We harvested red grapes on Saturday 27th October, fairly late as Garnacha takes a long time to achieve phenolic ripeness. Late harvesting creates a problem: everyone else has picked up theirs, grapes left hanging are the only food available to birds… This time of year scarecrows and propane cannons are a must.
We collected ~400kgs of red grapes in the morning and processed them in the afternoon. The weather was on our side: dry at around 16C. Red wine fermentation is generally carried out somewhere between 20C and 30C. Managing temperature is a key factor on wine making. Lower temperatures help retain aromatic compounds (floral aromas and fruit flavours) on the must. Higher temperatures will achieve higher extraction of tannins, phenolics and colour (anthocyanins).
We macerate the must in a stainless steel tank at cellar temperature at around 17C. Fermentation at such cold temperature is slow and it takes the must 2 to 3 days to start in earnest. Sugar levels at 27Brix, 3.8 PH and 18C temperature. After the first 2-3 days, fermentation starts and both sugar levels and PH decrease slightly, temperature raises to 20C.
We do not add sulphur dioxide, just “biodynamic plus” grapes/grape must. Colour and tannin extraction seems to be working out well judging by the dark colour of the must. Phenolic ripeness might play a key role in the extraction of colour and tannins at low fermentation temperatures.
o edit.