February – Hurry up and wait

01

Feb

February – Hurry up and wait

General

The secret in deciding when to start harvesting the grapes lie in the sugar.  The sugar levels have to be at exactly the right level to ensure that all the effort you’ve put into the maturing of the grapes translates into the quality of wines you have envisioned.

Grape maturity at harvest is critical for fermentation, perceptible sweetness and alcohol. The Brix scale was developed for this very reason. Brix is a measurement of the sugar content of grapes, indicating the degree of the ripeness (meaning sugar level) at harvest. Most table-wine grapes are harvested at between 21 and 25 Brix. To get an alcohol conversion level, you can multiply the stated Brix by .55 for a rough estimate. Vineyard managers use the Brix scale to monitor sugar development and concentration to determine the date of harvest. But just to add to the fun of the unknown – not all blocks will ripen at the same time, sometimes days can go by without any harvesting taking place.

But just as you call in the troops to start the harvest there is always the possibility of an unforeseen rain storm, resulting in the berries slurping up all that gorgeous water getting nice and round and big. So, what is the problem? Bigger berries = bigger yield right, that can’t be bad…  Nope, the berries have just gone and diluted the sugars it kept hidden and now the whole process have to wait until the grapes have gotten rid of the excess water.

On the farm

On Kersfontien we prefer our grapes to be closer to the upper levels on the Brix scale before harvesting.  This ensures that the skins and pips of the grapes have reached a level of ripeness that will result in softer tannins in the wines.  The flipside of this is the potential for higher alcohol levels due to the higher sugars but that is something that can be managed down the line.

During harvest time, our viniculturist (fancy word for our esteemed farm manager) will wake up at 1 am(!) to start the harvest.  He needs to get the teams ready for the handpicking and set up the mechanical harvester for the rest of the vineyards.  All of our premier wines are handpicked as well as the older blocks that have not been designed with mechanics in mind.  Harvesting stops mid-morning when the sun heats the vineyard and the sugar levels become unstable.  Nighttime harvesting ensures the consistent and controlled grape temperature needed for making wines.

If you are squeamish please stop reading now…  Last chance…   With the mechanical harvester, everything gets shaken off the vines, literally everything.  That means snails, lizards and even the odd snake all gets chucked into one big bin before it gets crushed – everything, together.  The advantage is that our wines are now officially banting friendly with all the added protein.

In the cellar

With all the efforts focused on the harvest the cellar takes a bit of a back seat.  All of the pre-used barrels get cleaned out and treated with dry ice to kill off any nasties that might have been left behind from the previous wines.  New barrels arrive (you always want a good mix between old and new barrels to give you a bit more of variety when blending the wines) and are given their spot in the cellar – ready to be filled with awesome goodness.

New words:

Millerandage:  When you have uneven ripening of grapes on a vine when you harvest.  It can produce wines that may smell sweet but that taste unbalanced, unripe or, “green.”

Brix:  The scale developed for measuring the sugar levels in grapes.

 

Good reading:

https://www.mirabeauwine.com/grapes-harvested-night/

http://www.calwineries.com/learn/wine-chemistry/sugar-in-wine/brix-scale

AUTHOR

Tanya Liebenberg

All stories by: Tanya Liebenberg