That is incorrect. I (and many others) have used pectin for cigar glue for years. To my jaded tongue, it has zero taste. If you apply too much, it just takes a long time to dry, and doesn't burn well. By applying only a sheen of viscous pectin to just the margin of the wrapper near the head, prior to finishing the wrap, it will dry quickly, and has no taste.
I recommend pectin because it adds no taste.
If pectin were bitter, then a whole bag of it, mixed into a batch of home-made jam, would make bitter jam. That having been said, some individual are uniquely capable of tasting certain things that most of the population cannot taste. I don't know that pectin is one of them, but I couldn't say for sure.
Bitter test: Lick your fingertip, then gently touch it to the surface of some dried pectin--not a gob of it, but just a dusting. Now touch it to your tongue.
Plan B: You can always try gum Arabic, gum Tragacanth, guar gum, or any other non-toxic gum.
Bob