Comparison of Juice Settling Techniques (Cold Settling vs Flotation) (2017)

This study examines the impact of different juice clarification techniques in Pinot Gris: cold settling vs flotation. Juice from the same lot of whole cluster-pressed grapes were split into two tanks, one for cold settling and one for flotation. The cold settled juice settled for one day, whereas the floated juice was clarified overnight. All other treatments between juices and wine were equal. The acidity dropped slightly for both treatments after clarification. The cold-settled wine had a slight lag before fermentation began compared to the float. There were no major wine chemistry differences between treatments. The cold-settled wine was slightly less cold stable and required slightly more bentonite to become heat stable. Overall, judges were not able to distinguish the wines from each other. There were no major preference trends for the wines. No strong sensory differences were present as well, except that cold settling may lower the perception of Body. These results suggest that flotation may be a beneficial technique not only to reduce turn-around time, enhance juice yield, and reduce chiller load; but that it may also serve as a mechanism for preserving aromatic intensity and fruit intensity similar to cold settling.

Read Full Report (PDF)