italianoenglishfrançaisdeutschespañolportuguês
Language
Search
  • » News
  • » Yeast research discovers some sensitivities
  • Vicente Ferreira , LAAE, Universidad de Zaragoza
    VIDEO SEMINAR ENOFORUM 2018: 70% of commercial wines contain, without it being evident, the aromas that will cause their aromatic degradation when free SO2 level decreases. Essentially there are tw...
    Price:15 €(Tax included)
    Published on: 17/01/2019

Yeast research discovers some sensitivities

Yeast research discovers some sensitivities

The Australian Wine Research Institute’s (AWRI) commitment to better understanding the nature and behaviour of the wide range of yeasts available to winemakers is bearing fruit both scientifically and practically.

A project led by Dr Simon Schmidt has provided a comprehensive picture of the genomic makeup of 200 common strains and their relationship to each other, while also screening nearly half those yeasts for their tolerance or otherwise to a wide range of fermentation-relevant variables such as sulfite and nitrogen concentration in grape juice.

The project was built on the complex sequencing of the strains. The research team was interested in both the genetic diversity of the yeasts commonly used to make wine and the diversity of their behaviour.

While wine yeasts are quite different from those used in sake or bread making, for example, they form a fairly homogenous group. But within that group are some distinct sub-groups, a third of which relate to what are commonly called champagne yeasts.

What is surprising is that these genetic sub-groups don’t relate directly to what people use the yeasts for. There is no obvious relationship between an application such as red winemaking and the genetics of the yeast, although that doesn’t mean there aren’t some underlying traits that cluster together, such as in the group of ‘flavour enhancing yeasts’.

Having built this foundation, the researchers selected 94 strains for more intensive examination, picking representatives from across what they considered to be the entire diversity of wine yeasts.

By using molecular barcoding – inserting a DNA barcode into each yeast – they were then able to measure the performance of all 94 in a single ferment, comparing them in an identical environment and between environments.

‘The beauty of doing it the way we did was that because we didn’t have to deal with 94 individual yeast strains. We didn’t then have to test those 94 strains in each environmental condition that we wanted to test’, Dr Schmidt said. ‘We put them in the same flask and were able to untangle their individual performance characteristics afterwards.’

The researchers studied each yeast in relation to common things such as high sugar concentration and different temperature profiles, but what really stood out was copper and sulfite tolerance.

‘For many stresses the impact is similar for all yeasts, but copper and sulfite tolerance really heavily distinguish different yeast strains. Some are exquisitely sensitive to copper, which can be present in grapes from the soil or from vineyard sprays.’

 ‘What is interesting is that if a strain is copper tolerant it can’t really be sulfite tolerant and vice versa; it seems that the tools a yeast employs to become sulfite tolerant, for reasons that we don’t fully understand, make it copper sensitive. There’s a trade-off.’

Source: www.wineaustralia.com

Published on 13/02/2018
Item available in italiano francais spagnolo
Related sheets
  • Grapevines winter pruning
    In the context of Action 7 of the ValorinVitis Project, the first session of "school in the vineyard" for foreign refugees was held on March 13, 2018. The group of 15 refugees managed by the cooper...
    Published on:20/03/2018
  • The 2016 California winegrape harvest was early, with a mostly normal yield of exceptional quality fruit throughout the state. A relatively even growing season followed welcome winter rains that he...
    Published on:01/11/2016
  • The fifth edition of the International Grenaches du Monde Competition, launched in 2013 by the Conseil Interprofessionnel des Vins du Roussillon (CIVR – Interprofessional Board of Roussillon ...
    Published on:19/02/2017
  • Entries open in September 2016 and close on 28 February 2017.
    The OIV Awards rewards the best works published over the past two previous years which provide an original and relevant contribution, with an international significance for the vine and wine sector...
    Published on:23/08/2016
  • Grants offered within the framework of this programme are short term (six months to fifteen months maximum) and are provided for specific post graduate training programmes
    Published on:29/07/2017
  • Who is active, entertaining, educating the masses, and sharing on Twitter, Facebook, Instagram and the other platforms today?
    Published on:05/02/2017
© All Right Reserved
ISSN 1826-1590 VAT: IT01286830334
powered by Infonet Srl Piacenza
Privacy Policy
This website and its related third-party services make use of cookies necessary for the purposes described in the cookie policy. If you want to learn more about cookies or how to disable them (either totally or partially), please see the cookie policy. By closing this banner, scrolling through this page, clicking on a link or continuing navigation in any other way, you consent to the use of cookies.
More informationOK

- A +
ExecTime : 2,5625