Flour is a pantry staple found in almost every household, yet it is often overlooked when it comes to safe handling and consumption. So, as holiday baking ramps up, we explore the risk of raw flour.
Top Takeaways:
- Flour is a raw product that may retain harmful pathogens when uncooked.
- Cooking flour-based foods to an internal temperature of at least 165°F (74°C).
- Gluten-free and other non-wheat flours are not safer than wheat flour.
- To safely enjoy raw cookie dough, opt for commercially prepared options labeled as safe for raw consumption.
What is flour?
Flour is an ingredient made by grinding grains, roots, seeds, or beans into a powder. It is an ancient staple ingredient in many cuisines worldwide, used to create a wide range of foods, including baked goods, sauces, coatings, pasta, and more.
The most common flour in the United States is wheat flour, but there are numerous varieties, each with unique properties and uses.
What is a raw ingredient?
A raw food ingredient is a natural, unprocessed, or minimally processed food item used as a starting point in cooking. It retains its original form, such as fruits, vegetables, grains, or meats, before being transformed into a dish or beverage. They provide the foundational flavors, nutrients, and textures of a dish.
Raw ingredients can pose risks if contaminated with harmful pathogens like bacteria, viruses, or parasites, that can lead to foodborne illnesses.
Improper handling, storage, or preparation of raw foods increases the risk of contamination.
Is flour a raw food?
Yes, flour is a raw agricultural product. Unlike foods that undergo heat treatment, such as pasteurization, flour may retain microorganisms from the growing environment and can include E. coli and Salmonella.
The retained pathogens can contaminate flour during harvesting, processing, or storage.
How does flour get contaminated?
Raw ingredients can become contaminated in many ways, even when following proper protocols.
Contamination can occur:
- In Nature: Flour is made from grains like wheat, which can become contaminated in the field by natural environmental factors such as bacteria (e.g., Salmonella, E. coli) from soil, water, or animal waste.
- During Farming and Harvesting: Farming methods, including the use of contaminated irrigation water or improper handling of grains during harvesting, can introduce pathogens.
- In Processing: At the milling stage, cross-contamination from equipment, facilities, or handling practices can introduce contaminants like bacteria or fungi.
- During Distribution and Storage: Flour can become contaminated during transport or storage if exposed to pests, moisture, or contaminated packaging.
- In the Home: Once purchased, improper storage, handling, or use can introduce pathogens, especially if flour is not kept in a dry, sealed environment or is used with utensils contaminated by raw foods.
Why is raw flour a risk?
Raw flour is a unique risk largely due to the widespread misconception that its dry, powdered form makes it safe for consumption.
In reality, raw flour is a minimally processed agricultural product that undergoes no treatment to eliminate harmful pathogens. These microorganisms, such as E. coli or Salmonella, can contaminate wheat during harvesting, processing, or storage and remain viable in the flour.
While raw eggs are often perceived as the primary risk in cookie dough or batter, raw flour is an equally significant hazard that can cause serious foodborne illnesses.
Does baking destroy the pathogens in raw flour?
Baking flour-based foods at appropriate temperatures destroys harmful pathogens like E. coli and Salmonella. Most baked goods should be cooked to an internal temperature of at least 165°F (74°C) to ensure safety.
Always follow baking instructions carefully and avoid undercooking items like cookies, cakes, or breads.
Are gluten-free or other flours safer than wheat flour?
No, gluten-free and other flours are not inherently safer. All raw flours, regardless of their source (e.g., almond, rice, oat, etc.), have the potential to be contaminated with harmful pathogens and should be treated with the same precautions as wheat flour.
I want to eat raw cookie dough, can I do so safely?
Unless you purchase pre-made cookie dough specifically labeled as safe for raw consumption, there is no guaranteed safe way to eat raw dough.
Heat-treated flour, which manufacturers have processed to eliminate harmful pathogens, is not widely accessible to home cooks.
While some recipes suggest DIY methods to “heat-treat” flour at home, such as baking it in the oven or microwaving it, these methods are inconsistent and may not effectively eliminate all pathogens, including Salmonella, which is particularly heat-resistant in low-moisture foods like flour.
To safely enjoy raw cookie dough, it’s best to stick to commercially prepared options specifically designed for raw consumption.
What are the symptoms of a foodborne illness caused by raw flour?
Eating contaminated raw flour can cause the same symptoms as many foodborne illnesses, such as stomach cramps, diarrhea, vomiting, and fever.
If you suspect a foodborne illness, seek care from a medical provider.
The good news.
You can still enjoy your favorite baked goods safely. Simply ensure that they are cooked thoroughly to eliminate any harmful pathogens. Proper baking not only enhances flavor but also protects your health.
If you have any questions about ingredients or ideas for a blog post, please send us an email or submit your idea to us at go.msu.edu/cris-idea.
Learn more: citations and further readings.
Feng, Y., & Archila-Godínez, J. C. (2020). Consumer Knowledge and Behaviors Regarding Food Safety Risks Associated with Wheat Flour. Journal of Food Protection, 84(4), 628–638. https://doi.org/10.4315/jfp-19-562
U.S. Food and Drug Administration. (2024.). Handling flour safely: What you need to know. https://www.fda.gov/food/buy-store-serve-safe-food/handling-flour-safely-what-you-need-know
U.S. Food and Drug Administration. (2023). Flour: A raw food and other safety facts. https://www.fda.gov/consumers/consumer-updates/flour-raw-food-and-other-safety-facts
Verrill, L., Lando, A., Wu, F., Tatavarthy, A., & Obenhuber, D. (2021). Consumption of Raw Flour in the United States: Results from the 2019 U.S. Food and Drug Administration Food Safety and Nutrition Survey. Journal of Food Protection, 85(1), 31–35. https://doi.org/10.4315/jfp-21-256