Strange Bitterness

[abrewer2]

I first noticed this a couple of months ago in a commercial beer but now this sensation has come up in a friends IPA and I need help trying to figure it out. You take a drink, hop presence and bitterness fade away completely in a few seconds, you wait about 5 to 10 seconds and a bitterness in your mouth comes back again. It's strange. My friend has been brewing for quite a few years and has sound procedures. Any thoughts?

 

[ricshayne]

Just like in wine beer has a finish that will linger on your palate even after you have swallowed the sip. sounds perfectly alright to me and your friend shouldn't be too concerned

 

[abrewer2]

What is so odd about this sensation is it doesn't seem to linger, but the hop bitterness goes away then seems to have a second bitter sensation.