A few thoughts about why you should jump on board and at least try the VST Precision filters, developed with La Marzocco.

First of all, as with all innovations i expect there will be a few detractors who will claim the filter basket manufacturing makes no difference to the flavour in the cup. They will probably task anyone to be able to tell the difference. Well, i will hold judgement on that one until the VST baskets arrive, but the fact that many well respected espresso professionals have already tested them and claim they are seeing an improvement in consistency, is enough of a reason for me. If La Marzocco deem them to be an improvement then i think that is enough for us to all sit up and take notice. Will they make espresso coffee taste better? If so, i believe they will do it through increased consistency more than anything else. Consistency across the filter during an extraction and consistency across multiple VST filters.

Have you ever noticed that some holes in your existing filter baskets get blocked by fines, while other remain clear? And that different baskets of same type extract at different speeds? That could be due to the variance in hole size. VST and La Marzocco have set about to change that, creating a basket which extracts more evenly across the bottom surface area of the filter, with much less tolerance built into the manufacturing process for holes size and shape variance.

These filters have a flatter bottom than some, and flat sides. This should be a good thing, but you may have to adjust your tamping technique slightly if you have been used to using a basket with curved sides. More on that once they arrive.

At 25 bucks a basket, not including shipping, it doesn't make sense not to use (or at least test) something that could eliminate one of the many variables involved in the espresso brew recipe!

Since each VST filter basket is trackable via a 2D code printed on the side, and each VST basket is measured and has its own unique profile recorded (presumably somewhere at VST?) there is also potential for baristas to compare baskets to some degree. Although, given the now much smaller variance in basket manufacture, these baskets should prove to be a lot more consistent, both shot to shot and when comparing two VST baskets.

Secondly, these VST Precision filter baskets should fit any standard portafilter, so that includes e-61 machines owned by coffee hobbyists such as myself. You might need a naked portafilter to fit the triple 22g mother VST basket, but i can't be sure on that until it arrives in the post. Expected delivery is currently forecast for beginning of May.  I will be testing the 18g and the 22g VST basket.

The list of features according to the VST filter basket brochure include:

• New Micro-Machining Fabrication Process Consistent Uniform Extraction
• Reduced Sediment Warranted Zero Defects
• Filters Matched To Ensure Identical Performance
• Every Hole Measured On Every Filter
• Each Filter Marked With Unique 2D Reference Code
• Improved Structural Integrity Available in 3 Sizes

Update 17/7/2011: You can now buy VST filter baskets in Australia direct from Ministry Grounds web store.

Buy VST filter baskets in Australia ...

Just a quick update to show this lovely roast of three different cup of excellence winning lots from the 2010 Nicaragua competition. Since samples are only about 150 - 200g each i've combined three different samples here:

• Lot #12 Los Jilgueros (cup of excellence jury score 87.50)
• Lot #16 El Recuerdo (cup of excellence jury score 87.00)
• Lot #21 Santa Gema (cup of excellence jury score 86.67)

Weight of roast was 530g all up. FC at 11:50, dumped at 15:00 at 213 degrees (well before second crack).

Can't remember a three-bean blend coming up this even for a long time. Smells sweet. Looks like one of these was a pacamara variety.

Home roasters take note, you can get these bag sealers on ebay for about 50 bucks delivered. Mine has lasted me over a year now and they come with a spare element. Definitely a must have!

It's not often you hear of, or have the opportunity to taste a coffee which rates higher than 95 points. Much less one which is rated a whopping 99 points by a respected roaster/importer/expert in the specialty coffee industry.  Thanks to a stroke of luck in a spur of the moment giveaway on Twitter, @Hasbeanroaster was kind enough to send me a sample of the very special Bolivian coffee from the Machacamarca de Berengula farm.  This is a world farm exclusive coffee which to my understanding means that HasBean have sourced, imported and are probably the only ones distributing this coffee to a lucky few customers. 

The other Bolivian coffee i sourced recently is Cafe Familia Montano via Ministry Grounds. Interestingly the tasting notes for these two coffees are remarkably similar!

• Grape acidity
• Pronounced sweetness / super sweet
• Caramel & toffee

Hmm, I wonder how the two will compare! I'm yet to roast any of the Montano, so the comparison will come later, but for now, let's look at the Machacamarca from Has Bean:

Roasted on the 1st of April, thanks to a slight hold up in Australian customs i've received it today, the 18th. Not ideal but definitely still fresh enough!  My wife and I will get through it in a couple days, i'm sure.

The roast depth and development on this coffee is absolutely beautiful. As an amateur roaster, i spent quite some time analysing the beans and just trying to imagine what kind of roast profile was used. It's a light espresso roast, about the same roast depth as i normally aim for - retaining all that varietal/origin character and yet it is not lacking in roast development or flavour.  Just how I like it.

Update: Roast time is approx 13 mins and drawn out from first to second crack.

Part of the reason i roast at home, is because i prefer a lighter roast than many cafes (but not all) offer when you buy their beans.  I think it's great to see Has Bean not afraid to use this kind of roast profile for high quality coffees like this one, which respond so well to a lighter roast.

How did it taste?

First up, as espresso I've tried it with a 19g dosed triple basket into 80mL of milk, and 170mL of milk (unhomogenised Maleny Dairy gold top). Then as a chemex.

I definitely agree with the tasting notes on this one. White grape acidity is a great descriptor, and the sweetness is extremely high and lasting. But at the same time, there is this clean, powerful body in perfect balance. The dry fragrance alone is quite astounding.

My own tasting descriptors would be similar:

• Refined acidity in balance with a clean, powerful body
• Extremely high, lingering sweetness not unlike a Kenyan but not quite as citrus or sharp but more of a refined acidity (probably helped along by the lighter roast)
• Flavour reminded me of a melted caramel
• The acidity is more like grape juice, not grapefruit

Is it worthy of 99 points? I would say it could very well be yes, simply because it's an extremely sweet coffee that is perfectly balanced and also has unique flavour attributes which i really enjoy. The beautiful roast depth and development on this one make it a 99 point coffee for me.

Huge thanks to Has Bean for sending this one down under, and for the awesome red HasBean towel!

For more info on this amazing coffee or to grab some for yourself check out the HasBean web site.

First roast of this one. Huge pacamara beans from the 2010 Nicarague cup of excellence lot #4. Only a few small defects. I've got two kilos of this to get through, so hope it tastes as good as it looks. Other greens just arrived; Kenya Gethumbwini AB, Kenya Kagunyu AA, and another COE from El Salvador.

Roasted up evenly. I dropped at a pretty high heat, and ended up at first crack at 9:45, pulling the roast at 13:00 for what i would call a light espresso roast depth. Bagged and sealed, we'll see how it tastes in a few days.

Update: Roasted this too light for espresso (too acidic) but tasted great in the chemex. Needs a longer roast around 15 mins.

And the roast log:

I recently pulled my Isomac e61 machine apart to tweak the brew pressure, and figured i would take a photo while i had the case off.

On an e-61 machine with a tank and vibration pump such as this one (as opposed to a bigger and more expensive, plumbed in rotary pump), brew pressure is controlled by the over-pressure valve. Since a vibration pump is powerful enough to exceed 15 bar (and we only want around 9 bar for espresso), the OPV bleeds off pressure in real time, mechanically, while the brew lever is in the up position.

You can set the point at which it bleeds off pressure by simply turning the OPV one way or the other. On my machine, a counter-clockwise quarter turn was enough to reduce the brew pressure to 9 bar (from about 9.7 bar). This has slightly improved the flavour of the coffee - perhaps it is extracting less of the bitters and more of the good stuff. Taste is definitely more rounded. Everyone seems to like the taste of shots at 9bar, so i'm sticking to that for now.

With less brew pressure you also get a slightly slower flow rate, which on an e61 with only a few seconds of pre-infusion, probably helps as you can stretch your shots out that little bit longer and end up with the same weight/volume in the shot. But less pressure also means less "stuff" extracted from the coffee.

The other interesting thing that can be adjusted (although i haven't had to adjust mine) is the pressurestat. This is basically the thing that detects pressure in the boiler, and sends a signal to the control board to tell the element to turn on or off. My pressurestat keeps the boiler between 1.0 and 1.3 bar, which is pretty standard. In a single boiler heat exchanger, that's a happy medium - anything more and you'd need a much longer HX pipe or it'd run too hot, anything less than 1bar and you wouldn't have enough pressure for getting that perfect microfoam.

Machines like the Expobar Minore with dual boilers have the advantage that their steam boiler can simply sit at 1.5bar all the time, giving great steam pressure while the brew boiler sits at just the right pressure to deliver the required brew water temp. 

One disadvantage of dual boilers is your brew water comes from inside a boiler which has an element exposed to the brew water. Unless you filter your water well (think reverse osmosis or ion-exchange resin) that boiler may have scale, which can affect the taste of water. HX brew water comes through the HX pipe from the tank, so there's less opportunity for scaley tasting water getting into your coffee.

The thing i love about e61 machines is, parts are so readily available and can be interchanged easily - i could upgrade my pressurestat to a more expensive brand/model and reduce the deadband if i wanted. Elements can be changed, silicon tubing can be replaced with ease, nothing is proprietary. Everything is pretty solid and although not every e61 is the same, most will pull a very respectable shot.