We use vanilla extract in nearly all baking recipes, so it isn’t a surprise that the quality of the extract that you choose is going to have an impact on the end result. The majority of home bakers are so accustomed to using the fake kind that they probably have never tried the real thing. Let me tell you, it is well worth the extra money.
Real vanilla extract
is made by marinating chopped vanilla beans in a mixture of alcohol and water, which is allowed to age for at least two years to get the maximum flavor. Each company has their own method of doing this, some use heat, others do not. Most use a special blend of vanilla beans from various parts of the world to create their own special flavor blend. You might want to try a few different types to decide which one you prefer, flavor-wise.
The minimum alcohol level in a vanilla extract is 35%, though some will go over this to ensure top flavor and preservation. The more expensive the extract, the higher quality the beans used to make it. You really do get what you pay for in this case!
Essentially what you want is an extract that has aged naturally and in coolness, with no unnecessary additives such as sugar or chemicals. The purest vanilla extract will give an extra kick to everything you use it in and the difference really is noticeable.