Most people don’t think twice about pouring kibble into a pet’s bowl or tearing open a packet of crackers. Dry foods feel safe. They sit on shelves for months without spoiling, don’t require refrigeration, and look and smell unchanged long after initial purchase.

But “dry” does not mean risk-free. Pathogens such as Salmonella and Listeria monocytogenes can survive in low-moisture environments for months or even years, and when contamination happens, the effects can be widespread. Whether the end consumer is a child snacking on peanut butter crackers or a dog chewing jerky treats, the hazards—and many of the prevention strategies—overlap far more than most realize. Understanding these connections can strengthen food safety across sectors, protecting both people and pets.

The connection between pets and humans is well documented, with many pets now viewed as part of the family. As a result, pet food is no longer an afterthought but is considered just as important as the food of human members of the household. With know-how on working with brick and mortar retailers, on-line shopping platforms and opportunities for increased positive brand positioning, it is not surprising the number of acquisitions of pet food companies by human food companies in recent years. Additional parallels from a processing and manufacturing perspective also reinforce the business case for the expansion of human food companies into pet food. Of note (and certainly not an exhaustive list), General Mills purchased Blue Buffalo in 2018, and Post Holdings entered the pet food market by acquiring several brands from J.M. Smucker in 2023. Additionally, Mars and Nestlé have sold both human food and pet food for decades.

Shared Risk: Low-Moisture Foods

Pet diets often include dry kibble, jerky treats, and freeze-dried or dehydrated proteins which are considered low-moisture foods (LMFs). LMFs are defined as those with a water activity below 0.85. While this level of available water prevents microbial growth, it does not eliminate pathogens once present. Instead, microorganisms can persist in a dormant state, becoming more resistant to heat and other stressors.

The most concerning hazards in LMFs are Salmonella, Cronobacter and Escherichia coli. (while less common Listeria monocytogenes is still a risk.) These hazards emphasize the risks associated with seemingly benign dry foods. Numerous outbreaks have been tied to LMFs in humans including Salmonella contamination in peanut butter, E. coli and Salmonella contamination in flour and Salmonella and Cronobacter concerns in dried spices and powdered milk respectively.

Despite their dry appearance, pet food products can provide a long-term refuge for pathogens. With both human and animal foods, contamination can occur at multiple stages: at the raw ingredient procurement steps, within processing environments, and after packaging during storage, distribution, or even in the household through improper handling. The microbial risks are not confined to one step but are woven into the very nature of LMFs themselves.

Regardless of whether discussing human food or pet food, pathogen contamination events can result from a variety of circumstances, such as the introduction of a pathogen:

• Through a contaminated ingredient (e.g., at the beginning of the line or at an intermediate step when an ingredient is added)
• Along the processing line where the product or its ingredients are exposed to the environment
• Introduction of an environmental pathogen by personnel in the plant
• Onto dry processing equipment through introduction of water (e.g., through condensation or a leaking roof).

The above list is a modification of FDA draft guidance for “Establishing Sanitation Programs for Low-Moisture Ready-to-Eat Human Foods…”– but it clearly applies to pet food (Link to source https://www.fda.gov/regulatory-information/search-fda-guidance-documents/draft-guidance-industry-establishing-sanitation-programs-low-moisture-ready-eat-human-foods-and).

In pet food, these contamination risks are not hypothetical.. In 2012, Salmonella contamination in dry dog food was linked to human illnesses in multiple states. More recently in 2021, several brands of pet food were recalled after more than 130 pet deaths and 220 illnesses were reported. And in August 2025, there was another recall of dog and cat food due to Salmonella and L. monocytogenes contamination. (https://www.fda.gov/safety/recalls-market-withdrawals-safety-alerts/viva-raw-issues-voluntary-recall-two-lots-dog-cat-foods-due-salmonella-and-listeria-monocytogenes)

The risks extend beyond the pet’s health. A dog fed contaminated kibble may appear healthy yet shed Salmonella in its feces. Humans can then be exposed by touching pet food, handling bowls, or cleaning up after the pet. Children, the elderly, and immunocompromised individuals are particularly at risk. Pet food contamination is not just a veterinary issue. It is a household food safety issue.

Overlap in Preventative Strategies

While human food and pet food are marketed and regulated differently, the science of prevention is strikingly similar. The Food Safety Modernization Act (FSMA) requires risk-based preventive controls for both human and animal foods. This alignment reflects an important reality: hazards in dry foods are not consumer-specific—they are science-specific. Whether the end user is a toddler eating cereal or a dog chewing on kibble, the microbial risks and the tools to mitigate them are shared.

Preventative strategies originally developed for human LMFs often have direct application in pet food. These include environmental monitoring programs to detect pathogens, dry sanitation practices to reduce the introduction of water which can inadvertently create microbial harborage sites, and kill-step validation to ensure that processes achieve the necessary lethality against resistant pathogens in low-moisture conditions.

Lessons learned in one sector often migrate to the other. Extrusion validation in pet food manufacturing now closely mirrors approaches in human snack and cereal production where thermal processing under low-moisture conditions must be validated for microbial control. Zone-based environmental monitoring is a long used best practice in human food facilities, and is increasingly standard in pet food plants to reduce cross-contamination between raw and finished product zones. Air handling strategies pioneered in dry dairy product facilities are also being adopted by pet treat producers, particularly those making freeze-dried or dehydrated products.

These parallels are not accidental. They reflect the simple fact that pathogens do not distinguish between crackers and kibble, peanut butter and pet treats. What matters is the environment in which the food is made and the rigor of the controls applied. The convergence of regulatory expectations, scientific insights, and industry practices highlights an important opportunity: when we strengthen safety systems for one type of dry food, we raise the standard for all.

A Connected Responsibility and Shared Interests

The overlap between microbial food safety in human low-moisture foods and pet food is more than a coincidence—it’s a call for shared learning and investment. To reduce risk, manufacturers of both commodities must:

• Recognize the shared science that underpins safety
• Invest in preventative controls and environmental monitoring to keep all products safe for the end user- human or pet
• Continue innovating in science and technology, like dry sanitation or other mitigation techniques to prevent contamination.

Ultimately, food safety does not stop at the dinner plate. It extends to the pet bowl, treat jar and the surfaces where food for every member of the household is prepared and consumed.

The kitchen and the kibble bag are more connected than we think. By treating them as part of the same food safety continuum, we can better protect the health of both people and our pets.

Photo credit and copyright: Beth Biros

Editors Note: One of the authors, Caitlin Karolenko, PhD will be presenting at the 2025 Food Safety Consortium in the session titled: Dry Doesn’t Mean Safe: Pathogens in Low Moisture Foods. For more information go to FoodSafetyConsortium.org and click on Agenda.