22Sep
2014

Romancing the Grapes: in Love with Mechanical Harvesters

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When most people think about grape harvest, this is what comes to mind. 

There is undoubtedly a charming, even romantic air about manual harvest, and when we buy a bottle of wine at the local store, this is how we like to imagine the grapes were picked.

Nevertheless, today, most harvesting is done by machine.

Why is it then, that when you ask a winery - known for high quality wines - how they harvest, most will answer that they pick all their grapes by hand, even though it may not be true? 

There still seems to be, in fact, a sort of “taboo” around the term “mechanical harvest”, and it may very well be true that in the mind of the consumer this practice is still associated with cheap, mass-produced supermarket wine.

We would like to confront this taboo once and for all, stating loud and clear that Avignonesi is PRO mechanical harvest.

Forget about old-time harvesters which brought in bruised grapes, twigs and vine leaves in one merry mixture. Forget about huge, difficult-to-manoeuvre machines which tear the branches of the vines, rip off the leaves and compress the soil. 

With today’s modern harvesters, mechanical grape harvesting is the most efficient method of removing grapes from the vines.

 

A harvester can either be self-propelled or towed by a tractor, depending on the type of vineyard it is meant to work in. At Avignonesi we have both kinds. The self-propelled machine is faster and easier to manoeuvre, but the towed harvester permits us to work in vineyards with narrow turning space.

Now, what actually happens when the harvester passes through a vineyard row?  As you can see on the attached film, a part of the harvester envelops or encases the vine, while it vibrates and strips the grapes directly off the stems with the use of linear, high-frequency rubber destemmers. The grapes fall off the vine and drop onto a conveyor belt, which also works as a sorting table, where a series of feeder rollers carry the grapes to the storage bins and evacuate all waste material such as the occasional wine leaf.

 

The towed harvester we test this year at Avignonesi is the Pellenc 8090SP (http://www.pellenc.com/agriculture/en/Machine-a-vendanger-tractee-serie-8090.aspx) It has a cleanliness rate of 99%.

The harvester has 2 relatively small storage bins (1500l each) which are emptied into a larger storage trailer which brings the grapes to the winery.

 

At the winery the grapes go through a two-step quality check before they are crushed and sent to vinification. They are first emptied onto a vibrating sorting table, where 4 people make sure that all non-healthy grapes are discarded. They then pass through the optical sorting machine Vistalys, where all grapes which do not conform to the encoded standard for a certain grape variety (shape, colour), are discarded.

Detractors of mechanical picking may say that the same result can easily be achieved through manual harvest, where the grapes are picked by the bunch and arrive at the winery in small cases. While this is true, there are many reasons for opting for mechanical harvest:

 

  1. Time is often of the essence in grape picking. With 200 ha/495 acres of vineyards to harvest, we often find ourselves running fast to get the grapes in house before a rainstorm or to harvest a large area of vineyards at just the right moment of maturation. With mechanical harvesters we can cover as much as 25 hectares/day (working 20 hours). As a comparison, our trained team of 25 vineyard workers can only cover 8 hectares/day (8 hour shift). We have found that there is a definite relation between grape quality and the ability to move fast.
     
  2. The cost of harvesting with machines is much lower than the cost of picking by hand. The use of harvesters enables us to keep the production cost lower which in the end reflects on the market price of our wines, to the advantage of the end consumer.
     
  3. With the global weather patterns changing, it becomes more and more rare to have a regular, weather-perfect vintage, where all the bunches on the vines are whole and healthy. Often we see both completely healthy, plump grapes and slightly dried grapes on the same bunch, and with manual harvest it is an exceedingly hard and expensive job to separate the damaged grapes from the healthy grapes on the bunch, before destemming. With mechanical harvest the grapes are destemmed directly by the harvester, which makes it easier to separate non-healthy grapes through the manual and optical selection process upon grape arrival at the winery.

 

To conclude, mechanical harvesters deserve much kudos. They may not be pretty, they may not be romantic, but they serve their purpose in ensuring a harvest management which is timely, cost-effective and quality minded. Better for us. Better for the consumer.

 

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