scottreiner
scott reiner
phew! i'm in the clear. i believe they are coming out with an extended skin time, anfora fermented chard next year!!! they're going to call it pie, maybe some rs...
My frenemy, Brett
- Thread starter Sharon Bowman
- Start date
phew! i'm in the clear. i believe they are coming out with an extended skin time, anfora fermented chard next year!!! they're going to call it pie, maybe some rs...
nigel groundwater
nigel groundwater
I apologise for the length of what follows, particularly if it is all already well understood.
As mentioned the main control for brett is SO2 usage throughout the winemaking process along with other procedures to remove/limit/exclude brett from inhabiting old and new barrels [it loves the sugars in new wood] and other winery facilities.
Dimethyl dicarbonate [aka Velcorin or DMDC] which is widely used in the USA and has more recently been approved for use in Europe] is a sterilant which deals with brett and other spoilage mechanisms. DMDC is dangerous in use requiring expensive equipment but is safe in wine.
Sterile filtration is also effective in preventing any further brett and other spoilage development in bottle but is also accused of reducing/removing the natural [good] flavour of wine and therefore often excluded or limited along with SO2 by [particularly natural] winemakers. DMDC is claimed to make sterile filtration unnecessary and to therefore provide a superior, more natural product but, as another chemical intervention, can be eschewed by the natural brigade for that reason.
The trend to using riper grapes [directionally more sugar, lower acidity and higher alcohol] and more natural winemaking with lower SO2 usage and no or low filtration can all be positive direct and indirect contributors to the success of the brettanomyces yeast with e.g. low acidity reducing the effectiveness of SO2 and higher alcohol increasing the incidence of the use of diammonium phosphate [DAP] to avoid or resolve stuck fermentations as well as increasing the possibility of significant residual sugar in the final product which provides for the potential for further development in the bottle if any live yeast cells remain.
In summary, positive factors for brettanomyces include high sugar levels, low acidity, oxygen [micro-oxygenation has been reported as both a plus and a minus] and stuck fermentations [when brettanomyces can assert itself] due to higher alcohol from the higher sugars in riper grapes. DAP used to deal with or prevent stuck fermentations can perversely act as an alternative/additional brett feedstock.
Temperature is also a factor and if brett and the necessary feedstocks are still present after bottling, any live brett yeast cells can continue to produce the phenols and fatty acids during transportation and in storage at higher than ideal temperatures [less than 14oC says Lapierre for his no-sulphur Morgons] and can bloom in the bottle.
This, in addition to very different individual sensitivities, can explain why the same wine from different bottles at different times can provoke such variable brett experiences and comments. Of course the wine might come from different production lots at the winery which could also cause major differences in the level of brett products in the bottled wine.
Pegau Reservee 98 has been mentioned several times in this thread but IIRC comments over many years about Pegau 99 particularly in the USA have been much more numerous. A key explanation would appear to have been that there were certainly at least 2 different lots exported to the USA and that the brett populations were probably very different between the two and transportation and storage temperature differences might well have exacerbated the underlying differences still further.
Chateauneuf du Pape wines are often held up as the poster children for brett but the wild brettanomyces yeasts are widely present worldwide and most red wines anywhere [white are much less susceptible for reasons of higher acidities and generally more SO2 et al] can be affected depending on the constitution of the raw materials and how the wine is made, bottled and stored.
As mentioned the main control for brett is SO2 usage throughout the winemaking process along with other procedures to remove/limit/exclude brett from inhabiting old and new barrels [it loves the sugars in new wood] and other winery facilities.
Dimethyl dicarbonate [aka Velcorin or DMDC] which is widely used in the USA and has more recently been approved for use in Europe] is a sterilant which deals with brett and other spoilage mechanisms. DMDC is dangerous in use requiring expensive equipment but is safe in wine.
Sterile filtration is also effective in preventing any further brett and other spoilage development in bottle but is also accused of reducing/removing the natural [good] flavour of wine and therefore often excluded or limited along with SO2 by [particularly natural] winemakers. DMDC is claimed to make sterile filtration unnecessary and to therefore provide a superior, more natural product but, as another chemical intervention, can be eschewed by the natural brigade for that reason.
The trend to using riper grapes [directionally more sugar, lower acidity and higher alcohol] and more natural winemaking with lower SO2 usage and no or low filtration can all be positive direct and indirect contributors to the success of the brettanomyces yeast with e.g. low acidity reducing the effectiveness of SO2 and higher alcohol increasing the incidence of the use of diammonium phosphate [DAP] to avoid or resolve stuck fermentations as well as increasing the possibility of significant residual sugar in the final product which provides for the potential for further development in the bottle if any live yeast cells remain.
In summary, positive factors for brettanomyces include high sugar levels, low acidity, oxygen [micro-oxygenation has been reported as both a plus and a minus] and stuck fermentations [when brettanomyces can assert itself] due to higher alcohol from the higher sugars in riper grapes. DAP used to deal with or prevent stuck fermentations can perversely act as an alternative/additional brett feedstock.
Temperature is also a factor and if brett and the necessary feedstocks are still present after bottling, any live brett yeast cells can continue to produce the phenols and fatty acids during transportation and in storage at higher than ideal temperatures [less than 14oC says Lapierre for his no-sulphur Morgons] and can bloom in the bottle.
This, in addition to very different individual sensitivities, can explain why the same wine from different bottles at different times can provoke such variable brett experiences and comments. Of course the wine might come from different production lots at the winery which could also cause major differences in the level of brett products in the bottled wine.
Pegau Reservee 98 has been mentioned several times in this thread but IIRC comments over many years about Pegau 99 particularly in the USA have been much more numerous. A key explanation would appear to have been that there were certainly at least 2 different lots exported to the USA and that the brett populations were probably very different between the two and transportation and storage temperature differences might well have exacerbated the underlying differences still further.
Chateauneuf du Pape wines are often held up as the poster children for brett but the wild brettanomyces yeasts are widely present worldwide and most red wines anywhere [white are much less susceptible for reasons of higher acidities and generally more SO2 et al] can be affected depending on the constitution of the raw materials and how the wine is made, bottled and stored.
Hank Beckmeyer
Hank Beckmeyer
part of the awesome hip hop group of the 80's, no?
The Wine Mule
Dave Erickson
Thanks, Nigel.
Hank Beckmeyer
Hank Beckmeyer
a group of doctors from northern Michigan?