A couple of months ago I wrote about flour safety. Yes, I’m talking about flour that’s used for breading, baking and thickening. Eating raw (or undercooked) flour can be dangerous because it is a minimally process agricultural product. This means it is not
treated to kill bacteria, germs or other contaminants that may have gotten on the grain when it was in the field. The best way to reduce this risk is to thoroughly cook foods containing flour.

This column led to a few other questions. One reader wanted to know if this problem is only associated with wheat flour or could other flours or other whole grains be risky, too.

The short answer is YES. Other flours such as some gluten-free flours and non-wheat
flours are also potentially dangerous. Flour is an ingredient made by grinding grains,
roots, seeds, or beans into a powder. Wheat flour is the most common flour in the
United States, but there are numerous other varieties that may also be risky to eat raw. All raw flours, regardless of their source have a potential to be contaminated with harmful pathogens and should be treated with the same precautions as wheat flour.

The Food Standards Agency in the United Kingdom has issued a guidance regarding the safety of uncooked flour and flour products. They specifically identify several types of flour including wheat, gluten-free, corn, gram (from chickpeas) and rice flours as potentially risky.

According to the Whole Grains Council, caution needs to be taken with other raw grains, too. Raw grains and flours are not intended to be ready-to-eat. They have not undergone a “kill step” (such as boiling, baking, roasting or heat- treating) that would destroy risky pathogens. This isn’t usually a problem because most whole grains are hard and crunchy and not appetizing before cooking. But if this grain is made into flour, use care.

Oat flour and oatmeal is one grain that is safe to eat uncooked. In the process of making oatmeal, the oat grain is heated to stabilize the oat groats and then it is steamed to flatten into oatmeal. Thus, oatmeal and oat flour are classified as ready-to-eat. This is why “overnight oats” —oatmeal recipes where the oats are soaked with fruit and yogurt or milk overnight in the fridge—are safe to eat. One exception may be steel cut oats that are whole oats cut into smaller pieces. Steel cut oats are not always steamed or heated.

Getting ill from uncooked flour or flour products is rare as they are mostly used as an
ingredient in foods to be to be baked or cooked. But it is important to remember that
folks such as young children, those with compromised immune systems and older
people are more at risk because their immune systems may not be able to fight off
infections.

Another related question was regarding storage and how long can you keep flour.

All-purpose flour can be kept in a cool, dry place like a cupboard or pantry for six to 12 months. Storing them in food-grade metal, glass or plastic containers with tight fitting lids are the best options. Optimum storage temperature is 50 to 70 degrees. If you’re storing flour in your pantry, check it every couple of months for pests. It can be stored in the refrigerator for a year. If you have space in your freezer this is a good place to store all flours. All-purpose flour can be stored indefinitely in the freezer. (It’s also a good way to keep the bugs out.)

Since whole grain flours contain the vitamin and oil rich germ of the whole grains they will only keep in the pantry for three to six months (best quality). They are best stored in the refrigerator (six to eight months) or a year in the freezer.

A note: Make sure you bring frozen flour to room temperature before you bake with it.
Flour at freezing temperatures will discourage even the most vigorous yeast or baking powder.

Also, freezing does not destroy pathogens in flour. Even after freezing, care must be
taken to completely cook flour before eating.

References:

• University of New Hampshire Extension
• North Dakota State Extension
• CDC Food Safety: Raw Flour and Dough
• Michigan State University
• Whole Grains Council: Can You Eat Raw Grains?
• Food Standards Agency in the UK: Handling Flour and Flour Products Safely

Syracuse is a Family and Consumer Science team member and can be reached at N.C. Cooperative Extension, Brunswick County Center 910-253-2610 or by email at
clsyracu@ncsu.edu