The Rainwood blog · 10 notes
Field notes on botanical sourcing.
Practical notes from the people who prepare the specifications: how to read a COA, compare methods, assess contaminants, and qualify a supplier before the first purchase order.
How to use the blog
Start with the COA guide if you are evaluating certificates, or the supplier qualification checklist if you are evaluating a new source. The technical library has the definitions, methods, and regulatory references behind each note.
How to read a botanical extract COA without being fooled
A practical line-by-line guide to the certificate of analysis: what belongs on it, which numbers actually matter, and the shortcuts that should make you ask for more.
10:1 is not a strength: extract ratios versus standardization
What an extract ratio actually tells you, why a 10:1 powder can be weaker than a 4:1 extract, and how to write a specification that means something.
Heavy metals, pesticides, and solvents: the tests that decide clearance
A buyer's guide to the contaminant panel for botanical extracts, with practical limits, method notes, and the questions to ask before the first shipment.
HPLC or UV? Why two suppliers quote different numbers for the same extract
A plain-language explanation of the two assay methods behind most botanical extract specifications, and how to compare quotes fairly.
Your first botanical extract order: MOQ, samples, lead time, and documents
A practical timeline for a first purchase, from specification agreement to arrival, including the documents and checks that prevent expensive surprises.
Ashwagandha root vs root and leaf: the difference behind the same percentage
Two certificates can both say 5% withanolides and still describe different ingredients. A practical guide to plant part, label claims, and how to verify root-only ashwagandha.
Silymarin 80% by UV is not silybin 80% by HPLC
Milk thistle is one of the clearest examples of method-dependent specifications. Here is how to compare a UV silymarin figure with an HPLC silybin figure without being misled.
Beetroot powder is not a nitrate dose: comparing root powder, juice powder, and concentrate
Sports brands buy beetroot for nitrate, but labels often compare powder weight. A guide to the commercial forms, how nitrate is measured, and what to write in the specification.
Water-soluble curcumin: what to specify when a clear drink is the target
Standard 95% curcuminoids do not dissolve in water. A practical guide to dispersible and enhanced grades, how to test them, and what the specification should say.
How to qualify a botanical extract supplier: a 40-point checklist
A structured approach to supplier qualification: entity and facility, specification and methods, documents, traceability, change control, commercial terms, and the first order.
Technical library
The reference material behind the notes
Methods, regulations, terminology, and the documents buyers ask for.
Next step
A question the notes do not answer?
Send it with the extract and destination market. If the answer is useful to other buyers, it may become the next note.