Independent tannin analysis
A third-party lab measuring how much active persimmon tannin is actually in the finished bar. This is the number cheap bars cut and no competitor publishes.
The science & proof
The first persimmon soap built to be independently verified.
Every other brand in this category asks you to take their word for it. We're the only one putting our tannin content, fermentation, and sourcing through independent verification — and publishing it here as it completes.
Fermentation record
Written documentation of each stage of the kakishibu process our supplier uses, so 'fermented' is a record rather than a marketing word.
Full ingredient disclosure
The complete INCI list is on the product page today. No proprietary blends, no undisclosed fragrance.
01 — Lab verification
Independent tannin analysis
We submit our finished bar for third-party composition analysis to measure exactly how much active persimmon tannin it contains — the single thing cheap bars cut and no competitor will disclose.
- A measured concentration, not a number copied from a competitor
- Performed by an independent lab, not in-house
- Published in full on this page — including the method and the date
- Published even if the result is lower than we hoped
Composition Analysis
Not started
Pending
Independent tannin analysis — result publishes here on completion
- Testing body
- Not yet commissioned
- Method
- Third-party composition analysis
- Report ID
- Not yet issued
- Published
- On completion
We have not commissioned this test yet. When we do, the signed report will be embedded here and downloadable in full — including the result, whatever it turns out to be.
02 — Fermentation, documented
Traditional kakishibu, written down
The tannin only becomes effective through proper fermentation. We document each stage of the traditional kakishibu process — so "fermented" is a record you can read, not a word on a label.
1
Astringent persimmons selected
A high-tannin varietal, chosen for potency rather than cost.
2
Pressed and fermented
Fermented over months in the traditional kakishibu method — the step cheap bars skip.
3
Concentrated and stabilised
Tannin content concentrated so it survives being made into soap.
4
Finished bar measured
Composition analysis on the actual bar you receive, not on the raw extract.
Drop fermentation / persimmon process photo
03 — Sourcing transparency
You should know where the active comes from
Traceable extract origin, a full ingredient list, and no synthetic fragrance hiding a weak formula. Here's what goes in — and what stays out.
✓ What's in it
- Fermented Japanese persimmon (kakishibu) tannin extract
- Saponified olive, coconut and shea butter oils
- Green tea polyphenols
- Glycerin and water
✗ What's not
- Synthetic fragrance or masking agents
- Parabens
- Sulfates (SLS / SLES)
- Animal-derived ingredients or animal testing
◷ Origin
- Tannin extract: Japan
- Supplier documentation on file
- Full batch traceability
Our commitment to honesty
We'd rather show you a page marked "in progress" than a claim we can't back. As each report and document is finalized, it gets published right here — signed, dated, and downloadable. No human clinical trial has been conducted; "independently verified tannin content" refers to third-party composition analysis of the finished product.
Proof first. Then the purchase.
The only persimmon soap willing to show its work — backed by a 30-day money-back guarantee either way.