Vanilla Planifolia are 6 1/2" to 7" long. A 7 to 9 inch vanilla bean will weight approximately 5 grams and will yield about 1 gram or 1/2 teaspoon of vanillin seeds. Remember that the vanillin seeds are the essence and flavor of the vanilla, so it is important that the skin be as thin as possible. You want a "plump" bean with a thin skin; you want lots of seeds with little moisture . By gently squeezing the bean between your fingers, you can tell how thick or thin the bean is. When the seeds are scraped out, they should come off the skin easily, and no mush residue should be present. If you see so called "sugar crystals" coming out of the bean use them, do not discard the bean. They are pure vanillin crystals.