Over the past decade, polymerase chain reaction (PCR) has become a trusted tool for breweries large and small who wish to screen their products for contamination before packaging and distribution. Many breweries have purchased PCR platforms to get quick yes or no answers to the presence of diastatic yeast, hop resistant bacteria, or foreign yeast species such as Brettanomyces. However, not all PCR platforms are created equal, and even with high-end instruments where quantitative analysis is possible, there is a potential for the presence of contaminants whose genes are not targeted.

In this seminar, John Giarratano and Nicole Balistreri dive into the potential pitfalls of trusting PCR alone. Additionally, they discuss examples of contaminant organisms that are not tagged by traditional PCR primers, as well as inexpensive alternatives such as plating that can be used alongside PCR to increase detection.

Learning Objectives

• Recognize the limitations of using PCR only in a quality assurance and quality control (QA/QC) program
• Learn the difference between PCR platforms such as endpoint and qPCR
• Explore how to use inexpensive techniques such as plating to screen for contaminants in a brewery
• Discuss ways to integrate PCR and plating to improve a QA/QC program
• Know how to identify brewery spoilers and when to dump a batch of beer

About the Speakers

Nicole Balistreri, Yeast Plant Manager

Prost Brewing Company

Nicole Balistreri grew up at a family-owned and operated winery in North Denver and has been around fermentation since a young age. Her academic endeavors were focused on biological sciences and biochemistry at Colorado State University. Nicole entered the brewing community through Blue Moon RiNo around seven years ago. Since then, she considers it a privilege to have worked in the Coors Corporate Sensory department, the Coors Quality Micro Lab, and the Inland Island quality lab where she has been the quality manager until recently. Nicole has just transitioned into a new role, joining the team at Prost Brewing Company as the yeast plant manager. She feels that the best way to gain a well-rounded understanding of a subject is through tribal knowledge and collaborating with peers.

John Giarratano, CEO

Inland Island Yeast Labs

John Giarratano founded Inland Island back in 2014 and continues to lead the company in customer service, quality, and innovation. John's previous career in pharmaceutical Good Manufacturing Practice (GMP) and bio fuels introduced him to the world of yeast propagation, and he saw the need for a local yeast lab in Colorado. What started as selling vials of yeast to homebrewing shops quickly blossomed into an industry-leading yeast laboratory supplying breweries large and small from coast to coast and beyond. Many breweries are too small to have their own labs, so John's team provides them with the quality control and care that they would not have access to otherwise. John's proud of the niche he and his team have carved in the industry and believes that yeast is the single most important ingredient in beer. In his spare time John volunteers with the Master Brewers Association of the Americas and strives to educate the brewing community and public alike on yeast management and brewing practices. John also enjoys snowboarding, gardening, and spending time with his wife and two daughters.