Connect with us

Hi, what are you looking for?



Making Better Biofuels, from Beer Broth

Cornell researcher make fuel products from beer brothCornell researchers have figured out a way to make biofuel products from beer broth,  and their findings are so exciting that the normally unflappable Royal Society of Chemistry has conferred “hot” status on a paper describing the beer-to-biofuel process. The beer broth in question isn’t suitable for tippling, which makes it a little less exciting to some of us, but it could lead to a low-cost method for producing high-value biofuel precursors.

A Beer Broth Primer

Like beer, ethanol is produced by microbial digestion in the form of yeast fermentation. In the two-step process, starches like cornstarch are converted to sugar by enzymes, and then the sugar is converted to ethanol by yeast.

According to writer Anne Ju of Cornell, the fermentation broth for ethanol is identical to that of beer in terms of its chemistry, which is why the ethanol industry calls it “beer broth,” except that for a variety of reasons you would not want to drink it.

Ethanol is water-soluble, so the next step to producing fuel is to separate ethanol from the water in the beer broth. This distillation process is energy-intensive, and it is a main reason why the cost of ethanol fuel relatively high.

A Step Toward Low Cost Biofuel

The Cornell team approached the problem from the perspective of creating an oily, non-soluble fuel precursor in beer broth that could be separated from water without undergoing expensive distillation.

Using donated beer broth from a nearby corn ethanol plant, they tailored the community of microbes in the broth to draw the fermentation process out to a series of steps.

The end result was a fuel precursor called caproic acid, a fatty acid that occurs naturally in some animal fats.(Another name for caproic acid is hexanoic acid, referring to its derivation from hexane, which is a constituent of gasoline).

The tricky part was to get the pH and temperature into the right range, to prevent the microbes from shifting over to methane production.

What Now, Beer Broth?

According to Ju, the process can be integrated easily into existing ethanol production facilities. However, researchers used 5-liter tanks for bioreactors, which is quite a bit smaller than the massive commercial scale tanks used in the ethanol industry. Scaling up will be the next hurdle.

Now that the concept of tailoring beer broth communities has been proven, the team also expects to be able to create communities of microbes that produce other products, too.

A Bioeconomy Role for Beer

While we’re on the subject of beer, it’s worth nothing that drinkable beer has been starting to play a role of its own in the emerging bioeconomy, which President Obama recently expressed as the National Bioeconomy Blueprint for transitioning the U.S. out of fossil fuels and petrochemicals.

Noted microbrewery Karl Strauss got a jump on things a few years ago, when it started up a venture to convert its waste yeast to ethanol.

At the mega-brewery end of the scale, AB-InBev (formerly Anheuser Busch) recently partnered with Blue Marble Bio to convert brewery waste into carboxylic acids (fatty acids used in soap making, among other things) as well as biogas.

Image: Some rights reserved by Greencolander.

Follow me on Twitter: @TinaMCasey.

Don't want to miss a cleantech story? Sign up for daily news updates from CleanTechnica on email. Or follow us on Google News!

Have a tip for CleanTechnica, want to advertise, or want to suggest a guest for our CleanTech Talk podcast? Contact us here.
Written By

Tina specializes in military and corporate sustainability, advanced technology, emerging materials, biofuels, and water and wastewater issues. Views expressed are her own. Follow her on Twitter @TinaMCasey and Google+.


You May Also Like

Clean Transport

The Biden administration under a new federal program is awarding grants to school districts all over the country. The grants will reach over 400...


Can electric vehicles benefit from the US Renewable Fuel Standard (RFS) scheme? Reuters reports that it is highly likely that they can. It appears...

Clean Transport

The Renewable Energy Standard that mandates the use of ethanol in fuels is up for review this year. Should it be abolished?

Clean Transport

Wireless charging roads equipped with energy storage systems are promising electric vehicle solutions by virtue of their strong advantages in time saving and reduced...

Copyright © 2023 CleanTechnica. The content produced by this site is for entertainment purposes only. Opinions and comments published on this site may not be sanctioned by and do not necessarily represent the views of CleanTechnica, its owners, sponsors, affiliates, or subsidiaries.