Grapes Ahoy!
This month we’ve been busy conducting crop estimations in the vineyard, as all four varieties; Pinot Noir, Chardonnay, Pinot Meunier and Pinot Gris have produced grapes this year. As the vines are only two years old, they are only producing a small amount of fruit; they are concentrating their energy on building up nutrient stores and growing a robust (deeper) root system.
To estimate the number of grapes we might harvest, we selected 50 vines at random and counted the number of bunches per vine. We then weighed random bunches and took the average of both, then multiplied it by the number of vines. This figure then needs to be increased by 1.5-2.0 times, because the bunches will gain in weight from now until when we pick them in late September/early October.
Currently the grapes are going through a process known as ‘verasion’, this is the where the formed berries are developing, the acidity levels within the grapes drop and sugar levels increase. As well as this, aroma compounds and polyphenols are developing within the grape, which give a wine it’s complexity.
Throughout the year, the vine captures energy via photosynthesis, it then stores the energy within its roots, then during version the energy gets transferred to the bunches.
To help promote sugar development, we have removed the leaves that surround the clusters of grapes, this also helps air flow around the fruit decreasing the risk of the bunches rotting.
We will need to watch out for birds, as the sugar levels rise in the grapes, they will become more appealing for them to munch on; fortunately, we have a large community of birds of prey living around the vineyard, therefore a lower number of grape eating birds.
When to pick
We will be measuring the sugar levels in the grapes on a regular basis using a refractometer. This measures the degree to which the light changes direction, called the angle of refraction due to the density of the juice (which is changed by the sugar levels). Each degree equates to one gram of sugar per one hundred grams of grape juice.
Skin Texture
Currently the skins of the under ripe grapes are thick, however, as they begin to ripen, they will become thinner and more delicate. This can be seen in the colour on the skins themselves moving from a rich green to a golden/black colour depending on the grape variety! It is possible to squeeze the grape and look for the skin slightly wrinkling, this is an indicator that the grapes are ripe.
Berry Tasty!
The best part, we will taste the berries themselves. We will need to take random samples from across each variety in the vineyard. We will then be looking for a balance of sugar and acid, with some evidence of flavours and aromas.
Seed Colour
The colour of the seed is a great indicator of ripeness, an under ripe grape will have a pale seed, however as the grapes begins to reach the optimal picking point, the seed will change from green to light brown.
Tannin Levels
Tannins are compounds found in the grape seeds, skins and stalks, they contribute to the structure and the mouthfeel of the wine. Typically, tannins are more prevalent in red grapes, but they also exist in white grapes. Young, unripe grapes will have harsh and astringent tannins, which create a drying or squeaky sensation in the mouth. When the grapes are ready to pick, the tannins will become more integrated and less harsh and bitter.
A lot can happen from now until harvest time, we are hoping for some sunny days, low wind levels and not too much rain – so if you have any tips to keep the rain at bay let us know! If all goes well, in the next few weeks our grapes will go off the winery and get turned into bottles of wine, ready for sale next spring. Our next blog will be all about our first harvest!