Topic summary
Lyophilisation and why the cake looks the way it does
This is a generated summary. It shows the 5 most-liked posts from a topic of 38, in their original order, with the accepted answer included where one exists. It is a reading aid and it will miss nuance — the full topic is the record.
Residual moisture in a lyophilised product is a stability determinant and is measured by Karl Fischer titration. Above a few per cent, shelf life shortens considerably.
The step people skip is the one I have spelled out.
32 likes 12mo
desiccant_notes, post #1: Posting this under the heading it deserves: Lyophilisation and why the cake looks the way it does Everything below is what sits behind that. I was wrong about lyophilisation in a thread last spring and I would like to correct it publicly rather than quietly. The error was in the units, which changed the conclusion by an order of… Go to post
Adding the measurement that post #12 says would settle it.
Small correction to my own earlier position on lyophilisation. I had the units the wrong way round, which changes the conclusion by an order of magnitude and therefore changes it entirely.
isotonic_review, post #6: Post #2 put the caveat in the right place and I want to underline it. A collapsed cake indicates the product warmed above its collapse temperature during drying. It is not necessarily a quality failure and it is a real observation about the process. Genuinely open to being wrong about this one. Go to post
Lyophilisation was covered in the wiki last year and the page has a review date on it, which is a better starting point than my memory of a thread.
j.moreau, post #30: That reframing is the whole thing. The facts I already had. Go to post
Reporting rather than recommending, on lyophilisation. What happened is above. Whether it should have is a different question and not one I am qualified to answer.
Read the full topic (38 posts)
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