WINETECH Technical Yearbook 2020

bentonite it will most probably not phase out completely because many cellars have already adjusted their practices to limit the negative results thereof (Anonymous, 2019). REFERENCE Anonymous, 2019. Is it good night for bentonite? Australian and New Zealand Grapegrower and Winemaker , December 2019: 46.

of microporous size minerals consisting of hydrated aluminosilicates of sodium, potassium and barium. They can be read- ily dehydrated and hydrated. They are used as cation exchangers or for molecular separation and function in the same way as bentonite, but settle more effectively, which result in less lees losses than with bentonite. In spite of the potential alternatives for

on the receiving side of the membrane will most probably contain the proteins and the wine permeate, which will move through the membrane and will be protein stable. The challenge of this process involves the assurance that other wine components will not also be removed by the membrane and the protein removal is effective. Longer-term alternatives are still in an ear- lier stage and include magnetic nanoparti-

cles and zeolites. Nanoparticles are covered to make them selective for wine proteins, before being added to unstable wine. After a short interaction, an external magnet is used to remove the nanoparticles with the proteins to the tank bottom. A stable wine with limited lees is obtained. It has how- ever only been investigated on laboratory scale and its commercial feasibility must still be investigated. Zeolites are a group

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