At Pyramid Valley, our winemaking approach is about working alongside nature to allow the resulting wine to speak of its place. When it comes to Chardonnay, especially from our cool-climate Waikari vineyard, we face a unique challenge in the form of our naturally low pH and high acidity.
When dealing with Chardonnay from warmer regions, it's common practice to make a press cut to retain good acidity and tension in the wine. A press cut involves separating the pressings from the free-run juice, where typically, the first 550L/tonne is reserved for premium wine, and the last 100-150L/tonne is declassified to a lower tier.
At our Waikari site, we face a different challenge. Due to our cool climate and limestone-clay soils, we often harvest Chardonnay with very low pH, frequently below 3, and high total acidity around 12. This gives our wines their signature energy and vibrancy, but also presents a challenge in the cellar: how do we balance this naturally high acidity?
To do this, we use malolactic fermentation (MLF). This is a natural process where lactic acid bacteria converts the sharper malic acid into the softer lactic acid, lowering overall acidity and raising the pH, resulting in a more balanced wine.
At Pyramid Valley, we prefer to avoid these interventions and instead focus on what the grape itself naturally offers – the skins of these Chardonnay grapes. Grape skins are rich in potassium, which, when the juice is left in contact with the skins, increases the pH. This explains why skin-fermented wines typically have higher pH and lower acidity compared to wines fermented without skin contact.
Using this understanding, when we encounter a Chardonnay with a pH below 3, we crush the grapes and allow for a few hours of skin contact to raise the pH above 3. In these cases, we also forgo the press cut, as the higher pH from the pressings becomes beneficial. This approach enables the wine to naturally undergo malolactic fermentation without complications, resulting in a balanced and expressive wine that truly reflects its terroir.
Huw Kinch
Winemaker and Estate Manager
Pyramid Valley
October 2024 celebrates the launch of the Pyramid Valley Botanicals Collection from the 2022 vintage. For more on our Field of Fire and Lion’s Tooth Chardonnay from our Waikari farm, and availability, click here.