It is common to associate ripeness with warm climates. But there is more nuance to this relationship between heat and ripeness than is commonly assumed. One thing I’ve noticed, when I periodically delve into old world wines, is that while warm regions seem to require alcohol at 14% or above to get their grapes ripe, cooler regions, and some winemakers in California who pick early, get ripe flavors with much less alcohol. (By ripe flavors, I don’t mean raisin notes. I mean rich, clear, focused fruit flavors.)
I suspect this has to do with the fact that vines start to shut down as the temperatures approach 90 degrees. After that point, the vines produce more sugar but not more flavor. Thus, a lot of that heat in warm climate regions is “wasted” when it comes to flavor. It just produces more sugar and potential alcohol.
There is also evidence that alcohol depresses floral and fruit aromas in wine while increasing wood and spice notes.
So why do we call riper, higher alcohol wines fruit bombs and why do consumers seem to gravitate toward them? I suspect there are at least three factors:
(1) Higher alcohol reduces the perception of sourness.
(2) Consumers like some sweetness in their wine which ripeness makes possible. Alcohol also directly contributes to sensations of sweetness at least for some people. This enhanced sweetness is interpreted as fruity by the brain unless the taster is skilled at distinguishing sugar from fruitiness.
(3) Alcohol and residual sugar contributes to a lush, full mouthfeel.
None of this is really about fruit or flavor. It’s about sugar or perceptions of sweetness and texture—sugar bombs not fruit bombs.