Frothing Pitcher: The Significance of Size (on the finished product)

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TheCappuccinoKid
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Joined: 7 years ago

#1: Post by TheCappuccinoKid »

I made a particular finding today with a frothing pitcher, and I haven't seen this said anywhere, so if it's already well known, I'll go about deleting this post. Here's the back story:

For months I've owned a "Quickmill Retro 0835" espresso machine, which uses a thermoblock for the boiler and steam function. I have never made good milk froth on it. On a good day, I might be able to produce something that can look like something white floating on top of the brown crema. Not much, and I could not even come close to anything that I can use to do latte art. With the plastic frothing aid, creating foam for cappas is much easier. But as I mentioned in my last post here, it is a PITA to clean the steam wand with the plastic frothing aid attached. So I've taken to just using the machine without it.

But with no frothing aid, trying to produce anything I can work with on the QM is a pretty sad affair. Either I end up with underheated warm milk - that has no body, no microfoam to speak of. Or overheated milk that has curdled - broken up, as it's gone past its ideal heating point. Creating the whirlpool effect is not a problem, as I'm usually able to do that. And it doesn't matter whether the tip of the steam wand is submerged, riding the surface, a combo of the two, a steady hand, a non-steady swirling hand that heats up all points around the surface... it just doesn't matter to the end effect! While all these things do have an effect, I was just not able to create either good, plenty cappa foam or latte-ready microfoam.

I tried different pitchers, thinking this may be the key. I always do milk frothing for one person, and that's usually about 100ml of milk (between 80ml and 120ml). So I always wanted to use a small pitcher size. This aligned with reading comments from espresso people talking about how the milk should go half way up the pitcher; etc. Also, my QM steam wand has about 4" of clearance between the tip and top of the machine. So I can't exactly stick a milk jug in there. I had tried 4 different stainless steel pitchers/mugs; 3 are pictured here:



I usually used a size that's about 8oz. But I also tried a tall stainless cup (not pictured), about 12 - 16?oz. (similar to what you'd find in a stainless steel shaker). I also got a temperature gauge specifically for measuring the heat of the milk during frothing. That helped, but it didn't solve the problem of lousy frothed milk. (Mostly just heated milk that would end up actually cooling the coffee and producing a cup of lukewarm java... since the milk had to sit around while the espresso was being brewed).

Producing frothed milk is known to be one of the weak points of my machine (it has no variable steam output, and produces its steam power in short bursts of about 1s on / 3s off). Thus I resigned myself to the idea that I would never get the right results I want for lattes; or even cappuccinos. So I had to seriously start thinking about switching my beloved Quickmill for one of my other machines, that I know can do good milk froth. It seemed like after dozens and dozens of attempts, 4 stainless steel frothing pitchers (another one on order being shipped) and a temp gauge, the quirky thermoblock-driven steam wand just wasn't ever going to come up with the goods.

However, I did come across this item at a thrift store today:



It is HUGE, compared to anything I've ever used. I thought I would give it a shot, because at least it felt like a good quality. The bottom was stamped "ILSA", 18/10 (stainless), Made in Italy. But this monster pitcher is like 28oz. I've not heard of a frothing pitcher this big, so I don't know if that was its original function, or if it was meant for something other than espresso making.

However, when I did use it to froth milk... wow! It was, what they call a "revelatory experience". The milk did not behave as it did in all other attempts. For one, there was a much more marked difference notable when the steam wand tip was submerged or closer to the surface. Even the temperature gauge did not behave as before. I could not help but notice I had 3 times as much time to produce the desired effect before the temp gauge would reach the green zone (indicating the milk was at its max heating point). And when it did reach that max temp, I was still able to hold the pitcher, despite the blazing hot liquid inside. That's because the steel used is a quality, heavy grade of steel, quite unlike the very thin walls of my small, cheap 1 cup mug that I was using as a frothing pitcher (the all steel one pictured).

Actually, the ILSA pitcher got to that desired effect -before- even reaching the green zone! The effect it achieved was scads of thick ultra-creamy microfoam... and for the very first time with this machine (and probably any of my machines), I was able to easily coat the side wall of the pitcher. The elusive "wet paint effect", that I was always looking for and never really got. The foam produced on this first attempt, while perfect for cappas, was not quite what I was after for lattes... but its a very good sign that I can maybe produce latte-ready microfoam in subsequent attempts.

So I concluded from this something different than what "traditional wisdom" states in the espresso community (including comments I read on this site on this subject): that a smaller pitcher is better for frothing milk for a single serving of espresso. And that the design of my machine wasn't really what was holding me back. It was the very fact that the pitcher is large, meant the larger surface area would take more time to heat up, which meant you could inject more steam/air into the milk before your time is up, and you've hit the temperature ceiling and have to remove the pitcher and live with your results; sorry as they may be. The "more steam" allows for more foam. I also suspect the quality/thickness of the steel comes into play at a certain point. The shape I'm less sure about. It's a straight side (as opposed to one that slopes outward from the middle), but I did not notice any problem creating a whirlpool effect.

Ellejaycafe
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#2: Post by Ellejaycafe »

All of those pitchers are very "oddly" shaped for frothing milk in my opinion. I find it harder to produce microform in a large pitcher. I would suggest getting a more traditional style pitcher like this one

https://www.espressoparts.com/frothing- ... esso-parts
LMWDP #544

TheCappuccinoKid (original poster)
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#3: Post by TheCappuccinoKid (original poster) »

That looks to be a 12oz pitcher with a slightly outward slope starting from the middle. So apart from the size, the key difference here is sloped vs. straight sided. (I've read many advocates of both shapes). I actually have one similar to that on order, that I am awaiting on its arrival. So I guess I'll be able to compare it with the large straight-sided ILSA pitcher, that made such a big difference on my machine.

It should be stated (as some people don't always get this!), that not all espresso machines are created equal in the steam dept. In particular, machines like my Quickmill thermoblock that pulse the steam (as opposed to a continuous flow) and do not have variable steam power. With variable steam power, you can maybe get away with using a small pitcher for a small quantity, by starting out with a low steam power. But when the steam power is full on all the time, you can expect to have to use a different approach in certain situations. It seems clear enough now that my machine is more likely to work better with larger pitchers.... 12oz minimum to - maybe 20oz. (The 28oz ILSA is a bit large to be ideal!).

jwCrema
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#4: Post by jwCrema »

I don't have a QM, and can't speak to its frothing aid, but the ones I have seen & tried on other machines are best left in the original plastic in the drawer. Reading through your post a few times took me to the resources page and then to how to on this site: https://www.coffeegeek.com/guides/frothingguide. This post is so key that it shows up twice with an inch of each other. It's in the How To and the Latte Art section. Without repeating or maiming better content than I can write, I will say the symptom of foam on top isn't caused by the pitcher size.

I size the pitcher to may target pour as about 2x my foam objective. For a six ounce cup I use a 12 oz pitcher. For two 6 oz cups, I would use a 600 ml / 20 oz pitcher. I have two favorite pitchers - I get great foam with Toroids on my Cremina with the original 4 hole steam wand.

http://espro.ca/toroid. They explain what's going on during steaming and I find a get better swirl more easily with this pitcher than my others. But the other pitchers also work, I just have to work a little harder on technique.

I also like the Decent Espresso pitchers.

mrjag
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#5: Post by mrjag »

We have different machines (BDB vs QM) so the technique may not translate exactly, but I had a lot of trouble getting the right milk texture until I realized there are two ways you can swirl the milk:
  • toilet bowl swirl - the milk spins clockwise or counter-clockwise, creating a vortex in the center where the milk is sucked downwards.
  • vertical roll - the milk rolls end over end, continually folding on itself.
The goal of swirling the milk is to homogenize the texture, breaking up larger bubbles and equally distributing the pockets of air throughout the milk. I think on consumer machines that the toilet bowl swirl does not spin fast enough for the central vortex to sufficiently move milk from the top to the bottom of the pitcher. What you end up with is two layers of milk: a thicker fluffy layer and a thinner liquid layer. This doesn't work for latte art. With the vertical rolling method you are directly pushing the top layer of milk to the bottom and letting it roll back to the top. This helps evenly distribute those air pockets so that you end up with a better texture from top to bottom.

Here's a pretty good visual of what I aim for, (taken from New Andreja owner with microfoam problem):
Image

I started having MUCH better milk texture after switching to this technique.

My process is:
1. add milk to a little under where the spout starts to flair out from the pitcher
2. purge the steam wand of condensed water
3. incorporate air by skimming the surface of the milk with the wand tip, trying to get that classic paper tearing sound
4. build the velvet texture by vertically rolling the milk.
5. stop steaming when you reach your target temperature. (I stop at ~140°F)
6. tap the pitcher to burst any lingering surface bubbles, then a quick hand swirl to re-blend the milk texture.

Some additional notes:
  • In step 1 you can go as high where the base of the spout meets the side of the pitcher. I use ~170-180ml of milk in my 12oz rattleware pitcher (https://www.amazon.com/gp/product/B0016CBMYY/)
  • For step 3 - I angle my steam wand so that it's 45° or so, similar to this picture..
    When looking straight down into the pitcher, the tip is placed 0.5cm from the center, at 9 o'clock. How much volume you need to build is a trial and error processes, but for me it's about 1-2 finger widths higher up the pitcher side than what I started with.
  • For step 4 - I drop the wand angle so that it's basically straight up/down, tilt the pitcher back just slightly so it mirrors that vertical roll illustration, then submerge the wand tip up to where it attaches to the wand (approximately 2cm).
  • For step 5 - A thermometer is the best way to gauge, but it's approximately 4-5s after the pitcher is no longer comfortable to hold.

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jchung
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#6: Post by jchung »

I thought it was common to use both the toilet bowl and vertical roll method to froth milk. At least I do on my BDB.

Basically...

1. I fill the pitcher to a little blow half.
2. I put my thermometer into the pitcher (very important)
3. I start with the toilet bowl swirl for the initial frothing. I generally froth until the the volume is a little above half, maybe 2/3rds.
4. I move the tip to the center rear and get a vertical roll going which incorporates the foam and milk along with breaking up any large bubbles which might have formed (almost never).
5. I keep the vertical roll going until the temp reaches ~ 140F and then I stop.
6. I knock the pitcher on the counter a couple times if there are still some persistent bubbles
7. Then I swirl the milk in the pitcher which further incorporates the foam and milk. Should have a look sort of like wet paint.
8. Then I start to pour.

shanec
Posts: 118
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#7: Post by shanec »

mrjag wrote:We have different machines (BDB vs QM) so the technique may not translate exactly, but I had a lot of trouble getting the right milk texture until I realized there are two ways you can swirl the milk:
  • toilet bowl swirl - the milk spins clockwise or counter-clockwise, creating a vortex in the center where the milk is sucked downwards.
  • vertical roll - the milk rolls end over end, continually folding on itself.
The goal of swirling the milk is to homogenize the texture, breaking up larger bubbles and equally distributing the pockets of air throughout the milk. I think on consumer machines that the toilet bowl swirl does not spin fast enough for the central vortex to sufficiently move milk from the top to the bottom of the pitcher. What you end up with is two layers of milk: a thicker fluffy layer and a thinner liquid layer. This doesn't work for latte art. With the vertical rolling method you are directly pushing the top layer of milk to the bottom and letting it roll back to the top. This helps evenly distribute those air pockets so that you end up with a better texture from top to bottom.

Here's a pretty good visual of what I aim for, (taken from New Andreja owner with microfoam problem):
<image>
Can anyone point to a good video that shows this vertical roll on a prosumer espresso machine that doesn't have the power for the circular swirl? I have never been able to successfully pull off the vertical roll, but maybe I am expecting it to look different on the surface than it actually should.

mrjag
Posts: 343
Joined: 9 years ago

#8: Post by mrjag replying to shanec »

I'm not aware of any videos already out there so I just tried to record one and it was a total failure. Steaming milk 1 handed is apparently not one of my talents. I'll see if I can get someone to hold the phone/camera when I try again later.

TheCappuccinoKid (original poster)
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#9: Post by TheCappuccinoKid (original poster) »

Ok, so I finally received the espresso-specific frothing pitcher I ordered, so I now have something to compare the others to:



It's a 350ml size (about 12oz.), with just a slight outward slope. 4 rivets on the handles and a relatively thick body.... Quality-wise it does not compare to the ILSA, but I'd say the quality is pretty good for $8U.S. shipped from China off eBay! It's more than good enough for the job, since my first attempt on it produced latte-ready and quite creamy milk. (I placed the tip close to the bottom of the spout, near the top of the milk most of the time, with the pitcher at a 45d angle, until the sound was right; ie. quietest). I was able to have the milk float on the crema, but just wasn't able to produce lovely leaf art picture this time, since it was only my first real attempt at latte art!. Nonetheless, I'm jazzed about the very fact that I can do latte art now. I thought latte art would not be possible on the QM, due to the limitations of the thermo-driven steam function, and its reputation for creating a "stiff" foam.

Compared to the large 28oz. ILSA pitcher, I'd say things are easier with the larger pitcher. There is definitely an advantage to a larger pitcher. For one thing, this 12oz. pitcher heats up the milk faster, so you have a smaller window of time to do your thing, before the milk gets too hot. But the 28oz one is too large, particularly for one serving of cappuccino. This 350ml. is a good size for such a task; given the size of the Quickmill's steam wand and the fact that I only ever do one cappa at a time. Even if its a little trickier to use and master, it's better to use this size. I like it, I think I'll keep it!

Nunas
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#10: Post by Nunas »

There is definitely an advantage to a larger pitcher.
True, but for some there is also a disadvantage, certainly there is in going to big or too heavy. The greater the mass of the pitcher the longer the milk must be steamed to bring it up to temperature. The longer the milk is steamed the more water will be introduced from the condensing steam. So, as a learning tool, it could be very helpful to show the process down. But as a production tool, I want to create the micro foam as quickly as possible to avoid watering down the milk. With my lightest jug I add about 35 g of water for a double cap. With my heavier jug it's around 45 g. This can affect the mouth feel.

One more thing about watering down milk. We all give our steam wand a little burst to clear any water in it. I've measured the resultant water and it's a few drops only (from my Magister in any case). On the other hand, as noted above, it is easy to accumulate quite a bit of water from excessively long steaming.

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