When I make martinis, the recipe I use is 2.5 fluid ounces1 of gin2 and 1/2 fluid ounce dry vermouth3, shaken or stirred4 with 7 ice cubes5, then strained into a cocktail glass (I mix until it's cold enough, and not for some specific length of time.)
If I use less ice, the martini is more diluted; if I use more ice, the martini is stronger (too strong in fact—I prefer some dilution.)
With a lot of ice, the drink chills very fast, not giving the ice as much time to melt, and vice-versa.
think I am crazy about the amount of ice6. They claim that (a) the ice has to melt to chill the drink so no matter how much ice I start with, the same amount is melted to reach the desired temperature, and (b) I had to retake Physics 2A in college7, so what do I know anyway?
I pointed out that I could chill the drink with really cold rocks (a.k.a. whiskey stones) and it could get just as cold with no melting and maybe they are missing something.
The answers to these questions seem to support my friends' argument that the melting of the ice is the overwhelming contributor to the cooling:
- What cools a drink?
- Is an ice globe the worst possible way to cool a drink (with ice)?
- Calculate mass of ice needed to cool water $\Delta$T degrees
However my experiment seems to demonstrate otherwise.
I tested this by making six martinis, two each with 4, 7, and 10 ice cubes. I used the same amount of gin and vermouth in each. I weighed8 the ingredients before adding them to the mixing cup. I stirred until the desired temperature9 was achieved. Then I weighed the amount after straining.
The 4-cube martinis gained more weight than the 7-cube martinis, which in turned gained more weight than the 10-cube martinis. I assume the weight gain was the melted ice. My friends happily drank all the martinis, but remained unconvinced of my Physics acumen, either theoretical or experimental10.
Am I exhibiting confirmation bias and my stupid friends are right? Or is there an explanation for my hypothesis and observation and they should finally shut up about my having to retake Physics 2A because come on it was like 30 years ago already and besides, I'm not using Planck's constant to calculate how long it takes atoms to slow to a halt, I'm just making martinis!
Is the ratio of nearly 2:1 ice-to-liquid a factor? How about the constant mixing? Or is this dependent on the starting temperature of the ice and even though the warming of the ice contributes very little, it is enough to affect the outcome?
Apologies for the use of American measurements in this scholarly context, but that's what my utensils are labeled with.
No apologies for the insistence on gin. If you want to use vodka or make some other cocktail and call it a martini, we have nothing further to discuss.
I use a 5:1 ratio. Others may quibble. They are wrong.
Seriously, I do not care. Can I please continue?
For my ice trays, this is 5 fluid ounces of water, prior to freezing, in a plain old kitchen freezer.
Although they are all too happy to drink the martinis I make.
These are friends that I went to college with so I can't argue that point, but there were three intramural softball playoff games the weekend before finals, so when was I going to study? But I digress...
Postal scale, accurate to 1/10 (American again) ounce, sorry.
28 degrees American Fahrenheit on my kitchen thermometer that measures to 1/10 degree, but accuracy unknown.
I am willing to rerun that experiment as long as necessary until I get it right!
I appreciate the answers and I am accepting the answer from @cyberx86 because (a) it independently supports my insistence that 7 ice cubes is The Right Number, and (b) What kind of physics site would we have if we didn't reward showing your work?
However no one really "put a bow on it" so I'll add
Since the final temperature of the martini drops below 0° C and there is also ice melting, there must be both melting and absorption occurring together during the mixing.
The measurable change in the amount of melting in this case is due to the addition of the heat absorption capacity of more ice, but only because it is below 0° C to start with.