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Flour is Raw Food

Flour is a raw product!

Consuming flour before it has been cooked can make you sick because it may contain bacteria.   E. coli is a common bacteria in the digestive tract of animals and humans. 

Some strains of E. coli can be harmful and can cause disease. Illnesses linked to consumption of flour have been investigated in both the United States and Canada, including here in BC.

Flour is made of dried wheat or other grain varieties grown in open fields.  When harvested the grains are separated from the wheat stalks (chaff) and the grains are sent from the fields to silos for storage and to flour mills for processing.  In the field, during the journey from the field to the flour mill, and in the mill, wheat may get contaminated by animal feces.  Animal feces are the most likely source of E. coli contamination in wheat. Feces may be introduced into flour through, for example, improperly composted animal manure used as fertilizer on the wheat; or from fecal-contaminated irrigation water or run-off water, or from birds, insects, deer or rodents that may be present in the open wheat fields, or in barns, silos or flour mills.  E. coli present in the dried, ground flour will not multiply but can survive, even in the absence of moisture.  The milling process is not a cooking step, so the flour that you purchase at retail in a bag is a raw product that must be cooked.  Surveys of raw wheat flour found very low counts of E. coli, less than 10 E. coli bacteria in a gram of flour, indicating that while low, there is a risk for harmful E. coli to be present in raw flour. 
[Reference: Sperber, W.H. 2007. Journal of Food Protection 70(4):1041-1053]


BCCDC recommendations for safe raw flour food-handling practices:

  • Do not eat or taste any raw dough (e.g., cookie, pizza or bread) or raw batter (e.g., pancake or coating) or any other product containing raw flour.  
  • Do not sprinkle raw flour on already cooked foods.
  • Recipes with no-bake cookies or other uncooked products should not be made with raw flour. (refer to the chart for alternatives)
  • Follow instructions to properly bake raw pie crusts, pizza dough and other pre-made foods made with raw flour.
  • Cook:  cook foods containing raw flour to a safe internal temperature of 74°C (minimum).  Check the internal temperature with a probe thermometer. 
  • Clean: wash hands, cutting boards, work surfaces, and utensils thoroughly with hot water and soap after contact with raw flour or dough products.
  • Separate:  keep raw flour products separated from ready-to-eat foods to prevent cross contamination and the spread of harmful bacteria that may be in the raw flour and dough.
  • Chill:  refrigerate or freeze products made with raw flour (e.g., pie tart shells) products after purchase or use.  Do not leave raw flour products (e.g., pie tarts shells or pancake batter) made in the home at room temperature for longer than two hours. Refrigerate or freeze them if they are not going to be cooked or baked that day. 

How can consumers limit their risk?  

Raw cookie dough, batter and pastry made with raw flour and raw eggs do have avoidable risks.  The best way is to cook before eating to avoid the risk of foodborne illness. You can also choose pre-cooked or pasteurized ingredients, like oats and pasteurized eggs, to limit the risk of illness.        
Avoid Eating
Choose instead

Raw cookie dough or no-bake cookies made with raw flour

Baked cookies, or no-bake cookies made with oats and other pre-cooked and ready-to-eat ingredients*


pasteurized eggs

Oats go through a steaming and toasting process, and are considered ready-to-eat and lower risk

Oats are whole grain, a good source of fibre, and a heart healthy choice

Raw cookie dough made with raw shell eggs Shell eggs may be contaminated with Salmonella. Pasteurized eggs, like pasteurized milk, have been heated to remove harmful bacteria.

*Pre-cooked and ready-to-eat ingredients include:  cocoa powder, barley flakes, wheat flakes, toasted nuts (whole, ground, or nut flours), puffed wheat or other cold cereal.

For more information on healthy food choices, consult BC dietitians by phoning 811, or visit the healthy eating website at 

SOURCE: Flour is Raw Food ( )
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