Genetically modified yeast

I don't have blind faith, but I don't think they are completely unconcerned with public safety. I get to see how a lot of the sausage is made (so to speak), and at least at the major corporation I work for there's a lot of money & time invested in trying to do things the right way. Sure they don't get it right all the time, but it's not like they are trying to screw over humanity.

It's not as simple as all corporations are bad.

How about the production angle, David? Can you see any merit in that concern? I don't see a conspiracy theory there--I see a potential practical production situation with which winemakers may not want to deal.

Just trying to change the subject to an argument that has a chance at resolution!!!

[David M. Bueker]

It's not as simple as all corporations are bad.

Show me where I ever said anything even remotely resembling that.

Robin - you almost never remotely say anything in debates - you write in a world of implications to keep safe from ever having really said anything.

David B wrote;
I realized that one thing does bother me. It seems likely that the GM yeast is engineered to be more efficient. This would lead to even more alcohol in wines, potentially affecting their balance.

I don’t know, when it comes to producing alcohol-tolerant yeast strains nature by itself does a great job. I think in the laboratory, the researchers are more concerned with enhancement of aroma and flavor. Looking more to the genes that play a role in the production of flavor-related esters, aroma liberating enzymes and health antitoxidants.

Salute

Victor, yeasts to improve flavor and aroma may be in the pipeline but at the moment I believe only one GMO yeast, ML01, will be released this year. The purpose of ML01 is to make alcoholic and malolactic fermentations, normally a two-step process, occur at the same time.

[Robin Garr]

you almost never remotely say anything in debates - you write in a world of implications to keep safe from ever having really said anything.

Here's one: That is a frickin' lie.

[David M. Bueker]

That's fine Robin - I don't believe you, but I don't have to.

Amended to say that I am certainly overgeneralizing, but it's always very hard to pin you down to an actual opinion whenever there is debate. This one is no different from the debates on Parker, Scoring, etc.

Victor, yeasts to improve flavor and aroma may be in the pipeline but at the moment I believe only one GMO yeast, ML01, will be released this year. The purpose of ML01 is to make alcoholic and malolactic fermentations, normally a two-step process, occur at the same time.

Yes, and if that kind of yeast permeates the air, and dominates the existing population, every winemaker will be forced to deal with the ramifications.

Thomas, I can't pretend to have any expertise in this area, but I did find a fascinating article on this yeast at the Wine Research Centre at the University of British Columbia. The Fact Sheet is here.

The Fact Sheet discusses the charges of Dr. Joe Cummins, which I alluded to above.

I don't see that the Centre deals with you point, although I did not read all of the exhibits. I was struck by a couple of points, though.

Consumers will benefit directly since wines produced with ML01 will be free of allergenic bioamines and precursors to carcinogens produced by lactic acid bacteria.

It's been some time since I've read any concerns about precursors to carcinogens being present in wine; I wonder what the current scientific basis for the concern is.

Wineries will benefit from the use of ML01 since this yeast efficiently conducts the MLF, no spoilage of wine will occur due to stuck MLF, wines have lower volatile acidity (acetic acid – experts opposed to ML01 have predicted an increase in volatile acidity without any data available to them), colour properties of wine are improved, wine quality is higher, wines are more fruity and have an improved mouthfeel (body).

I had thought this was a yeast for jug wines and so called Fighting Varietals, but this sounds like the yeast might be useful for fine wines as well.

Regards, Bob

PS: On our previous email correspondence, "Is not the gleaning of the grapes of Ephraim better than the vintage of Abiezer?" Judges 8:2. B.

Thomas, I can't pretend to have any expertise in this area, but I did find a fascinating article on this yeast at the Wine Research Centre at the University of British Columbia. The Fact Sheet is here.

The Fact Sheet discusses the charges of Dr. Joe Cummins, which I alluded to above.

I don't see that the Centre deals with you point, although I did not read all of the exhibits. I was struck by a couple of points, though.

Consumers will benefit directly since wines produced with ML01 will be free of allergenic bioamines and precursors to carcinogens produced by lactic acid bacteria.

It's been some time since I've read any concerns about precursors to carcinogens being present in wine; I wonder what the current scientific basis for the concern is.

Wineries will benefit from the use of ML01 since this yeast efficiently conducts the MLF, no spoilage of wine will occur due to stuck MLF, wines have lower volatile acidity (acetic acid – experts opposed to ML01 have predicted an increase in volatile acidity without any data available to them), colour properties of wine are improved, wine quality is higher, wines are more fruity and have an improved mouthfeel (body).

I had thought this was a yeast for jug wines and so called Fighting Varietals, but this sounds like the yeast might be useful for fine wines as well.

Regards, Bob

PS: On our previous email correspondence, "Is not the gleaning of the grapes of Ephraim better than the vintage of Abiezer?" Judges 8:2. B.

Apparently, Bob, the promoters of this new yeast have taken the concern that I bring up into consideration. This is a quote from that fact sheet you linked.

"We have indeed considered that the ML01 yeast, same as other wine yeasts and the parental strain S92, might become resident in a winery. It is for this very reason that we tested what number of ML01 yeast cells is required to conduct the malolactic fermentation. From Figure 5 (Husnik et al., 2007) it is clear that no malolactic fermentation occurred when less than 1% of ML01 yeast was present in the inoculum at the start of fermentation. Even without washing and cleaning the fermentation tanks in which ML01 was previously used, it will be impossible to reach a population of 106 cells/ml of ML01 under the worst circumstances. Apart from the malolactic fermentation which is conducted by ML01 only when high cell numbers are present, ML01 is identical to the parental strain S92 and resident ML01 cells in a winery is therefore of no concern."

Whether or not they answer the concern sufficiently, I am ill-equipped to render an opinion. But it's obvious that others have raised the issue or they would not have been defending the yeast.

Re, the quote you provide from Judges: does a Biblical reference qualify as a documented fact?

Thanks, Thomas, I went past that discussion in the UBC materials.

The Biblical issue you raise is much too weighty for me to address -- one thing is certain, Ephraim was an actual place with lots of hills and fertile valleys, and the Bible has a number of references to the drunkards of Ephraim. But your question can lead to discussion of religion and other confusing things. Treat my comment as a possible lead on your search.

GMO yeasts seems much less controversial!

Thomas,
Even if MLO1 dominates a vineyard or winery, isn’t it possible to sulfite the must at crush to subdue the activity of this yeast and inoculate with a healthy (large cell count) starter culture of a “desired strain” of yeast so that the ‘desired strain” and not the MLO1 will dominate alcoholic fermentation.

Salute

Victor, yeasts to improve flavor and aroma may be in the pipeline but at the moment I believe only one GMO yeast, ML01, will be released this year. The purpose of ML01 is to make alcoholic and malolactic fermentations, normally a two-step process, occur at the same time.

Yes, and if that kind of yeast permeates the air, and dominates the existing population, every winemaker will be forced to deal with the ramifications.

So I'm intrigued by this argument, Thomas. We've had Frankenyeasts around for some time now that have been specifically engineered (albeit the old-fashioned way) to out-compete the natives. I can certainly see how they'd come to permeate the atmosphere of a given winery to some extent, but is there any evidence that they've been spreading beyond those environs to contaminate other areas?

Victor, yeasts to improve flavor and aroma may be in the pipeline but at the moment I believe only one GMO yeast, ML01, will be released this year. The purpose of ML01 is to make alcoholic and malolactic fermentations, normally a two-step process, occur at the same time.

Yes, and if that kind of yeast permeates the air, and dominates the existing population, every winemaker will be forced to deal with the ramifications.

So I'm intrigued by this argument, Thomas. We've had Frankenyeasts around for some time now that have been specifically engineered (albeit the old-fashioned way) to out-compete the natives. I can certainly see how they'd come to permeate the atmosphere of a given winery to some extent, but is there any evidence that they've been spreading beyond those environs to contaminate other areas?

Mike and Victor, too,

Many winemakers in California (and this is a recent conversation that took place online) will admit that, while they can start their fermentations with a selected yeast, they really cannot tell for sure which of the populations in the environment can or will become dominant and take over the fermentation.

Different yeasts have different capacities--some have higher resistance to SO2, some lower; some can ferment to higher alcohols, some lower; some can scavenge an existing fermentation population and wipe it out, some cannot; and on and on.

Even the cleanest winery can introduce yeast unknowingly, on someone's shoes for instance, tires that back up into the loading area, and other possibilities. In fact, Mike, some of the winemakers also admit that because of the already engineered yeasts, it's likely that so-called native yeasts aren't much in use anymore because they may have been infiltrated and are no longer natives.

Cultivated yeasts are intended to reduce risk as well as offer specific benefits, but they have their idiosyncratic ways and they can introduce something else into the equation.

I think that since the fact sheet on the MLO1 addresses the population contamination issue, there must be the potential for risk, even though they dismiss that possibility. If they have a vested interest, independent studies to back up their claims are necessary.

It is very possible that on a cluster of grapes (I’ll even say on a single berry) there could be blooms of various species of yeast (bacteria also) and strains of yeast (bacteria also) just waiting for the skin to be broken and its juice extracted. (And of course their environment would have to be favorable for them to do the things they do). Certain naturally selected wine yeast strains are said to have “killer instinct”. What does this actually mean? Do they “kill” other species or strains of yeast and bacteria? Or is it because of their ability to assimilate quickly (fast start ups); tolerate high levels of sulfite; tolerate wide temperature ranges; low nutrient requirements that gives them the edge in dominating alcoholic fermentation? Does anyone really know how “social” these little creatures are? Are they only concerned with there small segment of a drop of juice? The strain which dominates in population will dominate alcoholic fermentation.

Salute

Thanks Thomas.

Salute

It is very possible that on a cluster of grapes (I’ll even say on a single berry) there could be blooms of various species of yeast (bacteria also) and strains of yeast (bacteria also) just waiting for the skin to be broken and its juice extracted. (And of course their environment would have to be favorable for them to do the things they do). Certain naturally selected wine yeast strains are said to have “killer instinct”. What does this actually mean? Do they “kill” other species or strains of yeast and bacteria? Or is it because of their ability to assimilate quickly (fast start ups); tolerate high levels of sulfite; tolerate wide temperature ranges; low nutrient requirements that gives them the edge in dominating alcoholic fermentation? Does anyone really know how “social” these little creatures are? Are they only concerned with there small segment of a drop of juice? The strain which dominates in population will dominate alcoholic fermentation.

Salute

Generally, the so-called killer yeasts are quicker to multiply and so they overwhelm the so-called native population.

Some people claim that sacc. c. yeast cells do not live on grape skins, but are in the environment.

Thanks again Thomas.

Salute

Even the cleanest winery can introduce yeast unknowingly, on someone's shoes for instance, tires that back up into the loading area, and other possibilities. In fact, Mike, some of the winemakers also admit that because of the already engineered yeasts, it's likely that so-called native yeasts aren't much in use anymore because they may have been infiltrated and are no longer natives.

This is exactly what I was wondering about. It would seem to me, then, that the genie is somewhat out of the bottle with this? If this is the issue, then isn't the particular technique used to achieve genetic modification less important than the fact that we're introducing modified organisms into the environment?

I think that since the fact sheet on the MLO1 addresses the population contamination issue, there must be the potential for risk, even though they dismiss that possibility. If they have a vested interest, independent studies to back up their claims are necessary.

I agree that independent studies would help to clear the issue up and that they probably should be done. But it seems to me that this would affect many more of the available yeast products than just the ML01.

Even the cleanest winery can introduce yeast unknowingly, on someone's shoes for instance, tires that back up into the loading area, and other possibilities. In fact, Mike, some of the winemakers also admit that because of the already engineered yeasts, it's likely that so-called native yeasts aren't much in use anymore because they may have been infiltrated and are no longer natives.

This is exactly what I was wondering about. It would seem to me, then, that the genie is somewhat out of the bottle with this? If this is the issue, then isn't the particular technique used to achieve genetic modification less important than the fact that we're introducing modified organisms into the environment?

I think that since the fact sheet on the MLO1 addresses the population contamination issue, there must be the potential for risk, even though they dismiss that possibility. If they have a vested interest, independent studies to back up their claims are necessary.

I agree that independent studies would help to clear the issue up and that they probably should be done. But it seems to me that this would affect many more of the available yeast products than just the ML01.

You bet, on both counts.

you almost never remotely say anything in debates - you write in a world of implications to keep safe from ever having really said anything.

Here's one: That is a frickin' lie.

Bravo.

[David M. Bueker]

you almost never remotely say anything in debates - you write in a world of implications to keep safe from ever having really said anything.

Here's one: That is a frickin' lie.

Bravo.

There's an insightful comment.

you almost never remotely say anything in debates - you write in a world of implications to keep safe from ever having really said anything.

Here's one: That is a frickin' lie.

Bravo.

There's an insightful comment.

Ok, ok, David. We have moved on in this subject. Care to contribute?

[David M. Bueker]

you almost never remotely say anything in debates - you write in a world of implications to keep safe from ever having really said anything.

Here's one: That is a frickin' lie.

Bravo.

There's an insightful comment.

Ok, ok, David. We have moved on in this subject. Care to contribute?

I was preapred to leave it alone - thank Oliver for bringing it back up.

As for the topic - the issue to me is that almost nothing can ever be proven. You cannot prove that a GM strain of yeast will never out muscle the local strains, and you cannot prove that a winemaker can fully protect the wines from it. This is part of what is so frustrating about the whole GM argument. It's not unlike the screwcap debate in that however long a trial lasts I doubt it will ever be long enough to convince the sceptics.

you almost never remotely say anything in debates - you write in a world of implications to keep safe from ever having really said anything.

Here's one: That is a frickin' lie.

Bravo.

There's an insightful comment.

Ok, ok, David. We have moved on in this subject. Care to contribute?

I was preapred to leave it alone - thank Oliver for bringing it back up.

As for the topic - the issue to me is that almost nothing can ever be proven. You cannot prove that a GM strain of yeast will never out muscle the local strains, and you cannot prove that a winemaker can fully protect the wines from it. This is part of what is so frustrating about the whole GM argument. It's not unlike the screwcap debate in that however long a trial lasts I doubt it will ever be long enough to convince the sceptics.

In the case of out-muscling local strains, that seems to have been proved by the present cultivated yeasts. A lot of people in California claim that those who say they ferment only with local yeast can't prove it, mainly because, in the end, it's hardly ever, if at all, when local yeast finishes a fermentation. The real question then is, do they even start them.

Were I producing wine, my concern would be whether an engineered yeast becomes THE yeast or just another cultivated yeast competing for the sugar. I believe that kind of question can be proved in lab experiments.