posted by Dave Arnold
A while back we did a post on whether or not the type of ice you use in a shaker affects the dilution and temperature of your finished cocktail. Turns out it doesn’t (most of the time). For the nitty-gritty see here and here. Most people say, “Yeah, I know about your results — but we all know that crappy ice dilutes drinks more. If you shake a drink with crushed ice it will get watery.”
This is both true and false. Here are my thoughts:
- Bar ice is at 0 degrees C (just believe it). Therefore,
- All chilling is through melting (read our two previous posts, links above, if you need proof).
- The smaller the individual pieces of ice are, the greater their surface area per gram.
- Because the ice is at 0 degrees C it is wet — water is on the surface.
- The greater the surface area, the more water on the surface of the ice. So….
- Shaking with small ice makes the drink watery right away. The ice brings its own water. After the initial dilution, small ice and big ice will behave identically (with respect to dilution and temperature).
Fact 2 is the single most important thing to remember about shaking. Because all chilling happens through melting, for a given amount of chilling there will be a given amount of melting. There is a one-to-one relationship. As long as the surface area of the ice is large enough –and the agitation of the shaking is great enough (which it usually is)– the size or type of ice shouldn’t matter much. BUT….
About two months ago, Don Lee from Momofuku Ssam bar and John Deragon, formerly of PDT, came in to test this hypothesis. Unfortunately, I lost all the photos (don’t ask). About a month ago we re-ran the experiment and got the same results. Not a hundred percent scientific but here it is:
Hypothesis: The extra dilution bartenders experience when using crushed ice comes from water adhering to the surface of the ice.
Test: Dry off some crushed ice and whole ice, shake them both with booze and measure the alcohol content.
We measured equal amounts of 901 tequila… Justin Timberlake’s tequila. The tequila that is bringing sexy back (can we get more free crap yet).
We put ice in a bag and crushed the heck out of it with a rolling-pin.
We put the crushed ice and and some whole ice in separate bags. We cut holes in the bags for drainage and put them in a centrifuge over drainage racks. We lightly and quickly spun the bags to throw off excess water. The centrifuge is one hell of a salad spinner.
With great celerity we measured equal weights of crushed and whole ice and shook them with the tequila at the same time for the identical number of shakes. We strained them at the same time through a chinois, to remove the effect of ice crystals.
Both drinks had the same volume and both registered 21.5% ABV.
Then we did the same experiment with crushed ice and whole ice that hadn’t been spun in the centrifuge. The whole ice came in at 21% ABV, slightly more diluted than the spin-dried whole ice. The crushed ice came in at 20% ABV, a lot more diluted than the spin-dried crushed ice.
Some Calculations: Let’s assume that all ice comes in perfect cubes. A single cube 5x5x5 centimeters has a surface area of 150 square centimeters and weighs 115 grams (ice has a density of 0.92g/cc). It would take 125 ice cubes measuring 1x1x1 centimeters to have the same weight. Those ice cubes would have a surface area of 750 square centimeters. It would take 1000 ice cubes half a centimeter on a side to have the same weight and they would have a surface area of 1500 square centimeters. The surface area adds up pretty quickly –so does the entrained water.