Is there really a difference between the two? TIA

I too would like to know? I am *assuming* that cake flour is finer? So, I tend to sift my normal flour 2-3 times for cakes. Not entirely sure if it makes any *noticeable* difference though. Sorry I didn't really answer your question

Cake flour is a little lighter. You can convert your all purpose flour to cake flour by using 3/4 cup flour with 2 TBSP cornstarch.

Cake flour has less protein and therefore is less likely to form gluten. Gluten makes breads hold into a bread shape but makes cakes tough.

Yes, What leah_s said. Down in the south the AP flour has a lower protein content then up north and if it is on the lower end may be subbed for cake flour.

will the cakes turn out lighter if i use cake flour?

yes

@ Leah, do you use cake flour for certain recipes and regular flour for thers?

At my cake supplier we have like four types of flour:

High protein flour (normally used for breads)
All-purpose flour
Medium protein flour (a.k.a cake flour)
Low protein flour (normally used to make those fluffy Chinese steamed buns)

@creative, yes. Most recipes use cake flour, but my chocolate calls for AP.

Which of the two is better for scratch recipes?

I use whatever is called for in the recipe. If I try it and don't like it, I may sub the AP for cake flour the next time. I wouldn't change a recipe until I've tried it once.

A cake made with cake flour will have a smaller, more tender crumb than a cake made with AP flour.

Additionally, all cake flour is bleached while not all AP flour is bleached.

The bleaching process causes the flour particles to have jagged edges which helps to hold butter heavy recipes in better suspension. I know this is true because I made the same all butter pound cake recipe using bleached and unbleached flour and there were obvious differences in the finished cakes.

The cake with unbleached flour had a visibly oily appearance in the lower half while the cake with bleached flour didn't. In the taste tests, the unbleached flour cake tasted oily in the lower section while the bleached cake was buttery throughout but not oily anywhere.

But if you can't find cake flour, bleached AP with cornstarch (to maintain the same volume of ingredients) is usually an acceptable substitution:

http://joyofbaking.com/IngredientSubstitution.html

Right now, King Arthur flour is advertising an unbleached cake flour blend but I've not tried it so I can't comment:

http://www.kingarthurflour.com/shop/items/unbleached-cake-flour-blend

Interesting article by Rose Levy Beranbaum on bleached vs. unbleached cake and AP flours with either cornstarch or potato starch:

http://www.realbakingwithrose.com/ingredients/

HTH

P.S. IMHO, the difference in texture (when using cake vs. AP flour) is a big deal. My twin sister really prefers the larger/more open crumb of a cake made with AP flour while I'm partial to the finer/tighter crumb of cake flour cakes.

Bleached vs. unbleached flour:

http://en.wikipedia.org/wiki/Flour_bleaching_agent

More than you ever wanted to know about flour:

http://www.thegrainmillwf.com/flour-comparison-information?SID=22fad07ceaec42fbe144a4aaae694c3c

My favorite cake flour recipe is Elvis Presley's Favorite pound cake:

http://cakecentral.com/recipes/7317/elvis-presleys-favorite-pound-cake

Thanks Jan H,Cheatize.

Use what the recipe calls for. If you want to try different flours to adjust the protein you can do that, but if the recipe is well-balanced to begin with you don't need to substitute cake flour for AP or vice-versa. My recipes use one or the other, but a couple call for a combination. If I use the wrong kind I can tell a difference in texture.

I use cake flour for layer cakes and it produces a moist, tender crumb...which is what I think cake layers should be. I do use AP for chocolate pound though.

Thanks for all the tips!!

One last questions- if a cake recipe calls for 3 cups of flour... should i assume its asking for AP or Cake flour

I would say if you want a lighter/fluffier texture use cake flour, if you want a denser cake try the AP flour. What the heck this is cake...do both ways and see which one you prefer.lol.

thanks cabecakes!!

Wow, thanks for the info... I use King Aurthur's Cake Flour, but it is SO expensive even at wholesale pricing I have started using Unbleached AP Flour adding cornstarch to it to make it "lighter," however, I never truly understood the difference between bleached and unbleached until I read the article you posted. Makes sense!