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Tuesday, July 15, 2014

Making Good Wine: The Harvest

In this part of the world harvest or Vintage as it is named predominately occurs after December. There are some varieties which ripen earlier or are picked earlier because the natural acidity is needed for making sparkling wine. But lets stick with ordinary still wine making and in particular the Chambourcin in HHF's vineyard. The harvest of other varieties made at HHF is almost entirely controlled by the vineyards where we source those. We pick when they pick to co-ordinate with their pickers or machines.

Deciding on a picking date centres around the degree of ripeness. This involves wandering around the vineyard selecting individual grapes from different locations and different positions on the bunch. These berries are squeezed onto a refractometer to measure the sugar content. An alternative is to collect all the berries and squash them together to get an average. In a small vineyard there just isn't enough bunches to spare to collect whole bunches and perform a more thorough Specific Gravity test. Experience over a number of years has proven that the refractometer test is always at least 1  degrees higher than reality. This is kept in mind when weighing up picking times.

The thing about nature is that it is never even. The grapes from the eastern side are usually not as ripe as the western side. The grapes higher up the slope are riper than the grapes in the hollow. A nearby tar road radiates heat to ripen the bunches on that side. Every little variation in soil, aspect and influencing structure modifies the rate of maturity. And there is no way of knowing, until after harvest, of how many vines were influenced by any one variation. It is all a rough guess and experience.

The second test for ripeness is the taste test. This is a good test for overall flavour i.e. skin ripeness. The good wine makers base their decisions as much on this as any thing else.

The other useful test of maturity is the grape seed. Brown indicates ripeness, green says it's probably too early.

Acidity reduces as sugar levels increase. In ideal ripening years the two come together in perfect balance but this is a rare phenomenon. Although it's wonderful to have the balance naturally, insufficient acidity and high pH can be handled after harvest without making the end product suffer.

At HHF picking is based on when the fruit has truly ripened i.e. the seeds have started browning. This seems to be about the best indication that nature's work is at an end.

Weather sometimes dictates activity as well. If the grapes are close to ripeness and the weather report says 90% chance 150 mm of rain in the next week there are only a couple of options. Take a chance, harvest or place a bet each way and harvest 50% as a precaution. It really depends on how important it is to have some wine as opposed to possibly none. Sometimes it is better to go without rather than make an inferior product.

Picking is best done in the early morning cool. The grapes are cold and less likely to commence premature fermentation with wild yeasts. It is also more pleasant picking in the coolness of the morning than the middle of the day.

Even for the amateur weighing the harvest is important as it allows calculations to be easily performed in advance for things such fermentation vessel size, finishing vessel size, calculations for Potassium Metabisulphite etc. It is a short step from Kilograms to litres. In the HHF Vintage book the yield of liquid in litres is recorded against every wine. These yields are amazingly consistent. They vary a little in dry years. On average the yields are close to 60% at pressing time.

Our preferred picking container is an upright 100 litre plastic drum because it keeps the mouth of the drum close to the bunches for cutting and dropping and it facilitates moving the container without having to bend over.

The best implement is a small pair of scissors with a plastic handle to prevent blisters. It is light and requires minimum pressure to severe the stem. The short pointy cutting blades make it easy to position the blades for cutting.

One of the most important tasks is not speed but quality. Each bunch is examined and any bad fruit removed. Bad fruit being dry rock hard berries, bird picked berries, rotten berries and green unripe berries. Shrivelled raisin like berries are fine. And absolutely no leaves in the bin.

Chambourcin fruit is easy to pick with its long stem and large bunches.  Some varieties such as Malbec, Chardonnay and Traminer are really hard work with small secreted stems and tiny bunches. But then not all aspects of wine making are joyous activities.

Next: Making Good Wine: Fermentation Part One

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