Stage 1 from Florence to Rimini certainly goes through (chianti) rufina, and perhaps past a few other chianti regions, whilst the run in to the finish goes within a km of the amazing San Patrignano project, so I might crack a bottle of their avi if I can find one in the wine fridge.
Stage 2 goes the reverse direction from coast to Bologna, also passing through Pianoro whose little truffle festival we so loved, and then through Rastignano where we were staying. As we cycled to the truffle festival, we can say we've ridden part of this year's route ourselves

Stage 3 probably holds the greatest interest, ending in Torino, but passing through two Barbaresco villages (Neive and Barbaresco itself) and passing some very well known vineyards. As well as that I'll be looking out for Corneliano d'Alba in the Roero wine region where we stayed before, and I even have a wine from there now.