Over the past several years, there have been outbreaks from the consumption of raw flour and boxed cake mixes as well as recalls of flour. Flour is a raw agricultural product that can become contaminated with Salmonella and pathogenic Escherichia coli (E. coli) while the grain is growing in the field or during processing. These bacteria can survive in flour for a long time, even at room temperature. They are killed when flour is baked or cooked.
There are some myths about flour that are found on the internet. There are claims that you can heat treat flour by microwaving or baking it to kill pathogens. Both are myths. The only way to reduce the risk is to cook or bake flour recipes to required times and temperatures.
Here are simple things that you can do to reduce the risk:
- If you put flour in a canister for storage, tape the product label with dates and lot numbers to the canister. This way, if there is a recall you will know if it is for your brand of flour and what to do with it. In most cases, it will need to be thrown out.
- Follow directions on recipes, baking cookie dough or boxed mixes for baking or cooking temperatures and times. Use a food thermometer to take temperatures.
- Separate and store flour and eggs so that they don’t contaminate other foods, particularly foods that are not cooked prior to eating.
- Refrigerate cookie and pastry dough in a refrigerator set at 40º F or below. Invest in an appliance or refrigerator thermometer.
- Avoid eating, tasting and playing with products made with flour and/or eggs. This includes cookie dough, brownie mix and homemade play dough.
- Don’t use raw cookie dough in ready-to-eat ice cream. Commercially produced cookie dough ice cream has been treated to kill pathogens that can cause illness.
- Always wash hands thoroughly with soap and running water after handling flour and raw dough mixes.
- Wash utensils, bowls, baking pans and cutting boards with warm to hot soapy water and rinse well.
According to the Home Baking Association, these are the final cooking temperatures for some flour-based foods:
Cheesecake – 150º F, but the temperature will rise to 160º as it cools
Meringue pies and quiche – 160º
Meat, cheese or poultry-filled bread – 165º
Soft rolls – 190º
Crusty bread – 210º
Cakes, quick breads and scones – 200º – 209º
For more information about cooking temperatures, visit HomeBaking.org.
Article and photo courtesy of Ann Hamilton, UNH Extension
