IMS vs VST Basket Review: Espresso Baskets and Their Impact on Extraction

Espresso baskets: they are small yet essential. Even though they play a leading role in espresso extraction, their influence is often overlooked.

In fact, about six years ago, Vince Fedele, the father of the VST basket, first introduced VST to the coffee world, long after other specialty coffee equipment like multi-boiler systems for espresso machines. Over the past few years, attitudes toward espresso baskets have continued to evolve.

Today, a new challenger has emerged in the world of baskets—IMS. In the battle between IMS and VST, who will emerge as the ultimate champion? Next, we'll compare them through a series of blind tests.

In the Basket World, Who Are You?

When VST revolutionized the scene, they were not the first to tinker with "baskets compatible with espresso machines." For example, Synesso baskets have been highly rated. That said, VST was the one that conducted the most comprehensive research on factors like "particle size impact," "hole size," "shape of the coffee bed during extraction," and whether the basket's holes and shape could completely filter the coffee.

Before this, most baskets had significant design flaws. The hole size was extremely varied, with some large enough for coffee grounds to pass through and others so small that they clogged the basket's bottom holes.

Moreover, the shape of these baskets often failed to meet extraction needs, as the outlet surface area was smaller than the inlet, leading to suboptimal water flow through the basket.

Seizing this opportunity, VST baskets quickly claimed a dominant position due to their consistent quality over the years. Some baristas might complain about certain shortcomings of VST, but most minor issues can be resolved with better distribution and tamping.

Nevertheless, a new brand in the basket world has gradually come into view—IMS. This Italian company has been manufacturing metal components related to espresso machines since after World War II. They have now released a new basket called "Competition Filters" to compete with VST, claiming to offer similar advantages.

With that said, it's time to put them to the test!

VST VS IMS: Extraction Method

We conducted blind tests using a series of coffee beans through espresso extraction methods, including lightly roasted and well-developed beans from Rwanda and Tanzania.

We used the EK43 grinder and the Kees Mirage semi-automatic espresso machine (which can limit water flow and pressure). The extraction amount was slightly adjusted according to each type of coffee bean to maintain overall consistency.

Another parameter to pay special attention to is grind size. We all know that when switching baskets, grind size needs to be adjusted. The issue is clear: larger basket space can accommodate more coffee grounds, slowing down extraction if other variables remain unchanged; however, different basket bottom hole sizes theoretically offset this difference. In fact, when grinding with the EK43, the grind size for a 15g basket needs to be one notch finer than that for an 18g basket to ensure the same extraction amount within the same extraction time.

Interestingly, when comparing VST and IMS, we found that "grind size" is not interchangeable either. IMS requires coffee grounds that are 1-1.5 notches finer than VST to achieve the same extraction results. We suspect this may be due to differences in the basket bottom hole sizes, but we are unable to measure them, so this remains speculative.

Tasting: Our Test Results

In terms of flavor, people generally preferred IMS. Espresso extracted with IMS had better sweetness and delicate flavors. It must be said that the difference is very subtle and would be hard to detect in milk-based coffee.

One possible reason for this result is that to achieve the same coffee amount, extraction time, and extraction volume, the coffee grounds used for IMS are finer than those for VST. Overall, the coffee grounds are more uniform, and the two peaks of particle distribution are closer, resulting in a smoother and fuller flavor. Of course, this remains hypothetical.

However, there is a problem with IMS baskets: when we wanted to use extremely light coffee beans and the smallest IMS basket (15g) for a perfect combination, the EK43 reached its limit. Even with the finest grind setting on the EK43, it couldn't produce a fine enough grind for extraction. Of course, this isn't an issue for most espresso grinders, but if you plan to test with a regular EK43 without the "Turkish grind" option, keep this in mind.

IMS also produces "Single" baskets designed specifically for single spout group heads, aiming to use the same grind size as when extracting with double spout group heads. In practice, at least in our tasting, the coffee grounds needed to be slightly coarser to achieve the same flow rate as a double spout. However, in terms of performance, a single espresso made with a single spout seems to be better than a single espresso split from a double spout extraction.

VST VS IMS: The Final Champion

Based on our blind tests (admittedly limited), IMS holds a slight advantage over VST. The differences between them are very small, much smaller than what their respective manufacturers claim, and significantly smaller compared to some baskets that come with espresso machines.

So, which one is better? Ultimately, it depends on personal preference and how well the basket matches different coffee equipment.

Whether it's VST or IMS, the exciting thing is that more high-quality basket manufacturers are entering the coffee market. This will spark more innovation and improvement.