Extraction ratio or standardisation: which to ask for
Both ways of declaring the concentration of an extract are legitimate, they describe different things and they are not convertible into each other. Picking the wrong one is paid for on the label or in the lab.
What a ratio says
A 10:1 extract means ten kilos of dried plant went in to get one kilo of extract out. It is a mass relationship of the process, and so it describes what was done, not what came out.
The practical consequence is that a ratio guarantees no active content. If the starting harvest was poor in the compound you care about, a 10:1 can fall below a 4:1 made with better raw material. The number describes the concentration of everything extractable, active included, but also of everything else.
Watch out for inflated ratios too: some declare 100:1 on materials where the real yield makes that figure impossible without adding a carrier. When a ratio sounds extraordinary, ask for the marker percentage.
What a standardisation says
An extract standardised to 95 % curcuminoids declares the destination: the lot is adjusted, measured with a defined method and certified at that figure. What varies is how much work it took to get there, not the result.
That is exactly the property a label in milligrams needs, or a dose-per-serving calculation, or a health registration. With a fixed value and its method, the number on the label can be derived and can be defended.
Why they do not convert
The question arrives every week: «how many to one is a 95 %?». There is no general equivalence, and anyone who gives you one is making it up.
The reason is that the ratio depends on the content of the starting raw material, which changes with the harvest, the soil, the altitude and the moment of collection. You can compute the equivalent ratio of one specific lot, with its analysis in hand. You cannot build a conversion table.
When a supplier offers «10:1, equivalent to 95 %», what they have done is add two claims that do not hold together.
When to use each
Ask for standardised when the label declares an amount of compound, when the dose has to fit a small format, when the product has to be registered, or when you are comparing suppliers: without a fixed value and a method, the comparison does not exist.
A ratio makes sense when what you want is the whole profile of the plant rather than one compound, in herbal tradition products where the formula is expressed as dried plant equivalent, or when the marker for that species is not well established and there is no accepted method to measure.
How to ask for it without ambiguity
The short form that leaves no gap: binomial name, plant part, marker, percentage, method and carrier. For example, «Curcuma longa, rhizome, 95 % total curcuminoids by HPLC (USP), no added carrier».
If you also need the dried plant equivalent for the label, ask for it as a separate figure, computed on the lot shipped and signed by the supplier. It is a perfectly computable number; what it is not is a substitute for standardisation.