Twelve weeks of maceration complete. The formula has been evaluated at 72 hours, 4 weeks, and 8 weeks. It is ready for filtration. This is not a cosmetic step — it is the final stability confirmation before the formula is sealed into a bottle for good.

Filtration after maceration serves a different purpose from the −89°C chill before it. The chill removed the compounds that would never be stable in the formula. Filtration after maceration removes any fine particulate that has formed during the 12-week integration process — residual wax traces, microscopic precipitates from the fixative system's interaction with the concentrate, and any other matter that has separated from the solution during maceration. The filtered formula is clear, bright, and stable. Clarity is not an aesthetic goal. It is evidence that the formula is chemically complete and will not change, cloud, or degrade in the bottle.

WHAT WE DID

Post-maceration filtration uses a fine filter medium — typically 1 micron — through which the formula is passed at controlled temperature. The filtered batch then enters a 48-hour stability hold at ambient room temperature. The purpose: to confirm that the formula remains clear once it returns to the conditions in which it will be stored and used. A formula that clouds or precipitates during the stability hold requires further filtration. A formula that passes the stability hold — clear at 48 hours at room temperature — is confirmed stable and approved for hand-bottling. The stability hold is not optional.

WHAT COMES NEXT

Hand-bottling in London — the filtered, stable formula is filled into bottles by hand, sealed, and labelled. This is the final stage of the batch process.