vinogodi ha scritto:non confondiamo il Brett con le riduzioni, anche forti
Eppure qualcuno si è preso la briga di fare analisi chimiche con i vini di Beaucastel, vi propongo una sintesi in Italiano e anche la parte dell'articolo originale
Un appassionato americano nel 1998 si è rotto di tutte le varie discussioni su Becaustel e il Brett e ha fatto analizzare una bottiglia di 1989 e una di 1990. Il risultato? Poche cellule di Brett ormai morte, ma livelli alti di 4-etilfenolo (Composto fenolico prodotto dal Brettanomyces): 897 microgrammi/litro per la 1989 e 3330 microgrammi/litro per la 1990.
E, aggiungo io, uno studio rileva che la soglia di percezione del 4-etilfenolo nel vino è di 725 microgrammi/litro
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https://onlinelibrary.wiley.com/doi/abs ... 2740620213)
Queste due cose dimostrano che si, nei vini di Beaucastel c'è stato l'intervento del Brett in fermentazione, che è anche percettibile all'uomo e che in alcune annate, come la 1990, a dei livelli anche decisamente alti.
Back in early 1998, Charles Collins, an American wine collector, became so frustrated with the endless wine geek discussions about Beaucastel and brett that he decided to find out for himself. He got hold of some scientific papers on the subject and read up about the subject. ‘I realised that the presence of the compound 4-ethyl-phenol is a virtually certain indicator of the presence of a brett infection’, recalls Collins. He contacted a lab who does testing for 4-ethyl-phenol and sent them some Beaucastel from his cellar. ‘I opted to test two of the most famous vintages, the 1989 and 1990’, Collins told me. ‘These wines are supposed to represent what great Beaucastel is all about.’ He prepared the samples for shipment in sterilized glass 375 ml bottles and used fresh corks to seal them. The wines were labelled so that the lab had no clue as to their identity.
The results? According to Collins, ‘they showed indisputable evidence that significant brett infections occurred in both the 1989 and 1990 vintages of Beaucastel.’ Microscan and plating tests showed only small amounts of mostly dead brett cells, but the 4-ethyl-phenol levels were 897 micrograms/litre for the 1989 and a whopping 3330 micrograms/litre for the 1990. Collins concludes, ‘if you personally like the smell of brett, then none of this should you dissuade you from buying and cellaring Beaucastel. You should, however, give up the myth that the odd flavours are due to terroir—they aren’t.’ I would add that while I’ve detected what I’ve always assumed, in the absence of data, to be high levels of brett in some vintages of Beaucastel—the 1991 springs to mind as one of the brettiest wines I’ve ever encountered—in vintages since the mid-1990s I haven’t encountered any. But, of course, unlike Collins, I haven’t done the lab tests that would be needed to verify this.
L'articolo poi riporta anche una testimonianza di Marc Perrin che dice "Il Brettanomyces non è un lievito che porta difetti come tanti pensano, ma semplicemente uno degli lieviti che esistono in enologia" e parla anche del ruolo che ha il Mourvèdre che contiene parecchi precursori del 4-etilfenolo e di come sarebbe possibile abbatterli attraverso l'uso di lieviti selezionati e solforosa in fermentazione, ma che si perderebbe il sapore e la tipicità.
‘We believe in natural winegrowing and winemaking, and I must admit that this has led us to have serious debates with scientists spanning three generations’, responds Beaucastel’s Marc Perrin. ‘In the mid-1950s, for instance, our grandfather, Jacques Perrin, decided to stop using chemical pesticides or herbicides on the vineyard. At that time, when scientists were recommending the use of such chemicals for productivity or lobby reasons, that seemed crazy and impossible. Now, it seems that people have changed their mind and more and more vineyards are turning organic. I could quote many more examples of opposition between a scientific vision of wine and our traditional/terroir oriented philosophy of wine, and the subject of Brettanomyces is just one more’, he explained. ‘There are certainly some Brettanomyces in every natural wine, because Brettanomyces is not a spoilage yeast (as many people think) but one of the yeasts that exist in winemaking. Some grapes, like Mourvèdre, are richer in 4-ethyl-phenol 'precursors' than others and we have a high percentage of these grapes in our vineyard. Of course, you can kill all natural yeasts, then use industrial yeast to start the fermentation, saturate the wine with SO2 and then strongly filtrate your wine. There will then be no remaining yeasts, but also no taste and no typicity. That is the difference between natural wine and industrial wine, between craftsmanship and mass-market product.’
http://www.wineanorak.com/brettanomyces.htm
) finché questo non spunta in maniera inaccettabile pregiudicando il bouquet.
,vale la pena?Grazie
!E,nn solo per lui.Nn penso avesse nessuna intenzione..recondita;voglio pensare che,come a parecchi su questa platea,il vino in questione..piacesse/veramente.Come detto sopra,ne ho preso..un paio di bocce.T' facc' sape' 