Safe handling of flour
Flour comes from grain, which is grown in fields. In the fields, the grain may become contaminated through direct contact with bacteria from:
- soil
- water
- animal waste
Flour is a raw ingredient that is meant to be cooked before it is eaten. Common “kill steps” that are often used during food processing will kill bacteria that may be present in raw flour. Kill steps include:
- frying
- boiling
- baking
- roasting
On this page:
- Health risks
- Safety tips when handling flour
- Best practices for cooking with flour
- Who is at risk
- How we protect you
Health risks
Raw flour may be contaminated with harmful bacteria such as E. coli. People infected with E. coli can have a wide range of symptoms.
Some people do not get sick at all, although they can still spread the infection to others. Others may get an upset stomach or become seriously ill and need to go to the hospital.
Common symptoms of E. coli can appear within 1 to 10 days after contact with the bacteria. Symptoms include:
- nausea
- vomiting
- headache
- severe stomach cramps
- watery or bloody diarrhea
Most symptoms go away within 5 to 10 days without needing to see a health care provider.
Safety tips when handling flour
Follow these tips to avoid illness when handling flour:
- bake or cook items made with raw dough or batter before eating them
- do not taste raw dough, batter or any other product containing uncooked flour, such as cake mix, as eating even a small amount could make you sick
- do not use raw flour in non-baked goods or a non-baked product, such as children's play-dough
- always use hot water and soap to wash any:
- bowls
- utensils
- surfaces that flour was used on
- wash your hands with soap and warm water immediately after touching:
- flour
- batter
- raw dough
Best practices for cooking with flour
When cooking with flour, you should:
- avoid cross-contamination by:
- keeping raw foods, including flour products, separate from other foods while preparing them
- using separate bowls, measuring cups and utensils to keep flour, raw dough and raw batter separate from ready-to-eat food
- bake or cook items that contain flour, including flour used for thickening
- not add flour to foods that will not be cooked, such as milkshakes and ice-cream mixes
- follow package directions on products such as cake mixes for proper cooking temperatures and specified times
Who is at risk
While anyone can become infected with E.coli, certain groups of people are more likely to get sick. These include:
- older adults
- young children aged 5 and under
- people with weakened immune systems
For these people, symptoms may be more severe.
How we protect you
We are committed to food safety. Health Canada (HC) creates regulations and standards for the safety and nutritional quality of foods sold in Canada. Through inspection and enforcement activities the Canadian Food Inspection Agency confirms that food sold in Canada meets HC’s requirements.