![Science on the SPOT HD Video Podcast show](https://d3dthqtvwic6y7.cloudfront.net/podcast-covers/000/039/400/small/science-on-the-spot-hd-video-podcast.jpg)
Summary: Whether it’s a lager or ale, sour or bitter, dark or light, most beer has one thing in common: yeast. KQED Science visits a commercial yeast laboratory and a local brewery to reveal how this key ingredient is a major player in both science history and beer production.