(unredacted) text becomes image after redacting

Hi, 

I always run into trouble with the following operation: 
- I have an e-mail exchange in .pdf format. It is all searchable text. 

- I would like to take out some sensitive information. I do this by the Redact function, selecting all the sensitive text. I then "apply" the redaction. 

- The new file has the sensitive text correctly blacked out, but some pages are now images and not searchable anymore. Sometimes this concerns only a few pages in a long document, but now I had one example where it affected 2 out of 3 pages. 

- It is possible to run the OCR over that document, but it looks pixelled afterwards and the file size increases. Sometimes the OCR does not convert one or the other page. 

Is there some work-around?