Most of the vanilla extract for kitchen use is one fold; for industrial use you go into 2, 3, 4 fold etc. To make one gallon of pure extract you need about 13.35 ounces of vanilla beans; to make 2 fold you need twice as much an so on, 35% alcohol and water (alcohol evaporates when you bake).
Vanilla extract should have no sugar, which not only gives a false impression of the product, but can also change the final flavor of the recipe; it is up to the chef to add sugar to the extract to enhance it or shoot up the flavor.
Vanilla extract should be sugarless when it arrives at the kitchen with nothing else added to it. The natural vanillin and other natural substances that make up the vanilla flavor are so complicated and difficult to imitate that nature needs no helping hand. The natural vanillin is sweet, fragrant and it helps preserve the bean. Pure vanilla extract is ageless; like a good cognac, time enhances its flavor and bouquet.