I think you can chalk up that to the high skill level obtained from constant practice in steaming milk (as to why they dont cool the pitchers). I believe as has been stated, the cooling of the pitcher/milk has more to do with lengthening the time required to steam milk than any flavor development.

bob

I took a Latte Art class at the Barefoot Coffee location just before it turned into Chromatic Coffee. They advised to keep the pitchers in the fridge, explaining that it helps give you more time to work the coffee. I told my trainer that I kept them in the freezer and he said I shouldn't do that, I should just keep them in the fridge. I don't remember the justification for this, but I've since switched to keeping them in the fridge. It might be keeping any moisture or condensation away from the pitcher. It's been so long since I've made a milk drink, I think I need to pull them out and clean them up again.

I agree that once you've mastered the skills, you probably don't need to bother with a cold pitcher.

About keeping them in the freezer, I tried that once. They get to zero or below and I got ice crystals in the pitcher. Of course steam converts the ice back, but...

Don't know if that is the reason but maybe.

As for keeping them in the fridge or freezer, if you gonna do that they should be wrapped. Funky stuff in there if you have them there for a while.

Its why I put my pitchers in for a short stint in the freezer, not storage.

Bob

Here are my results from testing the comparable effects of refrigerated and frozen pitchers versus room-temperature pitchers.

In all cases, the milk was poured from the refrigerated carton and swirled in the pitcher for five seconds before measuring the resulting temperature of the milk. In each case the results represent the average temperatures for five trials rounded to the nearest 1/10° F. as measured with a Thermapen thermometer.*

Test A ~ Cappuccino
12 ounce pitcher; 5 ounces refrigerated milk at 36.2° F.; room temperature 70.3° F.; refrigerated pitcher temperature 36.2° F. (same as milk); frozen pitcher temperature -6.1° F.

• Room Temperature pitcher: resulting milk temperature raised by 2.4° F. to 38.6° F.
• Refrigerated pitcher: resulting milk temperature raised by .2° F. to 36.4° F.
• Frozen pitcher: resulting milk temperature reduced by 2.2° F. to 34.0° F.

Test B ~ Latte
18 ounce pitcher; 8 ounces refrigerated milk at 36.2° F.; room temperature 70.6° F. refrigerated pitcher temperature 36.2° F. (same as milk); frozen pitcher temperature -6.1° F.

• Room Temperature pitcher: resulting milk temperature raised by 4.3° F. to 40.5° F.
• Refrigerated pitcher: resulting milk temperature raised by .1° F. to 36.3° F.
• Frozen pitcher: resulting milk temperature reduced by 3.2° F. to 33.0° F.

Interpretation of Results:
Using the commonly held belief that the added steaming period afforded by colder milk is advantageous up to about 100° F., (and that the temperature increase from steaming is linear over time), refrigerated or frozen pitchers will provide some small amount of additional working time.**

For a cappuccino:

• With a refrigerated pitcher, the barista will have additional time to raise the milk an extra 2.2° F. to the 100° mark - from a 61.4° span to 63.6°, an extra 3.6%. So for example, if the usual steaming time to raise this 5 oz. milk to 100° is 10 seconds, the barista will have an extra .4 seconds of working time (or .7 seconds if the steaming time to 100° is normally 20 seconds with a slower-steaming machine).
• With a frozen pitcher, the time to 100% expands from 61.4° to 66.0° - providing an extra 7.5% working time to 100°. This would translate to .7 seconds extra time assuming a usual 10-second time, or 1.5 seconds with a slower machine that normally requires 20 seconds.

For a latte:

• With a refrigerated pitcher, the barista will have additional time to raise the milk an extra 4.3° F. to the 100° mark - from a 59.5° span to 63.7°, an extra 7.1%. So if the usual steaming time to raise the 8 oz. milk to 100° is 15 seconds for example, the barista will have an extra 1.1 seconds of working time (2.1 seconds additional time with a slower machine if its normal steaming time to 100° is 30 seconds).
• With a frozen pitcher, the time to 100% expands to require a temperature rise of 67.0° instead of 59.5° - providing an extra 7.5% working time to 100°. This would translate to 1.9 seconds extra working time assuming a normal 15-second duration (or 3.8 seconds with a machine that normally requires 30 seconds).

Conclusion:
The manifest benefits of filling one's refrigerator or freezer with steaming pitchers at the expense of domestic harmony are not entirely clear.

• * The variations among the five trials for all the tests were very small (only +/- .2° F.). Especially with the small number of sample trials, I did not calculate variance or confidence intervals - these would not be meaningful given the character of the test and its results.
  
  ** Inexact 2x multiples in the number-of-seconds calculations across the example steaming times are the result of rounding error.

Swirling the milk for 5 seconds in the pitcher is hardly enough time. The pitcher is still colder than room temp after that time, and will require still more energy to heat up. I think you need to actually time steaming in order to get an answer, but it's definitely more than .7 seconds.

At home I keep mine in the freezer, at work in the fridge. Either is fine but when steaming 4oz of milk on a commercial machine it does help. When using a 20oz pitcher (which many other professional baristas seem to do even for the smallest drinks, which I think is pretty lame of them) I don't really care.

I for one keep mine at room temp. In my belief and as previous posts state it just allows more time to get the texture. I also use my pitcher for hot water, tea and other hot beverage related drinks.

No matter what "everyone" and "every barista" says, the physics of a thin, stainless steel pitcher containing an appropriate amount of liquid are such that pre-chilling the pitcher to refrigerator OR freezer temperature cannot make a meaningful difference in total steaming time.

Besides longer steaming isn't better it's just longer. If, after a few weeks of practice, you can't steam 4oz of milk to latte art quality without an extra two seconds, the problem isn't time. On the contrary, the faster you can get to the right texture the better. Cook milk too long, and it's cheese.

BDL

I keep the fridge setting just above freezing, this seems to make more difference in gaining at few extra seconds stretching time than a cold pitcher.

When splitting milk to pour multiple drinks, i actually preheat the smaller pouring pitcher with a couple oz of boiling water It stops the milk losing too much heat as its transferred so the drinks all get served close to the final steaming temp.

Anvan wrote:Conclusion:
...The manifest benefits of filling one's refrigerator or freezer with steaming pitchers at the expense of domestic harmony are not entirely clear.

AWESOME!

Nurk2 wrote:
Anvan wrote:Conclusion:
...The manifest benefits of filling one's refrigerator or freezer with steaming pitchers at the expense of domestic harmony are not entirely clear.

AWESOME!

I didn't catch that the first time read it. I got a big ol' when I told my gf I wanted to make room for my milk pitcher in the fridge. Love her to death, she supports my hobbies and was will to reorganize a shelf on the fridge door.