title: Aspartic acid protease from Botrytis cinerea removes haze-forming proteins during white winemaking.
abstract: White wines suffer from heat-induced protein hazes during transport and storage unless the proteins are removed prior to bottling. Bentonite fining is by far the most commonly used method, but it is inefficient and creates several other process challenges. An alternative to bentonite is the enzymatic removal of haze-forming grape pathogenesis-related proteins using added proteases. The major problem with this approach is that grape pathogenesis-related proteins are highly protease resistant unless they are heat denatured in combination with enzymatic treatment. This paper demonstrates that the protease BcAP8, from the grape fungal pathogen Botrytis cinerea , is capable of degrading chitinase, a major class of haze-forming proteins, without heat denaturation. Because BcAP8 effectively removes haze-forming proteins under normal winemaking conditions, it could potentially benefit winemakers by reducing bentonite requirements.
authors.affiliation: The Australian Wine Research Institute , P.O. Box 197, Glen Osmond, SA 5064, Australia.
authors.forename: Steven C
authors.initials: SC
authors.lastname: Van Sluyter
authors.forename: Nicholas I
authors.initials: NI
authors.lastname: Warnock
authors.forename: Simon
authors.initials: S
authors.lastname: Schmidt
authors.forename: Peter
authors.initials: P
authors.lastname: Anderson
authors.forename: Jan A L
authors.initials: JA
authors.lastname: van Kan
authors.forename: Antony
authors.initials: A
authors.lastname: Bacic
authors.forename: Elizabeth J
authors.initials: EJ
authors.lastname: Waters
mesh_terms: D057055:Aspartic Acid Proteases / Q000378:metabolism*; D020171:Botrytis / Q000201:enzymology*; D002688:Chitinases / Q000378:metabolism; D005285:Fermentation; D006358:Hot Temperature; D010940:Plant Proteins / Q000378:metabolism; D014176:Protein Biosynthesis; D027843:Vitis / Q000382:microbiology; D014920:Wine
chemical_list: D010940:Plant Proteins; D002688:Chitinases; D057055:Aspartic Acid Proteases