Now this is always a little bit of a compromise how fast you allow them to dissolve as the quicker they dissolve the greater the spread of attraction leaching out of the baits in the area being fished so personally I like them to slowly break away.
However not every one does so yes it is possible to slow the break down time.
I have used different things for this in the past but I guess the most readily available ingredient in most kitchens is good old plain flour.
Get a little on your fingers, scoop out a little paste then mould the plain flour into it. This should be enough to slow the break down time a little. Alternately Arrow Root or Egg Albumin can be used but if you really want to slow it down try corn flour.
Hope this perhaps helps others wanting to slow the break down time of their paste baits.