A Harvest Visit to Château du Val d’Or, 2012: Machine Sorting
Clambering up the step metal steps to the top of the sorting machine afforded me a good view of the newly-picked fruit within the stainless steel hoppers. These berries are machine picked, so naturally I was expecting to see a mush of bruised and damaged fruit. But that certainly wasn’t the case; what I found atop the machine were two mounds of fruit, the ripe berries glistening black in the Bordeaux sunshine, whole, plump and as far as I could see undamaged. Sure, there were a few damaged berries here and there – that was why the fruit was going through this new and noisy sorting machine, after all – but on the whole the fruit looked very healthy indeed. Good enough to eat, in fact. Or, ultimately, drink.
The machine on which I was standing is about the size of two modern agricultural tractors, parked end to end, and perhaps the same height. Its purpose is to sort the fruit, rejecting not only damaged but also unripe berries, before separating out the healthy survivors according to size. Thus there are three principle mechanisms involved, the first being the removal of damaged fruit. This is achieved immediately the berries fall from the hopper, as they land on a rotating drum. Healthy intact berries bounce off to one side, ready for stage two of the sorting process. Those berries that are damaged, however, land with a splat on the drum, and adhere to it rather than bouncing off. As a result they travel on the drum for half a revolution, away from the vat that takes the healthy, bouncy fruit, before being scraped off into a disposal bin. The survivors, having passed the first test, now find themselves in a bath of must, grape juice with a controlled concentration of sugar. This concentration is set by Philippe in order to differentiate between ripe and unripe berries. Those berries with a higher sugar concentration than that in the juice have sufficient density to sink, and have passed the test. The unripe berries float and are thus siphoned off into disposal bin number two. Clearly the ‘ripeness’ on which the fruit is sorted is sugar concentration rather than physiological ripeness, nevertheless the method certainly has validity; tasting rejected fruit against accepted fruit reveals a tangible difference in sweetness.
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