だと used similarly to
は but it also largely emphasises what's has come before it so that you can commented?
This is why I get a feeling of it meaning something along the lines of
"This flavour I'd assumed it would be until now has a certain (strong) emotional touch to it." - emphasising the fact that (unexpectedly) the flavour gives a strong emotional impression despite it being what they had assumed; please correct me if I'm wrong.