Looking around the web there seems to be a lot of mention of the use of the iodine (starch) test at the end of your mash. Is it actually useful (i.e. is it reliable)? There have been times when I have done the test and it has continually returned a residual starch presence in my mash, even after having mashed for 60-90 minutes at the appropriate temperatures/mash thickness etc.
Is there some other test one can do, or do we just mash on ahead regardless?