The Ravoire & Fils company, trading at nearly 5 million bottles per year, has been closely examining oxygen management during bottling. Why? Because its goal is to preserve the quality of its wines, especially those under screwcap, like its rosés, and avoid uncontrolled oxygen additions to the bottle.
Identifying critical steps of oxygen pickup in wines through an audit
“For our rosé wines, our goal is to limit oxygen pickup to preserve their aroma and color as much as possible. We began with an audit to identify the critical points of dissolved oxygen pickup in our wines. The diagnosis was good in the cellar but at the bottling stage the oxygen pickup was high,” explains Julien Gaubert, Technical Director at Ravoire & Fils. The company then invested in state-of-the-art equipment that removes dissolved oxygen from the wine just before bottling, while readjusting dissolved carbon dioxide levels in the wines. To limit the dissolution of oxygen during filling, the company switched the way it dried the rinsed bottles, and moved from an air system to a nitrogen-based system. This allowed Ravoire & Fils to improve results in the wines after a few months in bottle, but they were still not completely satisfied.
Controlling dissolved oxygen at bottling is not enough
“By running analytical checks after bottling, we noticed that the free SO2 concentration was falling rapidly. Beyond the potential impact on aromatic preservation, the wine color was also changing. This is what alerted us to the gaseous oxygen present in the bottleneck headspace,” recalls Gaubert. With screwcaps, the headspace volume (the space between the wine and the closure) is larger and a higher source of oxygen in the bottle. “We looked for a system to control and limit gaseous oxygen pickup in the headspace. This led us to invest in the NomaLine HS6000 , a system that inerts with nitrogen both the bottle headspace and the inside of the screwcap just before capping. The important thing is to be able to control the inputs, which the system does. However, it is also important to be able to precisely measure the headspace oxygen and make sure the concentration is the one expected,” explains Gaubert. With this new system, the Ravoire & Fils company now has complete oxygen control solutions for screwcap bottling and has already seen improvement in its wines.