The Port harvest season begins in the Douro in mid August, when we start weekly sampling of grapes from selected vineyards at each of Graham’s five quintas. As the second week’s samples were being analysed, we caught up with Charles Symington, Graham’s head winemaker, and Steve Rogerson, our research oenologist who has been managing the data collection for maturation studies for us for more than 10 years.
The news is pretty straightforward right now, with no real surprises:
- Overall, maturation is behind average, but we expected that, given that pintor (the change in grape colour from green to red) was almost two weeks later than average.
- The grapes are in good condition – also as expected, since the dry conditions this year have helped limit outbreaks of fungal disease.
- We expect lower than usual yields – no surprise, given the generally dry conditions and uneven fruit set this spring.
- Right now, indications are for a late start to harvest. Steve, comparing the data so far with statistical trends over the past 15 years, says that right now it looks as if it could be among the latest harvests we have had. Charles, based on gut instinct, experience, knowledge of the vineyards and optimism, thinks we are likely to catch up and start not much later than usual.
Faithful readers will recall that in early July Charles was wishing for a cooler than usual summer and a little rain in July and August. So far, his wish has been granted: we have hardly seen 40ºC this summer, and nights have been cool. We had useful amounts of rain at the end of July and again last week, the effects of which were reflected in this week’s grape samples, which showed a nice increase in sugars since the first samples were analysed.
There is no forecast of rain in the near future, but a little more before harvest would be welcome. We are also hoping for continued temperate (for the Douro!) conditions; a really hot spell could slow the maturation as photosynthesis and plant function shut down in periods of prolonged high heat.
About Maturation Studies
Maturation studies involve two processes to analyse the grapes and estimate the start of harvest based on their maturity. Just as highlighted in Charles’s and Steve’s different expectations for the likely start of harvest, one method is based on what we see, taste and know about our vineyards based on years of experience, and the other is based on rigorous scientific analysis. Both approaches have value and come to bear in the final decision making.
One process is simple and obvious: visiting the vineyards and tasting the grapes. From now through the end of harvest, Charles will spend a lot of time simply walking through the vineyards, looking at the state of the vines and tasting the grapes as he goes, to understand how the grapes are maturing and when we should begin our harvest. As we get closer to harvest, he will be joined by Graham’s winemaker Henry Shotton and viticulturist Alexandre Mariz at Malvedos and Tua, and together they will determine picking order based on the quality of the grapes.
The other process is based on the laboratory analysis of grape samples. Every week from mid August until harvest begins we gather 200 grapes from each designated parcel, and we sample several parcels of different grape varieties within each of our major vineyards. Samples are gathered from the same vineyards on the same days each week to ensure data integrity. For Graham’s, we gather samples from all five quintas since they are spread out across the region: Vale de Malhadas in the Douro Superior, Tua, Malvedos and Vila Velha are all on the river in the Cima Corgo, and Quinta das Lages which is in the Rio Torto Valley, south of the Douro near Pinhão.
In the lab, each 200 berry sample is weighed and then pressed, and the must from the press is centrifuged and the volume of liquid recorded. These tests, along with an average bunch count per vine, help us anticipate the yields for each variety and quinta. The must is poured into a glass and assessed visually for colour, then analysed for baumé (an indicator of sugars and probable alcohol) and acidity. Then we do a good old fashioned taste test and record our tasting notes.
An additional 100 berries is being collected from select parcels for additional research. These berries are being processed differently, with the lab team analysing the resulting must for levels of specific colour and flavour compounds as well as tannins.
Stay with us for updates on maturation studies, preparations for harvest and of course comprehensive coverage of the harvest and winemaking at Graham’s Quinta dos Malvedos.