Manual vs. mechanic. Controversies and facts
Up until 20 years ago, mechanical harvesting had an unfortunate reputation. From picking all the grapes, without discrimination, to the remnants of leaves and even strings that arrived with the grapes at the destemming stage, a number of possible disadvantages had to be considered upon harvesting grapes with combine harvesters, all these unwanted “ingredients” affecting the taste of the stum.
Today, however, the technology has advanced so much that extremely fine adjustments can be made, so that the harvesting is done practically grape by grape, being selected only the ones that have reached the exact level of maturity desired by the oenologist. A well-made adjustment ensures that the grapes affected by rot or the too green ones with an insufficient sugar content, are not harvested.
Another drawback of the mechanical harvesting is that stum would form during the gathering of the grains in the dump bin, which would lead (by oxidation or souring) to the damage of the grapes and, implicitly, of the stum in the press. Again, this is according to the technology type used. The two harvesting combines used at Domeniul Coroanei Segarcea collect 5 tons of grapes in half an hour and they subsequently reach the winery in just a few minutes, insufficient time for the stum to oxidize or sour. Instead, when picked manually, even when using crates, harvesting an equal amount would take at least three hours (even longer at night) and any stum (which is inevitable), even if it were a significantly smaller amount, would already be oxidized by the time the grapes reach the cellar.
But the overwhelming advantage of technology is not only the speed, but especially the fact that, once the adjustments are made, harvesting can be done at night, which is a fundamental element for keeping the flavours intact throughout the process, from picking to pressing. Harvested during the day, grapes can lose up to 25% of their aromatic components just because they have spent too much time in crates/dump bins. Moreover, human error in picking at night occurs much more often than in mechanized harvesting – sometimes you only have to distinguish between subtle shades of green or yellow, which is difficult in the light of flashlights or spotlights. Finally, with the widespread loss of labour in agriculture, even if we find enough resources for harvesting in the morning and evening (to avoid the hot hours, in which, as I wrote above, flavours are lost), finding people to work at night is downright impossible.
Obviously, technology is an answer for absolutely all situations. At Domeniul coroanei Segarcea, I discovered after almost 20 years of continuous work, that the ideal recipe is to use people where they are needed and to complete their work with that of machinery.
For example, in some varieties we have had sour grapes for several years – the second grape of the year, which can be very similar to the first grapes, but never reach the same quality and the same concentration of sugars as normal grapes. The sour grapes are cut off by hand and left on the ground, together with other insufficiently ripen grapes, just a few days before harvest, so that there is no risk of them reaching the stum.
Obviously, for some varieties or for some special wines, the harvest can only be done manually. A simple example consists of the Tămâioasă Roză grapes for the semi-sweet wine, which are harvested when they begin to wither. Given that not all grapes reach the same maturity at exactly the same time, these plots are traversed several times (usually three times) and only the grapes that have reached their withering stage are harvested by hand.
In conclusion, manual harvesting can be, under certain conditions – night, professionalism, large workforce – the desired solution, especially for small areas in which the grapes to be harvested can even be marked during the day. Upon larger areas, however, mechanical picking at night has many more advantages than disadvantages. But only when investing in technology without restraint, without looking for the cheapest option and only using this technology, bearing in mind the concern for quality wines. Otherwise, yes, those who are afraid of branches and leaves reaching the press, they have a right for concern…