Episode 012

The History of Ice

If you think about the cocktail as a truly American beverage, then you’ve got to ask yourself where and how these first bartenders got their ice. And, because we know that the cocktail came of age in the 19th century, we’ll start a little before that.

Since the beginning of our nation, ice was harvested from lakes and ponds in the northern states that received solid enough freezes. It was stored in highly-insulated coolers called “Ice Houses,” and delivered to the wealthy and to commercial establishments like hotels, restaurants, bars, and taverns.

This meant that ice was both highly seasonal and likely extremely expensive during the summer and autumn–which is ironic because the warm months are when you crave a cool drink the most.

Flash forward to 1835, and we see an American inventor, Jacob Perkins, issued a patent for a “vapor compression refrigeration cycle.” In other words, this is one of the earliest versions of the compressor that runs your household refrigerator and freezer. After Perkins, numerous patents were filed by Americans and foreigners alike, which resulted in advances like the refrigerated box car, which allowed for faster westward expansion, and, eventually, the household refrigerator.

Since most of these inventions weren’t powerful to actually generate ice until the late 1800s and early 1900s, bars still used ice blocks harvested during winter, but advances in both insulation and refrigeration made ice a bit more cost effective, and therefore more widely used in cocktails as time went on.

Flash forward from then to now.

Today, when we want ice, we do one of three things:

1. We take an ice cube tray, fill it with water, stick it in the freezer, and wait.
2. We push the button on the side of the fridge, and out tumble cubes or crushed ice.
3. We run to the store and grab a 5 lb bag of pre-made ice.

But what we don’t usually think about is the fact that all these various kinds of ice look different.

The stuff from the freezer is clearer the larger the cubes are. The stuff that comes out of the refrigerator door is usually slender and really cloudy. And the stuff in the 5 lb bag is either flat and pillow-shaped or looks like a tiny hollow cylinder.

This is because different types of ice are used for different purposes. The stuff in your fridge door is most often used for chilling water or other non-boozy beverages. And so coldness is the key factor. And the ice in the 5 lb bags is most often just dumped into a cooler and used to chill down drinks, so it’s produced in whatever way is cheapest for ice companies to make.

But what happens when we start caring about the flavor and aesthetic implications of our ice choices in cocktails? That’s when things get a bit more complicated.

In the glass, we often want a piece of ice that is large and crystal clear. And sometimes, we even have preferences about what shape that ice should be.

For example, if you’re sipping a really nice Old Fashioned on the rocks and you want to sit there and savor every drop, you don’t want your ice melting super-quickly and watering down the drink.

This means you want a cube with a small amount of surface area relative to its size.

Think of it this way: two one-inch ice cubes have way more surface area than a single two-inch cube, which means they’ll melt at a faster rate.

Another way to cut down on surface area is to adjust the shape of the cube. It’s a mathematical fact that spheres have less surface area than cubes, and so if you want to get even less and slower dilution, an ice sphere might be your best bet.

On the market, there are a number of different options for making cubes and spheres of various sizes, but I find that starting out, you really only need to invest in one or two of those “large cube” molds.

Making Crystal Clear Ice at Home

Now, let’s say you’re the kind of person who wants an incredibly clear, beautiful, shapely ice cube in your drink.

The most important thing for you to know in order to produce these in your own home is the concept of “directional freezing.” This basically means that water freezes from the top down, and from the outside in.

Think about a pond in winter. First, a thin film of ice forms across the top of the pond, and then that ice gradually thickens from the top down. Now, the difference between ponds and ice cube trays is that ponds rarely have enough time and cold weather to freeze completely.  If they did, a layer of ice would eventually form around the entire outside and bottom of the pond, and the ice would then freeze from the outside in.

In your freezer, the concept of directional freezing combines with water’s “universal solvent” trait to reveal the key to perfectly clear ice.

If you look at an ice cube you made in your freezer, you’ll probably see a clear layer at the top, a thinner clear layer on the sizes and bottom, and a cloudy center. What happens here is that, as water freezes, the impurities, air bubbles, and minerals dissolved in that water are pushed toward the center of the cube, where the water has not yet frozen. Eventually, there’s nowhere left to go, and so the water freezes around them, but the result is the aforementioned cloudiness.

So, the best way to get crystal clear ice is to freeze your water in as large a container as possible–a small cooler is usually the best at-home option. So, you fill that with water, wait a couple days, and then you’ve got a solid block of ice, with much of it being clear.

You can use a serrated knife to score above the cloudy portion of the block, then gently tap in with a chisel and a mallet, and usually you get a pretty clean break. At that point, you can go to town and use that serrated blade along with your hammer and chisel to create whatever size and shape of cubes you’d like.

This process lends itself more to video than it does to audio, and so hopefully in the near future, we’ll have the chance to put a nice tutorial up on YouTube.

For example, a cocktail that contains a healthy amount of citrus juice and maybe some simple syrup will be able to effectively mask a higher amount of alcohol burn than a drink with exclusively boozy components. Add to this equation the fact that most citrus cocktails are shaken rather than stirred, and you have a higher dilution rate, which further masks the alcohol and softens the acidity of the drink.

Keeping in mind that stirring generally results in less dilution than shaking, an easy way to answer the question, “should I shake or should I stir?”, is to figure out if your cocktail is intended to be on the boozy side, like a Martini, an Old Fashioned, or a Negroni, or if it’s meant to taste softer and fruitier, like a good tiki drink. Stir the boozy drinks, and shake the fruity ones.

Another thing to consider is clarity. When you shake a cocktail, you’re creating hundreds of tiny ice chips in the shaker, and as these melt, the drink very often becomes cloudy, since there’s still that active thermodynamic change taking place. So, if you want your cocktail to be perfectly clear, stirring is a good way to go.

Dilution Hacks

Personally, one trick I’ve seen professional bartenders use when they want to shake a drink, but they’re also looking to minimize dilution, is they use a couple large ice cubes in the shaker instead of a handful of small ones. Then, they shake the drink for a longer period of time, and more gently than normal, such that less of those small ice chunks are going to break off. This ensures a well-chilled drink with good integration of citrus ingredients, but with less dilution.

The Dry Shake

Another option is the so-called “dry shake,” which is exactly what it sounds like. Let’s say you’ve got a complicated cocktail that may contain dairy or egg white components—like a whiskey sour or a Ramos Gin Fizz. In many cases, bartenders will employ a dry shake at first to make sure all the ingredients are mixed together before they add ice. Then, they add the ice and shake again, but perhaps for a shorter period of time than they would if the ice was added right at the beginning of the process. This way, they can hit that dilution “sweet spot” and avoid watering down the drink. So, the moral of the story here is that if you’re having issues with dilution, using a dry shake BEFORE you add your ice to the shaker could be the solution you’re looking for.

Finally, I’d like to address the topic of crushed ice, specifically when it comes to the role it plays in cocktails. Unlike ice cubes or chunks, crushed ice is rarely used in the production of the cocktail. You’ll see it appear most often in hot-weather drinks like certain juleps, cobblers, and tiki cocktails, and in many cases traditionally in a metal or insulated vessel. The purpose of crushed ice is mostly for the maintenance optimal drink coldness, rather than for the actual creation of the cocktail, so if you’re wondering what would happen if you mix up an old fashioned with crushed ice—it would be super watery. Don’t do it.

I know this is all fairly technical and complicated, so I welcome you to email podcast@modernbarcart.com with any questions about dilution or any other ice-related topics, and we’ll be happy to chat with you and lend some more technical advice.

Ice Accessories

Before I leave you here, I’m gonna review a few ice-related cocktail products and basically weigh in on who might want to purchase them for their home bar.

Large Ice Cube Molds

First up, large ice cube molds. These made a BIG impact in my ability to enjoy whiskey cocktails, and it also allowed me to more slowly enjoy certain cocktails that are boozy, but traditionally served up in a coupe glass–like a Negroni or a Boulevardier. The minimal dilution in those cases is a big advantage.

So, I’d say everyone should invest in at least one of the large ice cube molds.

Other ice Cube Molds

There are, of course, ice molds in pretty much every shape under the sun. Long, slender cubes for Collins glasses, sphere molds, and even novelty shapes. If any of these appeal to you, then you are their audience and you should buy them. I think they can definitely add a bit of whimsy to the presentation of the drink, but I’d say that the majority of you listening probably aren’t going to lose sleep if you don’t have them.

Ice Bucket and Tongs

An ice bucket is a really great tool for outdoor or porch-centered entertaining, as well is if your cocktail prep space happens to be separated from the space where your ice resides. Definitely recommend picking one up if either of those situations apply to you.

Lewis Bag and Mallet

When it comes to breaking ice, there is one tool called a Lewis Bag and Mallet, that allows you to basically place your ice block in a leather bag and beat the hell out of it with a wooden mallet.

Again, if this sounds appealing to you, then you are the audience for this product and you should buy it.

Whiskey Stones

As a bonus, I’ll also weigh in on “whiskey stones,” which are those little granite rocks sold in fancy stores. And you’re supposed to put them in your freezer to chill down and then use them in your whiskey instead of ice so that your drink doesn’t get watered down.

Two things here:

1. They don’t work in that they completely fail to chill down your whiskey.
2. It’s a well documented observation that adding a bit of water (or ice) to your whiskey actually enhances the ability to perceive some of the flavor notes that the alcohol burn initially masks. So why wouldn’t you want to water down your whiskey?

Just my two cents there, but I think you should channel your whiskey stone money into some big ice cube trays.