Beer Forum

There are several exact definitions of a "drop":

* the "metric" drop, 1/20 mL (50 μL).
* the medical drop, 1/12 mL (83⅓ μL).
* the Imperial drop, 1/36 of a fluidram (1/288 of an Imperial fluid ounce, or 1/1440 of a gill) (approximately 99 μL).
* an alternate, possibly apocryphal, definition of the drop is 1/1824 of a gill (approximately 78 μL).
* the U.S. drop, 1/60 of a US fluidram, 1/80 of a teaspoon or 1/480 of a U.S. fluid ounce (approximately 62 μL).
* an alternate definition of the U.S. drop is 1/96 of a teaspoon or 1/576 US fl oz (approximately 51 μL).

A drop can also be used less formally as a unit of volume in recipes. According to some older kitchen references, 24 drops = ¼ teaspoon. Using U.S. definitions, this makes the drop equal to about 0.051 mL, making it quite comparable to the pharmacist's drop.[3]

brewerTristan wrote:I'm wondering what the appropriate amount (in general) of vodka tincture is for 5 gallons? I brewed up an amber ale with sweet potatoes and made a spice tincture in 4 oz of vodka. How much of the vodka should I add to the keg? I think I've heard as little as 1/2 oz, but don't remember where. I drew a sample today and added about two drops to the glass and that seemed pleasant. No idea how to scale up from that!