What is chaptalisation? - ask Decanter

We explain what it means when wineries talk about chaptalising their wines.

What is chaptalisation? – ask Decanter

There are several winemaking processes that see sugar added in order to improve or stylistically alter the finished wine, in addition to the natural sugars found in grapes.

One such process is chaptalisation, named after its French originator Jean Antoine Chaptal.

Chaptalisation is where sucrose is added to grape juice prior to fermentation, in order to enrich the juice and achieve a higher level of potential alcohol.

Can you taste chaptalisation?

It typically doesn’t leave a lot of sweetness in the finished wine, because yeast will convert the sugar to alcohol. However, chaptalisation has been criticised for contributing to some wines lacking balance.

Cool climate regions

In cooler climate regions such as England, France, Germany and New Zealand, it can be common to chaptalise and especially in years when bad weather means that grapes could fully ripen. Acidity levels fall and sugar levels rise in grapes as they ripen.

Lyme Bay winery, England. Chaptalisation is practised in many cool climate regions. Credit: Lyme Bay Facebook

‘You want to do it as little as possible’

However, chaptalisation is strictly regulated. Germany does not allow it for Prädikatswein, for example, and it is banned in several countries, including Italy, Australia and South Africa.

‘You want to chaptalise as little as possible,’ says winemaker Liam Idzikowski from Lyme Bay Winery in Devon, south-west England.

‘When you add sugar you’re diluting the wine, essentially, so for every kilogram of sugar you add, you get 0.66 litres of extra wine that hasn’t got any flavour at all.’

At Lyme Bay, Idzikowski aims for 10%-10.5% potential alcohol in the grapes at harvest, and will chaptalise to get it up to this level if there’s a shortage of sugar in the grapes at the time of picking.