The Machines
If you want to make ice cream, you have to have an ice cream machine. There are no two ways about it. You do have choices, though, when you decide which ice cream maker to bring into your kitchen; they all have pros and cons for you to weigh. The various home models fall into three categories: machines with pre-frozen inserts, machines with built-in compressors, and machines with buckets filled with salt and ice. The physics behind all these machines is identical. In fact, the basic mechanics of ice cream machines haven’t evolved much since the mid-nineteenth century, so let’s start there.
Hand-Crank Salt and Ice Machines
The earliest ice cream makers depended on ice and salt to freeze the ice cream base. The styles vary, but basically these machines are made of an internal metal canister with a fixed double-blade dasher, a larger external bucket, and a top yoke that allows you to crank and turn the internal canister. You fill the canister with liquid ice cream base and submerge it in the bucket, which is then filled with a slush of ice and rock salt. The physical reaction between the salt and ice interferes with the freezing point of water, causing it to melt but stay liquid below 32°F (similar to how sugar prevents water from freezing in your ice cream!). This super-chilled water surrounds the canister, and the ice cream inside will freeze around the edges. As you crank, the canister rotates, and the blades of the dasher scrape the newly frozen ice cream from the walls, stirring it into the liquid ice cream mix. Historically, ice cream was consumed immediately after churning, as there was no refrigeration to further freeze and harden (or store) the frozen dessert.
You can still hand-churn your ice cream in this fashion by using an old-fashioned hand-crank machine. I have one at home, and it makes a wonderful group activity, especially when children are around. You’ll need a large bag of ice, and rock salt (table, kosher, or other cooking salt is too small and just dissolves into the water).
The biggest advantage to this machine is the ability to churn more than one flavor a day, unlike the more-popular machines that use canisters you chill in the freezer a day ahead of time. You can just keep reloading the machine with more salt and ice, and churn ice cream all day long! These machines often can churn bigger batches, too—up to a gallon of ice cream at a time—allowing you to feed large groups of ice cream lovers.
Pre-Frozen Canisters
The most common home ice cream maker has a thick-walled bowl filled with a gel coolant, which requires a 24-hour pre-freeze. A mechanized base rotates the bowl while a plastic double-blade dasher churns inside. The frozen bowl usually retains temperatures below the freezing point of water for 30 to 40 minutes at room temperature. In our recipe testing for this book, we purchased every home ice cream maker with a frozen insert we could find, ten in all. The prices ranged
from $30 to $100, and all of them had the same basic mechanics. The differences in quality came in the bowl’s ability to maintain cold temperatures when in use and the physical strength of the dasher. We had two clear favorites: the Cuisinart countertop model, in either 1½-quart or 2-quart capacity, and the ice cream maker attachment for Kitchen-Aid stand mixers.
The Cuisinart was our all-around favorite, with the best chilling and the strongest paddle. You might be surprised to learn that many professional pastry chefs without the funds for a large-batch freezer rely on these models. I used to make all the ice cream for Eva restaurant in Seattle with a trio of these machines.
The Kitchen-Aid’s blade was strong, and the bowl also stayed cold for a long time, but it won our hearts as the only machine that allows you to churn at different speeds. If you refer to the section on Air in “The Five Components of Ice Cream” (page 20), you’ll see that ice cream’s texture is defined in large part by the amount of air whipped into it, referred to as overrun. Most home ice cream makers churn very slowly, making dense, chewy ice creams. This is great if you love a dense, chewy ice cream. However, there are those among us who like a lighter, softer ice cream, much like the scoops we get in old-fashioned ice cream shops. The Kitchen-Aid allows you to churn your ice cream at a little higher speed and whip a little more air into your scoops. If you do that, you’ll get about 1½ quarts of churned ice cream with each of the recipes in this book, sometimes closer to 2 quarts, depending on the flavor. The biggest advantages to this type of machine are the small footprint, taking up less
of your precious cupboard or counter space, and their relatively low cost. The disadvantage is that it can only be used once in a 24-hour period. Unlike the ice-and-salt machines, or those with built-in compressors, the freezing capability decreases the longer you use it. This means a moderately warm ice cream base may never freeze if added to this machine, and you won’t be able to fix it without freezing the bowl again for 24 hours. When I used these machines in a restaurant, I purchased extra bowls, allowing me more than one churn a day. They are much cheaper than the machine itself, and can live in the freezer until you need them. If you are serious about home-made ice cream, and have the room, an extra bowl will be a great advantage.
Also, if your ice cream needs to churn longer than 30 minutes, keep a watchful eye on it. After that time, the freezing capability of the frozen coolant diminishes greatly, and there will come a point when it no longer freezes. If you continue churning past this point, you will begin to melt your ice cream instead of freezing it. If you don’t see any textural change for 2 minutes, you’ve reached the end of the bowl’s freezing capability.
Built-in Compressors
Professional ice cream manufacturers all use machines with large compressor units that remove heat from the ice cream quickly as it churns with the dashers. There are a handful of ice cream machines with small compressors available to home cooks that work well, offering you the option of churning multiple batches of ice cream in one day, and they do not require planning ahead and pre-freezing an insert.
The capability of a compressor directly affects the quality of the ice cream. The better the compressor, the faster it freezes and the smoother and creamier the ice cream will be. And the better
from $30 to $100, and all of them had the same basic mechanics. The differences in quality came in the bowl’s ability to maintain cold temperatures when in use and the physical strength of the dasher. We had two clear favorites: the Cuisinart countertop model, in either 1½-quart or 2-quart capacity, and the ice cream maker attachment for Kitchen-Aid stand mixers.
The Cuisinart was our all-around favorite, with the best chilling and the strongest paddle. You might be surprised to learn that many professional pastry chefs without the funds for a large-batch freezer rely on these models. I used to make all the ice cream for Eva restaurant in Seattle with a trio of these machines.
The Kitchen-Aid’s blade was strong, and the bowl also stayed cold for a long time, but it won our hearts as the only machine that allows you to churn at different speeds. If you refer to the section on Air in “The Five Components of Ice Cream” (page 20), you’ll see that ice cream’s texture is defined in large part by the amount of air whipped into it, referred to as overrun. Most home ice cream makers churn very slowly, making dense, chewy ice creams. This is great if you love a dense, chewy ice cream. However, there are those among us who like a lighter, softer ice cream, much like the scoops we get in old-fashioned ice cream shops. The Kitchen-Aid allows you to churn your ice cream at a little higher speed and whip a little more air into your scoops. If you do that, you’ll get about 1½ quarts of churned ice cream with each of the recipes in this book, sometimes closer to 2 quarts, depending on the flavor.
The biggest advantages to this type of machine are the compressor, generally the more expensive the machine.
The top-of-the-line home ice cream makers with built-in compressors will cost an arm and a leg. If you are a texture fanatic, and are willing to shell out the big bucks, these are your machines. There are also less expensive models, all with similar capabilities. But for every machine, we found the best results when we turned the compressor on 5 minutes before we added the ice cream base, ensuring the machine was cold when we started churning. This cut the churning time by about 10 minutes, and made noticeably less icy ice cream. Without taking this step, we found the ice cream churned in home compressor models was icier than the scoops we made with pre-frozen canisters.
The above is excerpted from Hello, My Name is Ice Cream, (c) 2017 by Dana Cree. Reproduced by permission of Clarkson Potter. All rights reserved.
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