Project Number: 2072-21000-055-012-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Aug 1, 2020
End Date: Oct 31, 2022
Develop techniques for mitigation of affected grape juices and wines using reverse osmosis and enzymatic treatment for the hydrolysis of glycosides and other precursor forms of smoke related compounds or combinations of the two techniques.
This project will evaluate the use of reverse osmosis and enzymatic treatment for mitigation of smoke related off aromas and flavors in affected juices and wines. Reverse osmosis has been used commercially for the reduction of off-aromas in wines, by creating a permeate containing the volatile aroma compounds and then passing the permeate through a carbon or resin bed to remove the offending compounds. Unfortunately, the reverse osmosis membranes used for this process only remove the “free” smoke related compounds, but not the glycosides or other precursor forms of these compounds, which are too large to pass across the membranes. Over time, these precursor forms can hydrolyze, releasing more of the free compounds, resulting in wines with smoke related aromas again. Research will focus on optimization of membrane selection for creating permeates containing glycosides of the smoke related compounds. Membranes with varying molecular weight cut-off (MWCO) values would be tested to determine an appropriate MWCO for optimal transfer of precursors to the permeate. Wines generated from smoke exposure trials as well as commercial smoke affected wines, if available, will be used as test materials. Several commercial enzyme preparations have been identified which could be used to hydrolyze glycosides in the permeates, however, additional characterization of these enzyme preparations would be necessary to optimize the hydrolysis step.