Low water activity foods (LWAFs) — products with a water activity (aw) below 0.85 — have historically been considered low-risk for microbiological hazards because their limited “free” (unbound) water in the formulation prevents bacterial growth. However, foodborne illness outbreaks — most notably the 2008–2009 salmonellosis outbreak linked to peanut butter — revealed that pathogens can survive for extended periods in LWAFs, even in the absence of growth.  

With the implementation of the Food Safety Modernization Act, food processors are now required to validate control measures to reduce microbial risks in LWAFs. Thermal processes like roasting, drying, extruding, and baking that are typically used for functionality or preservation are now often relied upon as microbial “kill steps.” If these processing steps are used as microbial kill steps, processors must scientifically validate that these methods effectively reduce pathogens.  

In this webinar, we will detail the principles, design, and execution of validation strategies for mitigating microbiological hazards in LWAF. 

Meet the Presenters

With over 15 years of expertise in food safety research, Shirin serves as Technical Director in the Eurofins Advanced Food Microbiology Group. She provides food safety consultation to food companies and equipment manufacturers, to assist with developing strategies to comply with food safety regulatory and FSMA requirements. Shirin's educational background is in chemistry, with a Bachelor of Science degree from Tehran University, followed by the second bachelor’s degree in food science and a master’s degree in food microbiology, both from the University of California, Davis.

Shirin's leadership includes overseeing complex food safety projects and evaluating a range of conventional thermal processes with a focus on low water activity foods, novel technologies, and chemical treatments as pathogen control measures. Shirin has co-authored two book chapters and contributed to numerous peer-reviewed publications in food safety and microbiology journals. 

Martha Kimber serves as a Senior Technical Manager in the Advanced Food Microbiology team at the Eurofins Micro Lab in Fresno, CA. This team was formerly known as the Food Safety group at The National Food Lab. She has been part of this team for over 14 years and specializes in providing clients with process authority support and customized challenge studies for a variety of food products, based upon their regulatory requirements and research objectives.

Prior to Eurofins, Martha worked at Hain Celestial, the California Department of Public Health Food and Drug Lab, and Hall Wines. Martha holds a BS in Microbiology from UC Davis, and an MS in Food Science from UC Davis. 

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