Made In the San Francisco Bay Area
GigaYeast, Inc.

About Us

Jim Withee (Founder, CEO, Chief Scientist, Head Janitor)

jimandroxieThe most mysterious and beautiful part of brewing is fermentation.  Think about it:  a live microorganism transforms the sugars and protein from malt into a complex flavorful fizzy beverage.  You’d think by now someone would have figured out how to make synthetic beer.  But they haven’t.  We still depend on live brewers yeast for that transformation today just like humans have for thousands of years.  It’s one of the most complex and beautiful transformations in nature and the alchemy of fermentation has fascinated the best scientific minds for hundreds of years. I founded GigaYeast, Inc. to be a part of the craft beer and home brew movement using the skills and love for yeast and fermentation I cultivated over 20 + years of science and beer.  As a young graduate student I received a PhD for studies on yeast genetics.  After graduate school I worked at the Saccharomyces Genome Database–  that’s where the then newly sequenced DNA of brewers yeast was first completed.  All the while I was watching the craft beer movement grow and gaining a deeper and deeper appreciation for truly fine brew.  After years of work as a Government Scientist I finally quit my high paying job and built the GigaYeast Laboratory.  I put everything I know (and own!) into this laboratory and the end result is a process that creates perfect yeast.  Now get out there and brew–  we’re getting thirsty making all this beautiful yeast.




Steve Smith (Head of Sales/Marketing and Yeast Science Guy)

steve Dr. Steve Smith received a PhD in Microbiology from North Carolina State University in 1995 for his research on lipid-mediated gene regulation and cellular respiration in the yeast Saccharomyces cerevisiae. Steve then moved to San Francisco for a postdoctoral fellowship at the Gladstone Institute where his research focused on diabetes, obesity and cardiovascular disease, followed by research positions in several Bay Area biotech companies. He began home brewing in 1990 and has remained an active brewer for >20 years, with favorite styles to brew being California Common and about anything Belgian.




Loren Gibbs (Head of Production) 

DSCF6603 I worked in food service and restaurant management for most of my life before coming to GigaYeast.  Food and beer together are a natural pair and I enjoy learning about and consuming both. I have a degree in history from California State University Sacramento. Drinking beer taught me to appreciate the taste of great beer from different places around the world and from different eras.  History taught me how beer has influenced, and been influenced by, human cultures across the world and through the ages.  I’ve never lost a match of Edward Forty Hands.  If you don’t know what that is you’ll have to stop by GigaYeast and ask me.





Cassie TenCate (Yeast Laboratory Technician)

IMG_20160308_162551As a native South Dakotan, I grew up around cows and corn. My family introduced me to craft beer early in life, and I was hooked. While attending South Dakota State University I started working at the local brewing company. There my love for craft beer really blossomed. I started South Dakota’s first Girls Pint Out chapter, a women’s craft beer organization. After I graduated in May of 2015 with a degree in Biological Science, I married my wonderful husband Dustin and moved to the Bay Area. Now that I work at GigaYeast; I get to combine my two favorite things, beer and science. In my spare time I also run the San Jose Girls Pint Out chapter.





Amelia McCullough (Office Manager)

Amelia McCulloughI joined GigaYeast as the Office Manager in August 2016. Outside of the office, I enjoy homebrewing and cheering for the Wisconsin Badgers. New to the Bay Area, I have been exploring the craft beer scene along with my trusty sidekicks Ben and Flint. In my former life, I was Co-Director for an archaeological laboratory in Belize, researching Maya sites. I highly recommend Belize as a great vacation destination for both beach lovers and trail blazers.







Roxey (The Dog)

Roxy Roxey splits her time in the office between lying in the sunny patch near the window, scaring off delivery persons and getting petted by brewers.