Since you asked....

Recently I recieved an e-mail from a good friend of mine asking about my opinion on the use of genetically engineered yest in the practice of wine making. Apparently this is a big issue in the South African wine industry right now.

Genetic engineering and wine happen to be two of my most favorite topics so I couldn't resist writing back with my thoughts about the subject. I actually enjoyed thinking about it so much I thought I would share.

Her question...

Sitting in my intro to biotech class right now and we’re discussing a case that deals with using GM yeast in the production of grapes at wineries in S.Africa. Any thoughts coming from the science side and someone who knows something about the wine making process?

My answer:

Ok so you asked about wine and yeast..two of my favorite topics! Unfortunately I haven't been following the whole GMO
controversy as closely as I once did, so I am not current on the "view" of the scientific community on the topic. As far as I know the community is still very divided on the subject. Until long term studies are done on the safety and effect of widespread distribution of GMO organisms the field will be very divided. I do know that many of the big pharma companies that were once investing heavily in R&D of GMO crops (corn, soy, cotton, etc.) have slowly moved away from agressive growth and funding to spinning off their plant biotech divisions as independent companies which have slowly faded due to public pressure and negative press. However most of those companies as I said were focusing on crops that are able to resist herbicides or produce their own "pesticides". These are scary to consumers because they feel there are unexplored health risks or the potential for non-GMO plants to inherit the modifications of the GMO crops and thus have the very plants we want to eliminate with herbicides become resistant as well.

The yeast argument on the other hand seems to fall more in the category of stem cell research wherein there is minimal risk to cross contamination because the yeast would be used in the confines of a winery and not out in the field where it could run the same contamination risks as I mentioned above (more so actually because the ability of yeast to cross breed would be far greater than plants). But rather it becomes a question of should we be manipulating a natural process at all. In fact we have been
manipulating nature for years with selective breeding and selection of desirable characters. This is certainly true of the wine industry. Wine can be made naturally by picking grapes and allowing them to naturally ferment...that's how wine was discovered. But you wouldn't necessarily want to drink it, or sell it. So wineries will add yeast cultures to their fermenting grapes in order to both
speed up the process (more yeast = more fermentation) and to control the quality (good yeast = good wine). So this natural process isn't really all that natural anymore. Many wine connoisseurs will tell you that they can taste a wine and tell you where it came from sometimes down to the actual vineyard by the specific qualities of the wine. When you make wine you don't wash the grapes first. Everything goes in dirt, spiders and all (isn't that a nice thought), which will ultimately affect the flavor of the wine. So given that the kinds of bacteria, dirt whatever that is particular to a certain vineyard will give wine a unique flavor. Using biologically engineered yeast and bacteria could mask these nuances or allow vintners to manipulate the flavor of the wine according to the strain they use. So the question becomes what really is the difference if the common practice is to add yeast anyway.

Another use I read for GMO yeast and bacteria would be to help avoid the use of sulfites in the wine making process. As I said everything goes in the mix, and so to keep unwanted critters from growing and contaminating your wine winemakers add sulfites. A yucky terrible chemical,and something that many people are allergic too. There are many people who can't drink red wine because of the added sulfites. More sulfites are used in red wine I think because the skins are around during the fermentation process whereas they are not in white. In my book avoiding the use of sulfites would be a wonderful thing.

Here are the issues as I see it.

1. Cost and availability. R&D to make a genetically engineered yeast or bacteria is expensive. Would wineries who use this technology charge more for this wine and would that be desirable? Would you pay the same for a bottle of 2 year old wine that had the same properties as a reserve blend that has been aged for 5-10 years? In this age of digital cameras and instant messaging we have become accustomed to instant gratification, so there could be a market for that kind of product.

2. Safety. There is no doubt that the public in general is wary of GMO products in the food supply. This fear shut down aggressive plant biotech expansion as
I mentioned. However yeast is filtered out of the wine before it is bottled, some will remain but to a very low degree and the kind of changes they are talking
about making to these yeast are not the kind of changes they make to crop products (ie. no internal pesticides or herbicide resistance) they basically just alter the metabolic processes already naturally occurring in yeast. So the fear factor might not be as big of an issue for consumers, although you can't escape those who would only drink organic wine or eat organic food and think the term GMO = evil. But as I said sulfites are evil too and so I think that seeing the big picture
might help people understand some of the benefits.

3. Old practices vs. new practices. Wine is one of those industries that I think would benefit from resisting too much modernization. In my opinion many mass produced wines are good, very drinkable as a table wine. But the best wines I have ever had are made in small(er) batches and aged well. I don't think this can ever be replaced. Another danger would arise if using GMOs in winemaking (or any practice) becomes the norm smaller producers may have to comply in order to be competitive which could end up being too costly.

As I was doing some research on the subject I came across this article that also reflects my opinions on the subject.

What are your thoughts?