The first phase of our project was to grow lactic acid bacteria and yeast together. We knew that a multi-organism system could have a variety of possible advantages in synthetic biology. We wondered if there were any possible applications for this system in the brewing industry. This brought on a set of questions that we tried to answer over the summer:
Would brewers be comfortable brewing with this co-culture of LAB and yeast?
How do you get approval, nationally and internationally, for a genetically modified organism?
Is it possible to release a genetically modified organism into the wild?
Are each of these applications feasible and important?
We talked to brewers about their experience brewing with multiple species of yeast and if they would sell it. A brewer, Matt Riggs, stated that consumers will be wary of GM product, so he wouldn't sell that right now, but he personally would try it. He suggested targeting industrial applications in the short-term and the brewing field in the future. Taking his comments and suggestions we geared our project/co-culture toward industrial applications, like using our system to create valuable products such as lactic acid.
Q1: Do you have any experience brewing with multiple species of yeast or non-yeast organisms?
A1: When I was studying brewing in Germany, we sometimes used to use lactobacillus to make sour beers, but this was not a direct co-culture like what you are doing in your lab. We would create a separate culture of lactobacillus and add it to the fermenter in the last 15 minutes of the fermentation, immediately followed by pasterization. The amount of alcohol in the fermentation culture at that point was too high for the lactobacillus to survive, but the lactic acid they already produced was sufficient to give the beer the sour flavour we were looking for.
Q2: What is your opinion on brewing with GMO's?
A2: I should be careful about how I say this. I have heard of people doing some interesting things with GM brews, but I would never mess with that. I would lose most of my business. The fact of the matter is, people don't trust GM products to that extent. If I tried to sell that, I would lose almost all of my business. I think the technology you are working with could do a lot of good in industrial applications like cellulosic ethanol; but I don't think it is viable for something people directly consume.
Q3: Do you think there will ever be a market for specialty brewing with GM organisms?
A3: No, I don't.
While it was fascinating to talk with Mr. Riggs about his many years of experience in brewing, we ultimately decided to move our project focus away from brewing applications after this interview.
We also attended the CABBI (Center for Advanced Bioenergy and Bioproduct Innovation) annual retreat, where we spoke with researchers dedicated to converting biomass into usable products. They gave us suggestions on how to improve the industrial viability of our system, such as testing its behavior under anaerobic conditions rather than aerobic. Most industrial-scale bioreactors function under anaerobic conditions in order to limit the amount of carbon leaving the system as carbon dioxide. This maximizes the amount of carbon that can be converted into the desired product.
Many of the researchers at this retreat agreed that a multi-organism system like the one we were working with could have profound advantages in the context of bioprocessing. After having the opportunity to speak with these experts, it was clear to us that we wanted to take our project in an industrially-oriented direction.
Pictures from when we presented our work at the CABBI annual retreat where we had active dialogue with professionals in the research community. We discussed about iGEM requirements, RFC 10 standard, and even synthetic biology as a whole. The research professionals who stopped by our poster gave us advice on how to improve our project to get better results.