What is the difference between direct and reverse spherification?

It can be hard to decide what technique to use when you have options. It’s good to know that you're trying to get as much information because it really helps to know about a method before actually trying it.

The main difference between reverse spherification and direct spherification is where the gelling agent is put. For reverse spherification gelling agents are added to the setting bath, while in direct spherification you put it in the base. This results in film growing outwards for the first technique and film growing inwards for the second one.

This may seem like a small difference but it can play a big role in how the spheres are formed and the results that you want to get. If you are looking to make your spheres ahead of time then it is best to use reverse spherification since the spheres set after being removed from the bath. With direct spherification the spheres continue to gel and become solid after some time so these need have a shorter shelf life and need to be served quickly. Personally, I find reverse spherification easier to do and you might want to start off with this too.