Portafilter Baskets - Will They Improve Your Espresso?

Should I Upgrade My Espresso Baskets?

Espresso (also known as portafilter baskets) baskets’ vital role in coffee extraction is so often overlooked.  If you own a coffee machine, it’s likely you’ve been content to use the basket supplied with it.  If you have problems with your espresso extraction and flavor, the basket is probably way down your list of considerations when troubleshooting.  But, when you really think about it, of course, the basket has an enormous impact on your finished coffee.

Espresso baskets change the flow of water through the ground coffee.  The holes, and their shape, size, and consistency provide a portion of the resistance which is crucial to good espresso extraction, so if your coffee baskets are of poor quality, your finished coffee may be too.

The espresso basket is such a forgettable little piece of your machine, it’s easy to underestimate just how important it is but coffee expert James Hoffman says a precision engineered basket is an essential upgrade. So let’s take a closer look at just how they can impact your espresso.

Types of Espresso Baskets: Pressurized vs. Unpressurized

The first thing we want to address on the subject of espresso baskets is the pressurized vs unpressurized. So, what’s the difference? And which one is better for making coffee?

A standard espresso basket has a single wall bottom with numerous tiny holes in the bottom for the extracted coffee to come through.  A pressurized basket is double, and has either a single hole, or a concentrated area of holes in the centre for the coffee to come out. The double wall is designed to increase the pressure as it passes through the coffee bed and also to produce a consistent extraction.

Pressurized baskets can be useful for people wanting to use pre-ground coffee of unspecified coarseness in their espresso machine. This is because the artificially generated pressure can increase extraction time on coffee which is too coarse to make a decent espresso. 

There is no real benefit to the flavor or aroma of the coffee, but the crema will give the visual illusion of a well-extracted coffee.  Put simply, pressurized baskets are good for people who do not have a grinder at home, are on a low budget or do not know how to calibrate a grinder.

Our advice is to steer clear of pressurized baskets and instead choose fresh, good quality coffee and invest some time in learning barista skills.  Take a look at our blog for lots of articles on how to make espresso, understand coffee extraction, and tamp correctly. All these things will improve your espresso and negate the need for pressurized baskets.

Basket Shape

To understand better espresso baskets, we need to consider how specific design aspects such as the configuration of sides (straight, ridged, or tapered) alongside the hole size distribution influence the extraction quality, and the ultimate taste of the coffee.

Ridged vs Ridgeless

Ultimately, the reason some espresso baskets have ridged sides, is to hold the basket more securely into the portafilter.  This is to prevent the basket popping out every time you knock your puck out.  However, most good quality portafilters are fitted with a ‘spring’ which is a thin strip of metal around the edge which should hold in the basket adequately.

Basket Shape

Some baskets, especially single shot baskets, will be tapered. Meaning the sides slope inward towards the bottom of the basket. This type of basket reduces the surface area of the hole at the bottom and is way of increasing the resistance provided by the basket.

By tapering the sides inwards, the water which hits the coffee on the outer edges, has further to travel, towards the centre, to exit the basket. Straight sides are recommended as they make it easier for the whole coffee bed to experience the same flow-rate, giving a more reliable result and more even extraction.

Hole Size and Distribution

While it may not look like it to the naked eye, standard baskets’ holes are inconsistent; with blurred and jagged edges, and holes not properly punched through. All of these things will create inconsistencies in coffee extraction and flow quality. It is clear under testing that precision-engineered baskets are a game-changer for the extraction of espresso.

Utilizing image different processing techniques to analyze espresso baskets, this study examined hole diameter and distribution. The findings highlighted significant variances across different portafilter baskets with VST filters emerging as the winner due to their precise hole size variance.

Uniform hole size is important in espresso baskets since it determines the way water will flow across the coffee. If there are many holes in an area that are smaller or blocked, espresso will not flow in that area and lead to under extraction.

New Basket Technology

Take a look at espresso baskets under a microscope and you will suddenly understand why coffee professionals are so excited about precision-machined baskets.

Baskets which have been CNC machined are precisely made, the hole pattern is consistent, their edges are clean and smooth.  Micro-cutting the holes like this, rather than punching them through means that the hole-pattern can stretch much closer to the outer edge of the basket, evenly extracting the coffee there, rather than channelling it into the centre.

Precision machining also means you can alter the shape and size of the holes. This is crucial for making different sized baskets for different amounts of coffee, allowing the resistance offered by the basket to be proportional to the amount of coffee being used.

Basket Sizing

Now that you’re convinced on upgrading to a precision-made espresso basket; how do you choose the right size for you?

Selecting the correct diameter of basket is easy – that will link directly to the size of the portafilter (and group head) on your coffee machine.  The next decision is based on how much coffee you want the basket to hold.

A double espresso can be extracted from between 14-24g of coffee – that’s a vast difference if you’re going to use the same sized basket. Which is why IMS and VST manufacture baskets to accommodate different amounts of coffee; ensuring that the depth of the basket, the hole pattern and sizing, and the resistance are all perfectly calculated to extract the given amount of coffee. This way, you don't have to change your grind size between filter if you wish to have left coffee.

If you try to brew your espresso in a basket that’s too small; the coffee will overwhelm the basket, and likely touch the shower screen during extraction. The result will be a slow shot time but under extracted coffee which you will need to grind coarser to compensate for, meaning and even more under extracted coffee. 

Choose a basket that is too big, and you will likely find the puck is swamped with water at the end of brewing, as there is excess space for it to sit on the top of the coffee bed.  This scenario, whilst messy and difficult to knock out, is less likely to impact the flavour of your espresso. For this reason, if you are torn between two sizes, we advise you to size up rather than down.

Takeaway

You will get a better flow quality and more even extraction if:

• The sides of the basket are straight up and down.
• The hole-distribution is evenly spaced and right to the edges of the basket.
• The holes are precision-machined with clean edges and no inconsistencies.
• Your basket is the right size for the coffee you put in it.

All around, the above factors create better quality flow, more even and more consistent extraction.  They also, according to James Hoffman, result in ‘sweeter, more complex espresso’ with more reliable results.

Making the Right Choice

It is clear under testing that precision-engineered baskets are a game-changer for the extraction of espresso.

If you are taking the time to dial in your coffee, measure you input and output, pay attention to the flavour of your espresso; it’s clear that quality and consistency matter to you so an upgrade to your espresso basket seems like a logical step in achieving greater control over your espresso outcomes.

Baskets with straight sides, clean lines, and tighter hole size distribution result in greater extraction of espresso.  They are also much more predictable than standard espresso baskets which is one less variable to worry about when trying to make the perfect espresso.

Now that you know which key features to look for, browse our collection of VST and IMS espresso baskets to choose this essential upgrade for your coffee machine.