Rocket Evoluzione Giotto v2 Review, part I

The front panel of the Evoluzione model 

When I first-handed received a Rocket Giotto Evoluzione (first version) for testing, there was no doubt in my mind, that I was up for a Rocket Espresso made espresso machine, when I was economical ready to upgrade the machine park.

This was even more clarified when I received a Rocket Giotto Premium Plus v2 machine (also for testing) – because it simply solved every single task that I put up fore it. You might wonder why this was such a logical purchase for me, without testing any further into the world of espresso machines? I was truly sold into the quality world of Rocket Espresso, where their products are made of the finest steel and greatest craftsmanship. This specific review of the newly purchased Giotto Evoluzione v2 espresso machine from Italian, Rocket Espresso will perhaps spread some of my enthusiasm in your way.

Top of the espresso machine

Design

Firstly I will focus on the design, because I find it extremely relevant when comparing espresso machines, because most of the espresso machines in same price range offers the same technical specs, so its left to the design and the “feeling”, when using the specific machine. This is also my point of view, because you will (if you are a true coffee nerd/enthusiast) use the machine on a regular daily basis and therefore will the design/feeling play a great part of how enjoyable this moment will be. 

Rocket Espresso is providing their machines with such finesse, that its hard to oversee when looking around at the espresso machines options – I mean the edges of the Rocket models isn’t just left rough and sharp, but is instead bended and fitted perfectly when assembled. This applies such a gap between a Rocket espresso machine and other available machines, ex. Izzo – that it definitely should be considered when purchasing your own dream machine.

Likewise is the steel color different from the available machines, because the Rocket machines possesses a goldish steel color versus the general cold steel color, but isn’t this a very small detail? Well, it’s an extremely small detail, but look at it from this angle – you will have to look at your machine every day, because it isn’t place-able in a kitchen closet.

Overall, the Rocket espresso machine models is possessing the greatest outer design, when talking the finish – no doubt about that and also has the greater looks when it comes to the steel used, but.! The Rocket has designed the water outtake a bit too close to the lever and therefore isn’t so operational as I would like it to be – for my personal use this isn’t a deep con, because I´m more into the cappuccino thing than a Americano – but for a Americano fan, this would be a considerable con.

Technical specs

           

            Bodywork                   Steel (AISI 304)

            Brewing head              Commercial brewing head (4.05 KG/ 9lb.)

Pre-infusion                 Dual pre-infusion system: mechanical pre-infusion system with progressively working piston and static pre-infusion chamber. (This reflects a smooth coffee extraction with optimum aroma, body and crema)

Thermo Siphon           Superior layout of thermo siphon design resulting in optimum extraction. With a 20% higher volume than comparable machine on the market, quote Rocket Espresso.

Boiler                          Boiler is made of pure copper (Cu 99,9%) with two lead free, heavy brass end plates. These brass end plates combined with the special additional boiler insulation increases the thermal retention by up to 50% versus other boiler systems, quote Rocket Espresso. (Boiler capacity 1.8 L.)

Pump type                   Full commercial rotary type pump (not vibrational type pump) with external pressure adjustment. 

Pressure control           The machines comes with a full size commercial rated pressure switch (0.35 degrees temperature differential tolerance)

Pressure gauges           One dedicated gauge for pump pressure and one for boiler temperature control.

Steam wand                With our cool-touch technology: anti-burn (only the nozzle gets hot) easy cleaning as milk doesn’t bake on wand; more efficient steam, as heat is not dissipated around the wand. Steam nozzle designed for easy milk foaming with fine texture.

Electronically              Microprocessor controlled automatic level control of boiler and fresh water reservoir, with low water level indication system.

Heating                       Optimized boiler capacity to thermo siphon system ratio. Results in fast heat up time with 1.200W element, made from special long life material. (5 times longer than normal elements)

Safety Valve                Fully certified commercially rated safety valve.

Water Supply              2.9 L fresh water reservoir or alternatively by turning the control switch, steel braided direct water connection (hard plumbed) with full drip tray drainage system.

Dimensions                 (W * D * H) 

                                    Rocket Giotto Evoluzione V2: 33 cm * 42.5 cm * 39 cm. (13.0 in * 16.73 in * 15.36 in)

                                    Rocket Cellini Evoluzione V2: 30 cm * 42.5 cm * 39 cm. (11.8 in * 16.73 in * 15.36 in)

Weight                         27.8 KG / 61.4 LB.

Additionally                Full size commercial one and two cup filter handles and baskets. One blind filter. Metal tamper. Microfiber towel. Group cleaning brush. Full training guide and instructions (CD and manual).

Next part of the review will be posted the 04-08-2012 (DDMMYYYY).


// Hendrup

Difference in Pitchers

Two different pitchers

I have been steaming in about 1,5 years with my steel series pitcher off 0,35 L. pitcher, which until now have been more than enough - but in that period I had never been relatively close to pouring some great latte art. I have always thought and blamed my previous espresso machine, the Francis Francis X1, which definitely had a thing or two to do with it - but never my pitcher.

Unknown 0,35 L. pitcher

This lead me straight to watching online latte art videos and reading endless articles off the dos and don´ts. Therefore I currently upgraded my espresso machine and thought all would be in order and it sort of was, I was producing some great micro foam, but didn't get the pour right. You are thinking which cup are you pouring in, because it does matter if the bottom of the glass/cup is curved or flat - and Im currently using a glass with a flat bottom.

But I was at once chatting my way at the local coffee shop and saw the Motta pitcher, which was a lot heavier than my current pitcher and also had a better designed spout. I was also introduced to the fact that the latte art champion Chris Loukakis always uses this exact pitcher, therefore I had too try it.

Motta 0,35 L. pitcher

To be absolutely precise the weight difference between the two pitchers is 77 gr., which when you are holding the pitcher fells like a lot. The steel series pitcher weighs 137 gr. and the Motta pitcher weighs 214 gr. - both off them is a 0,35 L. pitcher.

Did it help me out regarding to the latte art problems? Well actually the milk was a bit more easy to steam in the Motta pitcher than the unknown pitcher, because it is formed more cone like. More importantly the spout makes a huge difference, when talking latte art - you have more control upon the milk flow and can actually draw upon the foam surface, where the unknown pitcher just dumps the milk. But a true con and the only to the Motta pitcher, is that its more heat resistant - meaning that the sides of metal is a lot thicker and therefore takes more time to adjust to the milk temperature inside. So if you are using the side of the pitcher to get a hold off how the temperature is rising, then you will be better off with the unknown pitcher.


// Hendrup

VST Baskets, introdution

VST Precision Competition Filter Boxes

Veteran Italian espresso machine manufacturer La Marzocco teame up with VST, designers of the popular ExtractMoJo device to produce a more accurate, more consistent way of extracting espresso shots. When put under the microscope (or even looking with your naked eye) espresso filter baskets are manufactured such that the holes vary not only in size, but also in shape.

VST Precision Competition Filter 20 gr. Filter Box

VST filter baskets are manufactured with much lower tolerances, such that each and every hole is measured on every filter to ensure that they are all within a diameter limit of +/- 30 µm. That is, 30 microns, where a micron is 1/1000 of a millimeter. All VST filter basket holes are measured for a number of different parameters to ensure consistency, including circularity, area, placement and also checked that no holes are completely blocked. As you can imagine, the manufacturing process involved in the development of the VST filter took some time. Each VST filter is warranted for zero defects. 

Included documentation in the two boxes

The VST filter also has much straighter sides top to bottom than some other brands, and the holes run closer to the edge of the filter. They are designed this way to ensure the water travels the same distance on the edge of the filter as it does in the middle, aiding in achieving consistent espresso extraction across the coffee puck.

VST filters allow for better consistency and this also means poor technique such as uneven tamping will show through in the shot. And so the VST becomes not only great for achieving better espresso day-to-day, but also for training purposes. Just as the naked portafilter allowed the Barista to see the extraction, the VST filter helps the Barista to further improve tamp and dosing technique.

The different VST baskets from varies angles

There are obvious caveats here - your technique must be reasonably good. You don't need to be a world Barista champion to get a lot out of the VST baskets, but you do need to tamp evenly and dose consistently, as with any espresso basket - perhaps more so with the VST.

You may find you need to grind a little finer than with other baskets, since there are more holes. In general, many respected coffee professionals agree that espresso extracted will through the VST baskets tastes better. Some say it brings out more distinct flavors in the coffee. Extractions tend to be consistent not only shot to shot, but between different VST baskets, since they are all virtually identical.

Espresso shot using the 20 gr. VST Basket

Since VST baskets are still relatively new, you may still be using the portafilter basket which came with your espresso machine and thats okay - but if you wanted to try something new which could noticeably improve the taste and consistency of your espresso coffee at home, then VST baskets are worth a shot. 

Comparison between a standard and a VST basket

Trying to decide which size you should buy? VST filters should fit into most standard 58mm naked portafilters, while 15gr. and 18 gr. should fit most spouted portafilters. If deciding between the three VST basket sizes (15 gr., 18 gr., 20 gr. and 22 gr.), its helpful to know how mush coffee you currently dose into your existing basket. If you have digital scales, weigh your standard dose. Most double baskets fit at least 18 gr. of coffee, while a triple can fit 22 gr. or more. With this in mind, choosing between the VST filter basket sizes is relatively straight forward. The 18 gr. VST seems to be the most popular size, and is great for a single shot of good strength. 

According to VST, the 18 gr. basket is 24.2 mm high, while the 22 gr. basket is 28 mm high. If you use a spouted portafilter, be sure to measure your existing basket so you have some idea of which size VST will fit. Obviously, all three sizes should fit in most naked portafilters.

// Hendrup

New Coffee Area

A close up view at the current set-up

Maybe you have been surfing some of my articles before and noticed that my pictures have quite a good view, due to the placement of my home on fifth floor. Well, I have moved into some new facilities and therefore has Coffee Channel moved along with me - which will provide some new angles and backgrounds on the pictures, as you may spot.

This is my visible set-up, there´s a lot more in the closet :)

The moving is a step in my personal life, because Im going on the school bench once more and therefore needed to find something a bit more suiting for a student - the way I see it, there will become a greater amount of money to spend on coffee gear.

I really want too ensure the followers that this moving isn't a drop in quality on the Coffee Channels behalf, because there will be more room for testing, but maybe a drop in creating such beautiful pictures, due to my new apartment on third floor - but I will try my best.!

// Hendrup

Beer, Cold Brewed Coffee

Espresso stout from my local coffee shop, Kaffemekka

Intro
I have purchased this special beer from my local coffee shop, KaffeMekka, where it was price labeled at 45 DKK ($7,5) - which is in the higher price end for special beers, normally from 30-40 DKK ($5-6,5). The back label states;

"You should look forward off tasting this mild and rich stout, with cold water extracted high quality espresso coffee. The beer holds a fine coffee flavor, which complements the roasted malts and the discrete hop aroma. The Espresso stout is an experience in its own way, but its highly suitable along with chocolate and strong desserts. 

The Espresso Stout is a result of a unique cooperation between the recognized brewmaster Anders Kissmeyer from Søggards Brewery and the coffee shop, KaffeeMekka.

We hope that you will enjoy this Espresso Stout as much as we enjoyed brewing it." 

The backside label of the Espresso Stout

The special beer holds 0,5 L. of liquid which at 7% alcohol, leaving this bottle of being 2,8 drinks and contains barley malt, honey, muscovado sugar, coffee extract, oats and hops.

Taste describtion
The smell of this particular beer is partly sweet stout (malt) but also a bit caramel, telling your mind into thinking that this beer is indeed very sweet - and it is. The beer has an incredible round and full body, where its a mixture of lightness and sweetness, which is highly enjoyable. The taste is at first a bit strong, and then fades into an aftertaste where notes of coffee and chocolate, caramel is localized.

This beer is highly drinkable, but a bit too dark to enjoy standing alone - so if you are able to get your hands upon one of these brews - add some snacks while drinking.

// Hendrup

A Beginners Milk Frothing Guide

Microfoam, which hasn't been stirred yet. 

Intro

You have might been trying to steamed some proper micro foam - maybe you had success otherwise you hadn't, therefore lets look at the guidelines. There is always room for improvement and I often look through different guides to pick up an extra tip or trick and thereby becoming a better home-barista.

Micro foam takes a lot of steam capacity from your espresso machine and especially when making the larger latte drinks - therefore the minimum steam boiler capacity of a HX-machine would be around 1.0 L. and 0,75 L. for dual boiler. You might be wondering what difference does it make, but actually there is a great difference, because with a larger boiler the steam will exit consistently and endless compared to a small boiler, where it will come in stages.

The reason for the steam stages is because the boiler always needs to have some water covering the heating element otherwise it will burn out; Francis Francis X1 has a 325 ml. boiler, where some of that volume always needs to be water, therefore you are left with 200 ml. steam at max, which isn't the grand thing when steaming for two cappuccinos in a 0,75 L. pitcher. In other words the steam pressure will dry out many times before you are finished producing the micro foam and the micro foam will also suffer badly under the inconsistency of the steam.

Bottom line; we can't change your home espresso machine in a heart beat, so lets get on with the guide and hope for the best experience on your home front.

Steamed milk with a two hole tip 

Preparing for steaming

We have rounded topics like your espresso machine and boiler capacity, but these aren't the only things that can get you a little closer towards the velvety micro foam. I have the believe that the steam tip is an essential part of your ability of creating beautiful foam. In fact the steam tip often sets the bar off how well you will be able to steam your milk - you can have a lot of steam capacity and a perfect pitcher, but without a decent steam tip you will be chasing ghosts in creating velvety foam. You will always be able to foam the milk, but the texture of the milk will be awful lacking - I strongly suggest a "professional" four hole steam tip, because this will create four different whirlpool zones and therefore be better to incorporate air into the milk. Be aware that some espresso machines can't keep the steam pressure up for the four hole tip, so hear your local coffee shop before you start investing in gear.

With that said Im in the strongest belief, that a proper Barista can create micro foam under any circumstances, so technique, technique and technique mixed with a little bit of luck.

Pouring the thick and rich milk 

Steaming

Start off be gathering all your equipment, meaning steam pitcher, milk, espresso machine and cloth for cleaning afterwards. Before you begin to steam, start off with a clean cold pitcher and cold fresh milk - never try to re-steam already steamed milk! In other words the colder the pitcher and milk is, the longer you will have to play with it and foam the milk. If you start off with room temperature milk and pitcher, your foaming time will be cut down considerably. Don't make it any tougher than it already is - clean cold pitcher and cold fresh milk.

I

Clean out your steam wand to get rid of any excess water that has condensed up inside the wand - we certainly don't want that going into our milk. Most likely, your prosumer machine will have a heat exchanger system (HX) or a dual boiler, which means your machine is ready to produce steam as soon as its turned on and heated up. If your machine is a single boiler/dual boiler, you have to warm up the machine to steam production by pressing/flipping the steam switch. Wand dried of all moisture build up inside? Great machine ready to go.

II

Sink the tip of the steam wand deep into the milk and open up the wand all the way. Ensure that the wand is fully opened, because sometimes the valve doesn't get open all the way and nervous first timers are trying to steam milk with just a little gurgle of steam coming out of the wand.

III

Steaming, steaming, steaming - you are on the way. Bring the tip quickly and expertly up to just below the surface of the milk so that you hear a ch-ch-ch sound. This is the point at which the milk is being foamed; its commonly known as the sweet spot. If you don't hear any sound, you are not foaming the milk, but instead simply heating it - if you get some big, big bobbles the tip is too high and needs to be lowered deeper into the milk. Until this step everything is coming around nice and smooth, but when surfing the surface, the expertise is dividing the amateur and expert. If you are fulling around trying to find the sweet spot the milk will be heating up and you will be quickly cutting down the time, which you had to create the greatest volume of foam within the milk. You really want to find the sweet spot as quick as possible and thereby incorporate as much foam as you will need.

IIII

When you think you have achieved to incorporate enough air into the milk, simply sink the tip deep into the milk to continue heating the milk up to the desired temperature. NOTE: We are trying to incorporate a lot of air into the milk, but too much foam can actually destroy your pouring latte art. Starting to create foam right after the drop, you should be able to create as much foam as you will need for a latte by about 38-48 degrees (100-120 Fahrenheit) - 60 degrees for a cappuccino (140 Fahrenheit), after which you will sink the steam wand and finish heating up the milk to the desired temperature.


Good luck!

Visiting Italy - the heart of espresso

The future blog articles publishing dates

Im going away on a 14 days vacation in the Venice region in Italy and have therefore prepared some future articles, so you won't be bored while Im gone. The future publishing dates can be spotted in the above picture, where a new article will be released every third day. 

I hope to pick up some new interesting stories, products or great coffees from Italy - which you hopefully will experience after my return. 

// Hendrup

Milk for steaming

Choosen the specific milk for frothing can be quite a challenge

I have the opinion that any Barista or Home-enthusiast most know in specific what groceries they are handling, for example to produce velvety micro foam. Therefore lets get the basics set by clearing out the different content, that milk is combined off - in other words lets get to know milk a little bit better.

In the pursuit of steaming professional micro foam there must be three thing in the milk, that we should have great focus on; fat, protein and milk sugar (lactose). Therefore we can trace this back all the way to which cow the milk is coming from? whats its mostly eating? How all it is? These among others will potentially influence the flavor within the milk and therefore also the final result off your micro foam - but don't go running around blaming the cow because you aren't producing optimal micro foam.

Lactose
When you are tasting the milk or your final cappuccino result - the slightly sweetness and pleasant taste you will experience in the milk is primarily due to the relationship of lactose and chloride contents. Therefore it gives great meaning that lactose is the milk sugar - like mentioned above. The lactose - when steaming the milk and thereby also heating the milk - will begin to dissolve and in turn increase the perceived sweetness, which is what we truly want.

Fats
Milk is solid based in the quality of fat it contains and can range from 0,1% in non-fat to approximately 3,5% in whole milk. Lactose described above gives the milk a lot of sweetness and the fats doesn't provide any taste to the milk, but instead gives body to the flavor - a fuller flavor. Therefore can fat play a big part when tasting the steamed milk, regarding the mouthfeel and texture. The milk fat is therefore providing some get richness to the milk based beverage, that cannot be denied.

Proteins
The most important when seeking the ultimate steamed milk is the proteins within the milk, because they are responsible for our milk being able to be foamed. Understanding how proteins play a part in this matter can be a little tricky or quite a challenge, therefore the following quote.

"Foam foramtion is mainly based on the effect that in the boundary layers of the phases, liquid and air molecules are enriched due to a boundary layer activity and therefore stabilize the boundary layers." Quote Spreer & Dekker

When you are steaming milk you are incorporating air into the milk, the proteins are hereby important because they are being absorbed by a thin film surrounding an air bobble giving stability to the entrapped air. If you are way off track here, maybe read this previous written article; Variables when frothing milk.

When you get the above - you will understand that we want proteins in our milk - but there are actually two types of foam caused by either proteins or phospholipid-protein, so does this matter? Well the relationship of fat and protein can impact how easily the milk will foam and at what temperatures milk is most receptive to incorporate air, so yes. But its an extreme technical point of view when trying to steam milk on home bases, so I will leave it as a cliffhanger.

Bottom line
Non-fat milk is more receivable of incorporating air at low temperatures, this applies also to whole milk although to a lesser extent. Therefore will the milk from fridge temperature and to approximately 38 degrees (100 Fahrenheit), things are looking great for the optimum steamed milk. Nonetheless from 38-72 degrees (100-160 Fahrenheit) the chemical process is reversed with the higher fat dairy products consistently exhibiting a greater volume of foam being produced at any given point.

Most importantly does temperature trumps the influence of the fat on foaming - because all milk regardless of fat content, creates the greatest volume of foam at cooler temperatures.

// Hendrup

Mahlkönig Vario Cleaning

The burrs of the Vario grinder

If you seek excellent ground coffee or just a grinder that will last a bit longer - you might want to clean your grinder. There is a couple of different ways of doing so and because I have a European Vario (Mahlköning), which is the same as the American Vario (Baratza), I will link to some videos, which is describing the right cleaning method.

Seattle Coffee Gear shows us how to clean your Vario using a brush, which is the most cheap way of cleaning your grinder, but does´t remove all excess coffee oils from the grinder and therefore is this method, not the best possible.

Barista Lab shows how to clean your Vario using Urnex Grindz, which is in my opinion the best way to remove all excess coffee oils and grounds - but it will cost a bit more than a brush.

// Hendrup

Rocket Bottomless/Naked Portafilter

The Rocket Bottomless/Naked Portafilter

When I received my newly purchased Rocket Evoluzione v2 espresso machine - I had the pleasure of receiving a bottomless/naked portafilter from Rocket, which gives insight of your tamping technique and the general extraction flow than a normal closed portafilter.

The naked portafilter is a useful tool that has utilization in both café setting and especially for the home enthusiast. In theory a naked portafilter is exactly the same as a normal portafilter handle, with the spouts removed, showing the bottom of the basket that holds the compressed coffee. Having the basket exposed means that you can watch the entire extraction process, and diagnose any problems with the shot extraction. This sounds complicated, but its really not.

Keep in mind that to create a quality espresso or ristretto, you need water to be pushed evenly down through the basket of coffee. If the shot is coming out unevenly its said to be channelling, which can be seen easily with a naked portafilter as the water will pour from the side of the basket rather than brought the middle.

Preheating the Portafilter

I start by running some hot water through the portafilter to ensure that it has been heated properly.

Extraction diagnose:

• A very blond (light) shot may be an indication that you need to dose more coffee in your basket or perhaps your grind is to coarse. 
• A very dark shot is caused by the opposite, dosing to much coffee or grinding your coffee too fine.
• Uneven tamping will cause channelling and thereby leading the water trough the path of least resistance. You will be able to see blonde patches, which indicate where the coffee is not compressed as tightly or where less coffee is distributed.

The color of the shot you pull through the naked portafilter can also be a good indication of whether you are getting it right, a perfect espresso shot should have an even, golden to reddish brown color that starts to blonde (lighten in color) around 25 to 30 seconds in the brewing process.

The steps within the extraction process - see the pictures separately on the CC Facebook site!

The shot shown above reveals an uneven tamp, but great extraction - taking into the blond phase of the shot. This kind of shot will maybe never reveal itself to the common amateur coffee enthusiast, but for those who master the right technique, this shot will be a medal of self-confidence of the highest coffee level. For those whom are not gifted in the art of extracting, a naked/bottomless portafilter is properly the best way to go.

The final brewed shot

From a taste point of view, there are more then a few opinions whether the naked portafilter affects the flavors versus the standard portafilter. In my opinion I have seen an increase of produced crema which also is more airy and therefore makes it more suitable for latte art. The flavors are more cleaner than an extraction that has to run through a portafilter spouts.

Don´t forget that enjoying a cup of coffee is a subjective experience, everyone has a different personal taste and preference, so keep this in mind when you hopefully are experimenting with the naked portafilter.

// Hendrup

Txpresso Steam Knife

Txpresso Foam Knife 1 Hole Steam Tip

Keeping the focus within steam tips used for creating the most delicious velvety micro foam, there has been some small developments within this area of the world of coffee, according to espressoparts.com and coffee hit.com. The newly developed steam tips is instead steam knifes designed to cut the incorporated air bobbles into tiny/micro bobbles, which David Schomer thinks very highly off.

"Steaming with this revolutionary steam tip creates the finest, most silky cappuccino foam I have ever served at Vivace." Quote David Schomer

Im in conflict with my logic about wether this is a better solution than the current steam tip technology already used globally - especially when the focus is cast upon the price level that these two steam tip is introduced by.

• Txpresso foam knife 1 hole steam tip 975 DKK ($162,5)
• Txpresso vortex steam tip 800 DKK ($134)

"We are always looking for processes that will create a better preparation method and higher quality coffee beverages. As a result we have been honored to be a part of many special products related to the furtherance of specialty coffee quality.
The Sproline by SS&W is just one of those projects, however it is also one of the most compelling. 

The work related to these items is that of Shojiro Saito our partner in Japan. Several years ago he created the idea of brewing high quality teas on an espresso machine. While the idea of brewing tea on an espresso machine was not new itself the processes created by Shojiro to create a quality tea beverage were. When introduced to Espressoparts, we asked the question, about coffee and how the system might work. A year later Shojiro responded with what we know call the Sproline of Screens, and steam tips. 

So, what is the process used to create the incredibly tight bubble structure created by these tips? It is called Hydrodynamic cavitation. 

Hydrodynamic Cavitation occurs in liquid when bubbles form and implode in pump systems or around propellers. Pumps put liquid under pressure, but if the pressure of the substance drops or its temperature increases, it begins to vaporize, just like boiling water. Yet in such a small, sensitive system, the bubbles can't escape so they implode this implosion creates what we refer to as nano bubbles. This process as it relates to Tea and coffee milk steaming was recently provided a patent in Japan, to our firm SS&W. 

What is unique about our method is that we have created high and low pressure zones on the output side of the tip. The resulting high and low-pressure zones create Hydrodynamic cavitation and thus an implosion of the smaller micro bubbles created when steaming milk. The bubbles create such a tight bond that the structure creates a glossy surface to the milk that holds shape and pattern for a very long time. The effect of the nano bubble structure also keeps the gas bubbles of the coffee from escaping the surface of the beverage, and damaging the latte art and or foam structure on top of the beverage. 

Independent Coffee Houses and Baristas around the world are just learning of our new methodology, and are blown away by the quality of the milk created by these tips. Espressoparts, is proud to work with not only Shojiro, but all that who continue to look for additional methods that create quality within our industry." Quote Coffeehit.com

Txpresso Vortex Steam Tip

When comparing the price level upon the possibly achieved effect by this new steam tip technology - I must determine that its currently too expensive, considering that its 1/15 off my espresso machines value, which is a lot for only the steam tip!

Hope you checked the attached video above, because its espressoparts.com review of why it should be so expensive.

"The ultimate steam tip. Allows the barista to easily produce perfect micro-foam texture for lattes and other milk based drinks. Simply position the tip in the center of the pitcher during stretching and aerating and submerge the tip in the same position for a whirlpool. The Vortex tip's design creates an automatic whirlpool motion thanks the the positioning and angles of the steam holes." Quote Coffeehit.com

Hopefully it was good reading for you guys, but what do you think about this newly developed technology? Is is just a passing phase or has it come to stay?

// Hendrup

Comparison of Steam Tips

The milk lineup used for the test

I been wondering how different milk types would react, when exposed to the hot steam coming from different holed steam tips - therefore I´d put up a "little" research within the area, where I would examine how easy the combination of a specific steam tip and milk is to froth, but also how long time it will take and finally a summarize of the frothed milk. 

The general idea is to expose the twenty different combinations to one frothing attempt each, where I will judge/comment on that, therefore my skills within frothing is somehow crucial for all of the milks and steam tips try-outs. The single try-out per combination is set, because it will then be a more uneven result and therefore more interesting - in other words I won't give each combinations, many try-outs before I hit the optimal frothed milk possible for each combination.

I listed the different combinations below;

1. Two hole tip - skimmed milk (A - 0,1% fat)
2. Two hole tip - skimmed milk (B - 0,5% fat)
3. Two hole tip - low-fat milk (C - 1,5% fat)
4. Two hole tip - low-fat milk (C - 1,5% fat)
5. Two hole tip - whole milk (E - 3,5% fat) 

6. Three hole tip - skimmed milk (A - 0,1% fat)
7. Three hole tip - skimmed milk (B - 0,5% fat)
8. Three hole tip - low-fat milk (C - 1,5% fat)
9. Three hole tip - low-fat milk (C - 1,5% fat)
10. Three hole tip - whole milk (E - 3,5% fat) 

11. Four hole tip (standard) - skimmed milk (A - 0,1% fat)
12. Four hole tip (standard) - skimmed milk (B - 0,5% fat)
13. Four hole tip (standard) - low-fat milk (C - 1,5% fat)
14. Four hole tip (standard) - low-fat milk (C - 1,5% fat)
15. Four hole tip (standard) - whole milk (E - 3,5% fat) 

16. Four hole tip (special) - skimmed milk (A - 0,1% fat)
17. Four hole tip (special) - skimmed milk (B - 0,5% fat)
18. Four hole tip (special) - low-fat milk (C - 1,5% fat)
19. Four hole tip (special) - low-fat milk (C - 1,5% fat)
20. Four hole tip (special) - whole milk (E - 3,5% fat)

* The special four hole tip is the one with a centered hole and three in the outer ring.

The different milk types; A = skimmed milk, B = skimmed milk, C = low-fat milk, D = Barista milk, E = Whole milk

The different milk types shown above, is primary the drinking assortment from the biggest nordic supplier called Arla, and delivers milk with a fat percent from 0,1% to 3,5% - the developed Latte Art milk is not buyable in every grocery store, but I took it along to see if their experimenting has a proving point. The general lineup from Arla is off 1 l. per milk and consist of homogenized and pasteurized milk, where the Latte Art milk isn't pasteurized but instead highly homogenized. 

Latte Art (D) milk info

The special Latte Art milk has been developed in cooperation with some of the worlds best Baristas. The secret behind the milk is that Arla enriches the milk with its own naturally fat proteins. This provides the milk with the best assumptions to create a soft and velvety foam, that highlights the notes of the coffee. The Latte Art milk is targeted towards any espresso based drink, such as Caffe Latte, Cappuccino and Macchiato. 

The accessories pack of Rocket steam tips

Steam tip info

Rocket have produced  an upgrade kit for their Rocket Espresso machines and fit able for some other produced espresso machines, where you will receive four different designed steam tips, shown in the above picture. This will let you experiment with different frothing techniques, because they will stretch and create a whirlpool in the milk by their own different way. This set is containing a two hole tip, a three hole tip, a standard four hole tip and a four hole tip with three holes in the outer ring and one centered - all this is purchasable for the price of 250 DKK ($42). 

How to attach the different steam tips?

1.Unscrew the standard steam tip

2. Choose which steam tip you want to put in place, swap out the o-ring, and screw it on 

          3. Experiment!

The two hole tip

Two hole tip

The two hole steam tip is what I along with the one hole steam tip, consider to be the starter tip, because it gives you the biggest window of operating your milk correct. With that I mean that the two holes limits the outgoing steam and therefore will the milk be heated a bit slower, which gives you more time to incorporate air into the milk.  

In difference to the single tip solution, the two hole tip is dividing the pitcher up into two areas, which each will have its own "whirlpool". Note the above left picture that shows the flow from a side view - the two hole tip lets the steam escape from these holes, which will push the milk, that the steam wand is mired in. This will create a downforce upon the milk, which will lead the milk towards the bottom of the pitcher and when its reaches - it will bounce backwards towards the surface, where it will be pushed downwards again. This is in other words a whirlpool, where you are able to work the entire milk - meaning you can incorporate air into the entire milk instead of creating a fat top foam layer. 

The three hole tip

Three hole steam tip

The next level of steam tips will be the three holed tip, which will deliver a faster result comparing to the previous described two and single hole tips. The result is quicker delivered, because their will be a more concentrated merging between the hot steam and milk due to the three holes increased limit of exit steam. This will heat the milk faster and therefore also minimize your window of stretching the milk, which is leading this steam tip for more advanced use.

Note the above right picture of the three zones created by the three holed steam tip, which is causing more activity within the milk and therefore a quicker micro foam result. Likewise the quicker result, the steam tip also incorporates air into the milk a lot quicker than the previous steam tips - therefore if you are used to operate with these tips, then slowing down to a two or single hole tip will seem like going from a speedboat to a rowboat.  

The traditional four hole tip

Traditional four hole steam tip

The four hole tip is often represented in the most coffee cafes and is therefore thought off as a professional steam tip - this is because its currently the quickest steam tip at the market, that also can deliver the maximum result of great micro foam. Comparing this specific steam tip along with the previous tips, the speed of the four hole will shine through when frothing for more than one cup of cappuccino. Don't get me wrong, because the steam tip will also be extremely quick when frothing for a single cup - but those people who froth a single cup are they truly seeking a quicker frothing? Im an egotist kind of guy when it comes to coffee and Im always preparing a cup of coffee for myself and therefore my needs for the quickness are relatively low - but when matching result with the other steam tips, I always get the best micro foam result from this one.

The above right picture reveals the four whirlpool zones created by the four hole steam tip, which activates the entire milk within the pitcher - leaving it to heat very quickly. The four hole tip is very aggressive when it comes to letting maximum hot steam out in the pitcher, therefore it isn't preferable if you have a relatively small espresso machine, like the Francis Francis X1 or a Rancilio Silvia, because it will invalidate the steam capacity before you have finish your frothing, leaving a very inconsistent steam power. BUT if your machine possesses the steam capacity than the four tip is always to be preferred, because the activity in the pitcher created by this steam tip, will allow perfect tiny air bobbles incorporated into the milk.

The four hole tip, with a centered hole and three in the outer ring

Special four hole steam tip
This included steam tip in the steam tip pack from Rocket is untraditional, because its a four hole steam tip with a center hole and three in the outer ring of the tip. I haven´t tried it yet, even though I have got one, simply because I can't seem to found out how it can be logically good when frothing milk? More of that below the attached picture - but i theory it would be as aggressive as a normal four hole steam tip and therefore also non-preferable when having a small espresso machine like described before.

The three zones that will be created by this steam tip is equal to the three hole tip, but the center hole will beside these three areas, push the milk downwards and thereby create resistance in the three areas (In my mind). I will try it below and comment if this will be my new favorite steam tip or it will be kept hidden once more.

Steam tip result
The result of the steam tip testing is listed in the above chart, where the frothing time is giving per. combination as well as the difficulty attached to it. The results were supportive of my previous assumptions regarding the increased speed of frothing when using more steaming holes - in other words the frothing is much faster when using a steam tip that allows more hot steam to merge with the milk. I found the standard four hole tip very useful when chasing the lowest amount of time spent on frothing - but the special four hole tip weren´t as quick as the standard, which impressed me a lot.

With that said, speed isn't everything, especially not when the primary focus is upon taste and quality - like mine is. I don't really give a .... if it takes 20 sec. or 10 sec. as long as I get the best/optimal result. So which steam tip would I use myself? Hmm, well I honestly have been using the standard four hole tip for a week by now and I´ve got to know it better than the rest of the steam tips pack - but I'm actually most joyful upon the three hole tip, because it gave me the best velvety results.

I blame it on the time, because I have been practicing with the four hole tip and therefore is used to its quickness of frothing, but with the three hole tip I got those extra seconds, where I could fine-tune my technique and create a bit more richer, smooth and velvety micro foam. This test where also performed with a 0,35 l. pitcher, which is kind of small when using a four hole tip, so I would properly use the four hole tip when frothing in a 0,6 l., 0,75 l. or 1,0 l. pitcher - nevertheless its always nice to have the option to change around a bit.

* I would like to comment especially on the special four hole tip, because I was not very pleased with it during this test, because it sprayed milk out of the pitcher and also created some very big bobbles, when the whirlpools conflicted with each other. Therefore Im certain that I´ll never use this steam tip again and due to that it will be the worst steam tip choice of the pack.

What does very easy, easy, medium and hard mean?

1. Very Easy - the best possible condition when frothing milk, even a newborn coffee enthusiast will not experience any kind of trouble in the pursuit of great micro foam. The milk merging with the hot steam in the pitcher just flows with each other and you are left only to control the steam handle.
2. Easy - its no big deal frothing milk and if you want to produce some excellent frothed milk in front of your friends, then nothing will stop you. This level doesn't require much experience when frothing milk, just the basics about when to stretch the milk and stop heating it.
3. Medium - The milk can be a challenge, but if you have patience and focus you´ll get the job done perfectly. This level requires some attention in the frothing action and is therefore not a simple job, if you want to be rewarded with the perfect micro foam.
4. Hard - The hunt after the perfect micro foam is long gone and you have to struggle to get a decent result. This levels requires every aspect of your concentration and the possibility of failure is greater than success. 

Choice of milk result
I can honestly say that between these five chosen milks lays a huge difference in taste and frothing ability - take for example the skimmed milk with 0,1% of fat, this milk separated when being frothed, leaving a very poor result when poured into the cup. This meaning that the skimmed milk at 0,1% is already out of the competition before is really started, because it was the only that separated, was thin tasting. The second skimmed milk with 0,5% fat were a bit easier to frothed and had some great quality such as great sweetness, thickness and excellent bobbles, but it were lacking when it came to support the coffee flavors and keeping a great depth in flavor.

The whole milk was honestly the most easy milk to get some great frothing results with, but the fat taste of cream affected the final cup a bit too much, to make it the best pick. Therefore was the five milks cut down to two, where they actually did great both. I couldn't really tell them apart, so I would go for the low-fat milk, because it has better options for purchase than the special developed Barista milk.

A final note within the frothing area would be, that frothing the milk actually became more successful when giving the steam tips with more holes, because of the greater steam power and hereby action within the pitcher. The air simply became better incorporated in the milk comparing to the two holed tip for example.

I now this have been an extremely long article and I could have divided it in two or three parts, but I thought it would be interesting reading for you guys, so I wouldn't have you all waiting for the other parts. Hope you enjoyed this review and thereby create your own opinions :)

The Rocket Evoluzione v2 also did magnificent doing these tests, because it just frothed all these milk test without even a single drop in steam capacity even once. Im truly glad for this wonderful machine, its just keep impressing me and increasing my passion for coffee, quality coffee.

// Hendrup