What is my tincture strength?

by Rob
(Portugal)

Question:

We have been making Olive Leave Extract recently. Looks like it is good. We base it on 40% alcohol.
2 Questions:
- How fine do you cut the leaves? We cut it with a knife and scissors. Do you cut with a grinder?
- We do not know how much mg oleuropein is contained in 2,5 ml of the extract? Do you know roughly how much this contains?

Answer:

You can cut the leaves very finely or shred them in a food processor with a little of the alcohol.
You want to draw as much out of the cells as possible so the finer the better.

I had the same question about strength from a previous visitor.
You need to know the dry weight of leaves used and the volume of alcohol.
In this case it was 4oz of leaves in 8oz of vodka.

Good quality dried leaves contain about 2-4% by weight of oleuropein.
Lets assume you got most of the oleuropein out of the leaves.

You have 4oz =113g of leaves. At 4% you will have about 113x0.04 = 4,52g oleuropein.
You use 8oz (226g or very roughly 226ml) of Vodka.

You have 4,52g x 1000 = 4520mg oleuropein in your whole bottle of tincture.
As you won't drink the leaves, and the oleuropein is dissolved, you have 4520g/226ml of tincture which equates to 20mg/ml.(which is quite a good strength).

This is obviously very rule-of-thumb, but there are other actives in the olive leaf so the overall effect should be about equivalent.