By Abbey Thiel
When looking for flour, many people seize the bleached bag with out a second thought. It’s what our mom at all times purchased. It’s brilliant white. It’s what we’re used to working with.
However, in the event you paused for only a second, you’ll discover a small part of unbleached flour on the identical cabinets.
Which makes you marvel, have you ever been shopping for the mistaken flour all of your life?
Why is flour bleached?
As you’ll have guessed, bleaching is the strategy of turning flour that intense white coloration. Much like what bleach does to your garments.
Naturally, flour has yellow tinted molecules referred to as carotenoids, which give a barely cream coloration to the crop. Carotenoids are the identical pigment molecules present in brilliant orange carrots.
Traditionally, customers didn’t like this yellow-colored flour. They most well-liked the completely white variety. Fortunately, over many months of storage, flour will flip from yellow to white because it’s uncovered to oxygen in the air.
The one drawback is, flour millers don’t wish to maintain onto their product for a number of months and even as much as a yr. It’s costly and requires a variety of area.
Millers needed to discover a technique to get their flour on the market instantly and see a fast return in revenue.
And if oxygen was the key to this transformation, why couldn’t the transition from yellow to white be accomplished chemically and instantaneously? Why look ahead to bleaching to naturally happen?
So, what’s this bleaching course of entail?
Chemical bleaching of flour was first launched in the 1906 Pure Meals and Drug Act. This act decided a list of bleaching brokers that have been deemed secure and the record continues to be added to (or retracted from). Choices embody compounds like nitrogen peroxide, chlorine gasoline, chlorine dioxide, nitrogen trichloride and benzoyl peroxide.
These bleaching brokers are often added on to freshly milled flour to yield a white product in only a day to 2. A lot sooner than naturally bleaching flour for a number of months, making bleached flour way more economical.
Inside flour, the carotenoids or these yellow-colored molecules, are being transformed into colorless compounds by the bleaching agent. This ends in a wholly new molecule that’s not a carotenoid anymore.
For the nerds (like me!) on the market, chemically what’s occurring is the bleaching agent assaults the place the carotenoids have double bonds. Carotenoids are massive molecules with a system of quite a few double bonds, so it is a fairly simple job for the bleaching agent to perform. The yellow pigment is destroyed because it’s been transformed into one other compound.
However, there’s extra.
Some extra benefits of bleaching are that it helps dry the contemporary flour sooner, results in a finer grain, and extends the shelf life.
Unbleached flour remains to be bleached… simply naturally.
The title “unbleached flour” isn’t precisely becoming.
One of these flour remains to be bleached to achieve an off-white coloration. It simply makes use of the gradual strategy of exposing the flour to oxygen over many months.
Slightly, the time period “unbleached” is a means for the millers utilizing the pure bleaching course of to distinguish themselves from flours which can be chemically bleached and might be bought at a lot decrease costs.
Is one higher than the different for baking?
Chemically bleached flour is extra user-friendly for baking than unbleached flour. That’s as a result of bleaching does extra than simply end in a much less coloured product.
Many bleaching brokers like chlorine dioxide and chlorine gasoline are often known as maturation agents. These compounds alter the construction of proteins in the flour by a response often called oxidation. Primarily, the maturation agent modifies the proteins in order that they now work together with one another. The proteins make extra connections and type massive networks. In baking, this is named creating the gluten or forming the gluten community.
Plus, this small alteration to the proteins makes the dough less sticky and easier to handle. That is key for meals producers which can be churning out 1000’s of baked items a day and handy for us residence bakers too. It additionally offers baked items a greater quantity and texture.
The one time unbleached flour could be advantageous is if you would like a dense, compact loaf.
Chemically bleaching flour usually does extra than simply lend the product a white coloration. It’s essential for oxidizing, or chemically altering, proteins in order that they’re able to type robust gluten networks whilst you’re baking.
Unbleached flour doesn’t undergo this chemical course of. As a substitute, flour might be naturally bleached by exposing it to air for a number of months, however this course of is gradual and inconsistent.
So the subsequent time you’re stocking up on all of your baking elements, you’ll be able to strategy that flour part with confidence, understanding precisely what you get.
Abbey Thiel | Linkedin
SMF Weblog Author
Abbey found that meals science was an actual main whereas attending College of Wisconsin-Madison, and shortly transferred into the division. After graduating with a B.S. in meals science, she determined to remain in Madison to pursue her PhD. Her analysis explores the fats community discovered inside ice cream, and sure, there’s a number of ice cream events! If not discovered sitting at a microscope for prolonged quantities of time, Abbey enjoys the nice Midwestern sport of log rolling (Google it) and laughing actually loud. She can also be very busy passing on her ardour for meals science to her two-year-old niece, whose favourite coloration is bacon and has hopes of rising as much as be soup.