Directional freezing

Okay, imagine you have a cup of water. Now, imagine you put that cup of water in the freezer. As the water gets colder and colder, it starts to freeze (turn into ice). But it doesn't freeze all at once. Instead, it starts to freeze from the outside and works its way inward.

Directional freezing is when you freeze something (usually food) in a way that makes sure it freezes from one specific direction. This can be useful for a few reasons.

One reason is that it can help preserve the quality of the food. For example, let's say you want to freeze a steak. If you just put the steak in the freezer, it will freeze from the outside and work its way inward. This means that the outside of the steak will be frozen for a longer time than the inside. This can cause the steak to lose moisture and become dry and tough.

But if you use directional freezing, you can make sure the steak freezes from the inside out. This means that the outside of the steak won't be frozen for as long, so it will stay juicier and more tender when you cook it later.

So how do you do directional freezing? One way is to use a special freezing apparatus that works kind of like a blast freezer. This freezer blows cold air (usually around -30°C) at the food from a specific direction. This causes the food to freeze from that direction first.

Another way is to use an insulated container and freeze the food at a very low temperature (again, around -30°C). You put the food in the container and then slowly lower it into a bath of liquid nitrogen. This freezes the food quickly from the bottom up.

Overall, the key takeaway is that directional freezing is a way to freeze food in a way that preserves its quality by making sure it freezes from a specific direction.