperature shooting past the set point. Additionally the temperature is much more consistent, because the element only turns on a little bit of smaller temperature drops, and heats more vigorously for larger temperature drops.

Boiler Style

Different machine utilize different styles of boilers for steaming. Boiler size is often determined by the available space within the machine. Smaller home units, such as semi-automatics and super-automatics have very limit internal space, which require smaller volume boilers.

Tub/Small Volume

Small volume boilers frequently heat for both the brew and steam functions, or two separate small boilers are used for each function. This type of boiler is typically used on semi-automatic machines because of their limited internal space. Small volume boilers are controlled by simple thermostats that turn the boiler on or off. These boilers typically only heat brew water within the 150-180 °F temperature range. Since they are only heating a small volume of water they do heat fairly quickly, but depending on their size, they may limit the size of the drink that can be made.

Heat Exchange

Heat exchange boilers are frequently used in higher end equipment and commercial machines. As a result longer shots can be pulled from them, and need little to no recovery time between drinks. Heat exchange boilers are typically controlled by a pressurestat, which allows for the steam pressure to be adjusted lower or higher based on user preference. Pressurestat systems usually have less variance than thermostat controlled boilers as well. Some heat exchange machines will control the steam boiler through a PID unit which is set to an exact temperature. As a result the brew temperature is kept very consistent.

Twin/Dual Boiler

Twin and Dual boilers systems are advantageous for several reasons. The main reason is that there is an entire boiler dedicated to the steam and hot water functions specifically, while another boiler handles the coffee. This reduces recovery times. Additionally on single heat exchange machines the brew and steam temperatures are interrelated, because the set steam pressure determines the resulting brew temperature. One dual boilers systems the brew and steam temperatures are controlled separately. Many dual boiler systems allows the service (steam) boiler to be shut off completely, which saves energy if you don't plan on frothing.

Cup Warmer

For espresso extraction temperature consistency helps produce a better tasting shot. In order to achieve this it is favorable to have as little temperature loss from boiler to cup. One feature that many machines include is a cup warmer.

Cup warms are heated passively or actively. Passive cup warmers simply utilize the passive heat from the boilers to pre-heat the cups. This style of cup warmer is much more effective on prosumer and commercial style units because they have much larger boilers. The large boilers produce a lot of extra heat, which is captured by the metal casing of the machine. Cup warmers can also be actively heated. Actively heated warmers use a small heating element or thermal pad to heat the cup warming tray. For safety reasons these warmers do not get very hot - generally these will only heat slightly above room temperature. On units with smaller boilers an active cup warmer is more effective than a passive system.

Cup warmers are also available as a separate accessory. One example is the Jura-Capresso cup warmer showcased in this video here.

Steam Features

These features pertain to the steam and hot water functionality of the machine.

Wand Style

Different wand styles affect how the user can interact with the wand during frothing. Some basic things to consider are the wand length, how the wand is angled, and how much space there is for the pitcher to fit beneath the wand. Certain machines are also meant to be used with a special frothing attachment, such as a pannarello. User convenient machines may not include a wand at all, but instead will use an automatic frothing carafe.

Wands are generally adjustable in three different ways. Pivoting wands simply swing from side to side. Rotating wands can are able to turn in place, but don't have any vertical motion component. Articulating wands will both swing and rotate, making this wand style much easier to position. High end home units and commercial machines will typically use an articulating style wand because of the easier control.

Most wands use a rubber or silicone grip to grasp for adjustment. If a wand is described as being no burn style, it means the wand has an internal insulating tube. This tube contains most of the steam so that it is not in direct contact with the metal tubing of the wand. This does not mean that the wand does not get hot. These wands simply take a longer time before they get hot, and they cool off much faster than a traditional steam wand.

Pressure/Temp Control

Semi-automatic and super-automatic home units will not typically have any steam pressure control. They have set thermostats that only heat to a certain point, so steam pressure is limited to this one setting. For super-automatic machines that use auto-frothing carafes or nozzles they may list a temperature setting within the machine's programming. This simply froths the milk for longer, this does not control how much pressure is built up in the boiler.

Higher end semi-automatics, prosumers, and commercial units are typically going to have a way of controlling steam pressure. This is achieved through a steam pressurestat, or a PID. A steam pressurestat is an adjustable steam pressure control. This can be used to lower or raise the pressure of the boiler. Raising the pressure increases the volume of built up steam in the boiler, which will in turn provide a drier more powerful froth. Most home units will have a limit of 1.2 bar steam pressure before their safety releases begin venting steam. Commercial units can get well past this because the are built to safely handle higher steam pressures. The amount of variance in the steam pressure will depend on the quality of the thermostat - higher quality pressurestats will provide a more stable steam pressure.

Other machines will control steam boiler pressure through a PID which sets the exact temperature of the boiler. This provide an even tighter variance than a pressurestat, because the PID very quickly detects temperature changes and properly adjusts for them. PIDs are easier to set as well, since they can usually be adjusted externally, whereas pressurestats are usually located within the machine.

Boiler Style

Different machines utilize different styles of boilers for steaming. Boiler size is often determined by the available space within the machine. Smaller home units, such as semi-automatics and super-automatics have very limit internal space, which require smaller volume boilers.

Tub/Small Volume

Small volume boilers frequently heat for both the brew and steam functions, or two separate small boilers are used for each function. This type of boiler is typically used on semi-automatic machines because of their limited internal space. Small volume boilers are controlled by simple thermostats that turn the boiler on or off. Because of their small volume these boilers typically won't have a very high steam pressure and can only make a fairly limited amount of steam because of the size of the boiler. There is also a larger variance in the steam pressure because the thermostat uses a simple on/off function. These boilers will not be good for frothing lattes back to back because of the required recovery time.

Rapid Steam/Thermo Block

Rapid Steam and Thermo Block boilers both operate by passing water through a small channel which is surrounded by metal that is heated to a very high temperature by a heating element. This is advantageous because the steam function of the machine heats very rapidly, making shorter recovery times. Because this is not a true boiler the steam pressure will be limited since only a small amount of water is heated at a time.

Heat Exchange

Heat exchange boilers are frequently used in higher end equipment and commercial machines. They are usually large volume boilers, which means there is a greater head of steam that is formed. This means the steam comes out of the wand with more force, and the steam will last longer. This type of system requires less recovery time. Machines that utilize these boilers need little to no recovery time between drinks. Heat exchange boilers are typically controlled by a pressurestat, which allows for the steam pressure to be adjusted lower or higher based on user preference. Pressurestat systems usually have less variance than thermostat controlled boilers as well. Some heat exchange machines will control the steam boiler through a PID unit which is set to an exact temperature. As a result the steam pressure and temperature is kept very consistent and has the least variance.

Twin/Dual Boiler

Twin and Dual boilers systems are advantageous for several reasons. The main reason is that there is an entire boiler dedicated to the steam and hot water functions specifically, while another boiler handles the coffee. This reduces recovery times. Additionally on single heat exchange machines the brew and steam temperatures are interrelated, because the set steam pressure determines the resulting brew temperature. One dual boilers systems the brew and steam temperatures are controlled separately. Many dual boilers systems allows the service (steam) boiler to be shut off completely, which saves energy if you don't plan on frothing.


Steam Tips

Automatic Frothing

Types of Machines

Manual

Semi-Automatic

Super-Automatic

Prosumer