White residue on stylus

I have found that when i look at my lp under a 30x microscope i can see what looks like a clear liquid or maybe a crystal like substance in the grooves . This is in a very small area but there are a number of these throughout the album. The album has been cleaned 6 times using the following process with AIVS cleaning system.
Enzyeme formula ,light scrub and soak for 30 min. then steam and vacuum.
Super clean formula , light scrub soak for 30 min. and steam and vacuum.
I have repeated this 5 times, with an inspection with the 30x microscope each time. After each cleaning the lp is getting cleaner but the clear substance in the groove has only reduced by about 50% . On the last clean i lightly scrubbed for about 5 min which did reduce it a little more. I have noted the location of these deposits in relation to the label and i am able to view it after each cleaning to monitor the progress so far. I am sure the pops i here are these deposits.
I notice when i play the album i have a buildup of white powdery residue on the stylus that is easily brushed off or removed with a Magic eraser lollipop.

Does anyone know what these deposits are or what is the best way to remove them?

The albums are New old stock direct to disc that have been stored sealed for about 27 years.