Let’s talk about flour in depth and get some things straightened up, so we can better understand the whole process of bread making!
Flour is an integral part of baking. All flour may look the same at a glance, but they could be very different to one another. The wheat variety, the protein content, the bran content, the region the grain is farmed and the season, the mill the flour was processed, the grind (particle size), the grinding technique etc. can all affect the final product. So this is why you can’t just substitute one flour with another and expect the same results!
If you are into serious breadmaking, it is worthwhile to spend some time demystifying flour. We all know that it is a carbohydrate, but there’s more to flour than just that. In this blog post, I will try to summarize some of my findings and learnings during my time as a culinary student, a professionally trained baker and a serious home baker. If you think anything is missing or incorrect please let me know in a comment. Feedback is always welcome!
Some terminology before we jump in…
Gliadin: A protein in flour that is sticky when wet. It is water soluble
Glutenin: A protein in flour that has elastic properties. It is water-insoluble
Gluten : Gliadin and Glutenin absorb water and form Gluten. Gluten is stretchy, sticky, elastic and tough. This is what helps strengthen a dough, which in tern helps create structure and rise in the final product.
When you hydrate flour(wheat flour) and leave for some time, the gluten will form. I am sure most of you have seen this in your autolyzed or bulked dough.
By kneading (or folding) we stretch these gluten bonds which will make then even stronger and elastic. We do the ‘window pane’ test to determine the gluten development in a dough.
Over kneading could break the formed gluten bonds which may cause the dough to collapse.
Wheat kernel: The grain that’s inside the inedible hull is called a kernel. The kernel has three distinct parts to it. Bran, endosperm and the germ which is depicted in the diagram below. Flour we use is mainly endosperm but can contain bran and germ in different proportions. We will talk about that later under Extraction
Endosperm: 83% of the kernel and contains most of the protein
Bran: The outer layer of the kernel. It has less protein and is very fibrous
Germ: It is the reproductive part of the grain or the embryo of the seed. This part contains several nutrients
Look how different these whole grains(kernels) look. They are all different wheat varieties. When milled into flour, they all look the same but they are actually quite unique in taste & strength
The word flour, in the baking world, is in general used to identify wheat flour, unless otherwise specified. Lets talk about some commonly available flour types in super market isles.
- Plain( all purpose flour)
- Bread flour
- Whole wheat flour (Wholemeal)
- Cake flour
Plain (all purpose flour)
This is the most common wheat flour available. All-purpose flour is produced my milling soft/weak wheat varieties that has less protein.
Most of the bran and germ are removed from the grain during the milling process and then refined to make all purpose flour. Protein content is around 9% – 11%.
If the packaging says enriched, then vitamins and minerals like thiamine, niacin, riboflavin and iron are added to the flour, which were taken away during the milling process. Remember bran and germ contain most of these nutrients.
All purpose flour is referred to as plain flour(outside North America), Maida(in India), refined flour, bread flour(Sri Lanka)
Bleached vs unbleached
Most all purpose flours are bleached unless the packaging says unbleached. Bleaching, is performed by treating the flour with a chemical(benzoyl peroxide, chlorine gas etc.) to speed up aging process (flour need to age to perform better and aging occurs naturally over time too). Bleached flour is whiter in color, has finer particles and is much softer to the touch. Unbleached flour on the other hand, is slightly darker, coarser to the touch and is slightly rough in texture. Almost impossible to differentiate unless compared side by side.
Bread products made with bleached flour are paler in color, softer in texture and usually has a better oven spring. The unbleached flour yield a more rustic product with a darker color.
What they are best suited for;
bleached all purpose : pancakes, muffins, waffles, pie crust etc.
unbleached all purpose: yeast bread, choux etc.
White bread flour is produced my milling hard/strong wheat varieties that has a higher protein content. It is sifted to remove most of the bran and germ so it consists of mostly the endosperm just like all purpose.
Protein content is around 12% – 13%. This high protein (gluten) content gives products extra strength that is advantageous when making crusty bread. Generic supermarket brands try to maintain consistency with their flour. This is achieved by mixing grains from different regions, farms and seasons to chive the same specification every time.
Bread flour can also be referred to as hard flour, strong flour, strong bread flour, depending on the region you live. Bread flour is best when making yeast bread, rolls, pizza etc. They produce a golden crust and a chewier crumb. Much easier to work with due to high protein(gluten) content.
All purpose flour can be used in place of bread flour but the results may vary.
eg: Bread made with all-purpose flour will have a softer crumb, may lack strength, have less oven spring and be lighter in color.
Wholemeal or whole wheat flour is made by milling the whole grain and thus contain all three parts of the kernel. Due to this reason it has a lower protein % and is coarser in texture. Hence it is difficult to build strength in baked goods which results in less rise (oven spring) and volume. Wholemeal products are denser (close crumb structure) yet much flavorful and very high in nutrients and dietary fiber.
Whole grain flour is best used in combination with a stronger flour to get the best of both worlds. Less kneading and more autolysing and folding is used when making wholemeal products.
A flour that is very low in protein, roughly around 7% – 8%. Because of this, there will be less gluten development and hence yields a very soft crumb. This is ideal for cakes & muffins as the name suggests.
Other flour types
Pastry flour – a finer wheat flour that sits in between all-purpose and cake flour in terms of protein content. Best for pie crusts, biscuits, scones, tart bases etc. This flour has moderate gluten (about 9%) which gives the product just enough strength to hold it’s shape yet produces a softer texture.
eg: Think about a good pie crust; it holds its shape and the filling but at the same time it breaks easily and melts in your mouth (crumbly).
Rye flour – A wheat variety often used in bread, mostly in conjunction with a stronger flour. Rye has a different type of gluten(secalin) and also in low percentage similar to barley. Because of this reason it is hard to develop strength in 100% Rye products. Also it contains pentosans(a type of carb) which causes glue like texture when hydrated. This is why rye is notorious of being sticky. Rye has a higher content of amylase than other wheat varieties. Amylase is the enzyme that helps break down carbs to simple sugars. Due to this reason, rye flour speed up yeast activity.
This is why we feed a lethargic sourdough starter with rye, when we want to rejuvenate it.
Spelt flour – Flour made from an ancient grain variety (dinkel wheat). Very high in protein and other nutrients. Could be found in different textures like, white, wholemeal or stone ground. The gluten in spelt has a slightly different molecular structure that it is more water soluble and could be easily destroyed by over mixing. So it is best used in no-knead breads and other products like cookies, biscuits, pancakes etc.
Corn starch (sometimes called cornflour) – Flour made from the endosperm of the corn kernel. Used as a binder or a thickener. Often confused with “corn meal” as in some regions corn meal is referred to as corn flour. Corn meal is a coarsely ground whole corn kernel, corn flour is finely ground corn kernel and corn starch(cornflour) is the finely ground endosperm.
Rice flour – Flour made by finely grinding rice grain. Red rice flour is obtained from red rice and white rice flour from white rice. Rice flour is low in protein, roughly around 6% and completely gluten free (no Gliadin and Glutenin). So it is ideal for cakes but not so much for crusty bread. But it is often used in gluten-free bread.
Semolina flour – It is a high-gluten flour made from hard durum wheat. usually available in different textures from coarse ground to fine. Mostly used to make pasta and couscous. It is great to be mixed with other flour for bread products. Coarse ground semolina is used in cakes.
Both rice flour and semolina are great for dusting bread, baguettes or pizzas to prevent sticking.
There are other flours like tapioca, potato, arrow-root, cassava flour etc. that are used in gluten free baking. Also coconut flour, almond flour, oats flour etc. are increasingly being used due to their high nutritional values. I will not be discussing those in this post to keep the context narrow.
Some mills are passionate about the wheat flour they produce and thus maintain their own brand. These flours are mostly sold directly to bakeries in bulk. They usually use wheat from a certain farm or a selection of farms and often mill them separately so they can tell which flour is from which farm. Due to the recent surge in bread making, home bakers showed interest in artisan/single origin flour. With this increased demand for good quality local flour, most mills now make their flour available to general public (for retail buying).
Different mills use different mechanisms to grind the flour. Stone-ground, roller-milled etc. They can also change the composition of the flour by including more bran and germ or the whole grain for that matter. The grind can either be coarse or fine gound depending on the demand or a special request. And when you store the flour for a long period of time, that changes the chemical balance in the grain too. The region the wheat is grown, the rain fall during the harvesting period and the season the wheat is grown all play a roll in defining the wheat and in-turn the flour it is turned into. Usually bakeries do test bakes(prior to mass production) whenever something related to their flour changes, to make sure the new flour performs the same in the existing recipes.
Important properties of flour
A mill usually maintains a spec for each flour it produces . Following are the most common pieces of information you can expect to find on a flour specification sheet.
- Protein content
- Extraction rate
- Ash content
- Falling number
Lets see what each of these mean and how it affects the bread making process. Remember all these factor along with the proteins % should be taken into consideration when selecting a certain flour or a flour blend for a specific bake. This is very critical for bakeries and not so much for regular home bakers unless you are serious about it..and you probably are, cos you kept reading thus far!
This is straight forward, and we did discus this before. This value tells you the amount of total protein in the flour and it doesn’t necessarily has to be the gluten %. Hard wheat varieties like Spring wheat contain more protein than winter wheat. Flour higher is protein, yield crusty breads with a chewier crumb. High protein flour is ideal for mixing with other low protein specialty flour like Rye, Spelt, Oats, Buckwheat or even wholemeal.
This is the amount of flour extracted during the milling process as a percentage of the wheat kernel. So 100% means the flour is whole grain (wholemeal). The lower the extraction rate, the more refined the flour is and the less of bran and germ in it. Extraction rate is a the major factor defining the Type of flour along with the protein content. France, Europe, Italy and America all have slightly different classifications when it comes to flour type.
eg: France use ash content to classify Type where as North America use the Extraction Rate
Lets look at some common flour Types based on the Extraction rate
T100 – Whole grain flour. If ground to a very fine texture, this makes great crusty bread. The store bought wholemeal is often coarsely ground and hence should be used with care. Very high in nutrition and yields a darker crust and crumb. Some may find this too strong for their palates.
Great for sourdough baking with less kneading and longer proofing time. Thirstier flour type and need a higher hydration. Due to high bran content, use care when developing strength. Use extra folds(coil fold or stretch & fold) and longer autolyse.
I often mix a finely ground whole grain flour with T85/T65 when making rustic sourdough bread
T85, T65 – Higher in protein % than wholemeal. Thirstier flour than refined(white) bread flour. Great for rustic bread. Require higher hydration. If you need flexibility or less elasticity, mix with a low protein flour.
I use this type for my sourdough rustic/country bread and focaccia.
T55 – Refined white flour falls under this category like white all-purpose and white bread flour that we use in everyday baking. Great for all sorts of baking. Yields a much lighter crust and crumb. Less notorious as most of the bran and germ are removed. Great for soft rolls, white bread, sandwich bread, French baguettes, laminated pastry.
T45 – Most pastry flours and cake flours fall under this category.
Other common flour types
T00 (pizza flour)- Italian classification. A flour made with hard wheat, so very high in protein and it is ground to a super fine texture. This allowed the dough to be stretched to extreme thinness without tearing. Perfect for pasta, pizza and crackers.
T150 – French classification. Corse ground wholemeal. 1.50% mineral content. Ideal for all artisan whole grain baking. Gives a darker crumb and a crispier crust.
As most organic material, flour contains water. Usually a small sample of flour is baked (dried) in the oven for 1 hour at 266˚F (130˚C) and the difference(loss) in weight is considered as the moisture content. Usually it is kept somewhere around 13-14% but could vary depending on the mill.
A higher moisture content will make the flour unstable at room temperature (storing) as organisms like bacteria could grow on them, making it’s shelf life shorter. Higher moisture also means there will be higher enzyme activity which could encourage break down of starch which is directly related to the falling number(described below)
A way to measure the mineral content of the flour. When you burn flour, all the organic material burn off leaving minerals which are called ash. Minerals come from germ and bran so essentially this tells us how much of the flour is actually bran and germ as a percentage. In other words how much ash is left when you burn 100g of flour. So, High Extraction flour has a higher ash content too.
This tells you how stable the flour is; meaning how active the enzymes are. The more active they are the faster the starches will be broken down. In other words, the flour will lose it’s gelatinous texture fast, making it less stable. This test is performed by cooking flour with water and placing the slurry in a test tube with a stirrer placed on top. The time it takes for the stirrer to reach the bottom, in seconds is the falling number. The shorter the number the more unstable (less gelatinous) the flour is.
Usually this test reveals what is referred to as the sprout damage. The rainy/wet weather condition during the final stage of the crop’s maturation could cause the enzymes to get activated resulting in premature (preharvest) germination. This means, some of the starch in the grain has already started to break down into sugars. This is the reason sported grains often has a lower falling number. Sported grains may be easier to digest but not great for mass bread production due to lack of strength.
See if you can spot the difference between these flour types…
Wholemeal vs white bread flour(usually T55). Whole grain is visibly darker and grainier to the tough. White refined bread flour has a much softer particles.
Both makes great bread. T85 gives a crispier crust and a darker color, due to high bran content. Also high in nutrition. Dough requires high hydration than white bread flour.
Whole grain flour is visibly darker and grainier due to the high content of bran and germ. T85 (High Extraction flour) has bran and germ too, but it is little less than wholegrain.
Store bought refined AP flour and Bread flour looks the same however, the main difference is the protein content(%)
Bleached flour is whiter in color and smooth to the touch than unbleached
Rice flour is visibly lighter in color (whiter) and grainier to the touch
Corn starch is used as a thickener but some times we use flour for that purpose, but look how different they are in texture
Whole grain Rye has a dark brown tint and the coarse grind is visible
Semolina flour is much finer than semolina. Semolina flour is great for crusty bread when mixed with other flour types. Commonly used to dust pizza bases and baguettes.
Knowing these things about flour, allows you to interchange or substitute flour in a recipe without affecting the final results or at least you’d know what to expect.
Do not hesitate leave you feedback and thoughts in the comments section below.