Block-o-Clock: How To Make Clear Ice
We all love big ice cubes, but did you know that there’s an art behind it? If you’ve been into The Block you’ve may have noticed that our cubes are crystal clear but when you use your tray at home they turn out cloudy. Why?
Buckle up because things are about to get pretty nerdy. When you use your large cube tray at home, whether it’s silicone or plastic, the ice is freezing from all sides at a similar rate. This allows air (gases) that is naturally in the water to get trapped in the center of the cube thus creating a cloudy appearance. The gases also mean that your ice is not as dense and will melt faster. For spirit lovers, this translates to more water in your drink. Don’t worry, the cloudy cubes serve their own purpose. These cubes are perfect as “shaking ice” because when you’re preparing a cocktail it’s important to have a certain amount of dilution, particularly to make egg white drinks frothy. With a clear cube, not only is it beautiful, but it also melts slowly leading to less dilution creating an optimally chilled beverage.
So, how does The Block create such clear cubes? Believe it or not, it’s not about boiling the water or using distilled water, it’s actually all about directional freezing. To start, you need a portable insulated cooler like this one with the top popped. Essentially, this creates an insulated box minus the top which creates the directional freezing (from top down). To make a two-inch cube, you’ll want to have double the amount of water, so fill the cooler with four to six inches of filtered water (do not use tap because of trace amounts of chlorine which gives off flavor). Be sure to use warm water instead of cold since it allows more gas to escape in the freezing process. The hardest part? The wait! For a 9-quart cooler, it can take approximately 44 to 46 hours to freeze and produce a solid block. The key is not allowing the cube to freeze completely. You want some water at the bottom of the cooler which will hold the gases that migrated from the top as freezing occurred.
After 44 hours, pull out your cooler. The bottom of the ice will still be water, which is important. To remove the ice block, place a cutting board in the sink and flip the cooler upside down. As the ice starts to thaw, it gradually falls out of the cooler and the remaining water will be able to drain in the sink. Be prepared for there to be jagged edges at the bottom where the gas was released. If your cooler doesn’t want to pop out, push on the bottom of the cooler to aid it releasing the block of ice.
To start cutting, you’ll need a cutting board, a bread knife, and some gloves. The serrated edge works well to cut your ice using a sawing method. After letting the block sit out for fifteen minutes or so to avoid fracturing, it’s ready to be shaped. Score a line on top of the block to start; once you have a line, you can use the back of your hand or a mallet to break the ice. If you’ve got a chunk taken off, now, it’s time to trim! Have fun and create the best shape for your intended drinks. For example, a rectangle works well for anything in a Collins glass while a square is ideal for old fashioned glasses. When the shaping is done, return the cubes to the freezer. If possible, try not to stack the cubes since they’ll freeze together but it’s not too difficult to separate with a knife.
So, there you go – clear ice! Next time you’re wanting to show off, use these cubes in a cocktail not only for the aesthetic but to create a more delicious drink.