The science of baking...a question in two parts. Scaling and "doctoring"

Discussion in 'Pastries & Baking' started by prettycakesnina, Jul 25, 2013.

  1. prettycakesnina

    prettycakesnina

    Messages:
    6
    Likes Received:
    10
    Exp:
    Culinary Student
    Hello everyone!  I'm posting this from New Zealand and very excited to find this site.

    I have a magic cake recipe that's been doing the rounds on the internet.  It was developed by a catering company that had to make 300 hundred cakes for an event and when baked is just average.  But after being frozen and refrigerated, it gets better over time.  It's a perfect carving cake, always gets great reviews from party guests.  It has a shelf life of 3 1/2 weeks. 

    Here it is:
    Thanks to Petalpop on Kiwicakes forum for posting this very popular chocolate cake that is best baked 1-2 weeks in advance and kept refrigerated.  Upon baking, tastes average, but after a few days it's amazing.  Fantastic texture and great for carving, this cake can be easily doubled and tripled in quantity.

    Allow to totally cool, then gladwarp several times and refrigerate or freeze.  Can freeze for up to 3 months.

    Petalpop has said about this cake: it will last Easy 3.5 weeks, the butter cream will go rancid before the cake!" I always use a whisk. And mostly bake in a 10" or will do 2 8" pans or a 9" and a 6""
    Instructions:

    Bring to the boil, then simmer for 5 minutes the following:
    3 x cups sugar
    2 x cups water
    250gm x butter
    1 x cup coco powder

    Allow to cool for 10 minutes, then add

    1 x teaspoon baking soda

    then alternate mixing in

    4 x beaten eggs
    3 x cups self raising flour

    Bake 180oc until cooked, allow to rest for 15 minutes then remove from tin, before the sugar sets it to almost make it impossible to get out of tin (do allow the resting time though for the cake to relax)


    Question 1.  I would like a recipe for this cake that will bake exactly a 6" x 4" high cake, but don't know how to convert the amounts.  Can anyone help?

    Question 2.  Given the very simple ingredients you see here, if I detest chocolate cake - how can I doctor this recipe or what can I replace instead of coco powder to make this into say any other kind of cake? e.g., caramel/apple/vanilla/coconut flavoured cake with the same shelf life, etc.

    I've asked the creator herself and she was unable to help. 

    Kind regards,

    Nina
     
  2. hokiegirl

    hokiegirl

    Messages:
    11
    Likes Received:
    10
    Exp:
    Other
    Have you tried to bake this cake using the recipe you noted? The recipe sounds a little off to me. Let me do some research and I will get back to you. I love white cakes and I'm always search for a good one!:)
     
  3. hokiegirl

    hokiegirl

    Messages:
    11
    Likes Received:
    10
    Exp:
    Other
    I found it! The author of the Magic Cake is French, Mabel Mendez. As suspected the recipe you noted was off. I have attached a link to the translated English version below.
    http://www.jocooks.com/bakery/cakes/magic-cake/
    The link to the blog of the author I have noted below. Mind you, it is in French. goggle will translate for you if you can not read it (I couldn't.) it's a pretty cool site to check out. She has you tube videos, pictures tutorials, and recipe variations!
    Http://decoraciondemabel.blogspot.com.es/2013/02/tarta-magica.html
    Have fun baking! If you bake this send me a message and let me know how it tuns out. I'm curious!
     
  4. prettycakesnina

    prettycakesnina

    Messages:
    6
    Likes Received:
    10
    Exp:
    Culinary Student
    Hi there hikiegirl and thank you for replying.  I have made the cake and it's so crazy, that I've called it a magic cake recipe. 

    I know it sounds off or strange, but the method is by following the instructions exactly as it says or it doesn't work.  It carves beautifully, has a fantastic texture and the taste is amazing for what it is.  No one believes it until they make it.  But you must let it mature in the fridge before eating.  It sounds strange, but the only thing I can say is try it and get back to me in a few weeks. 

    I want to keep the exact formula, but wanted to know how I can convert these amounts for a perfect 6" cake recipe.

    Thanks again xoxo
     
  5. prettycakesnina

    prettycakesnina

    Messages:
    6
    Likes Received:
    10
    Exp:
    Culinary Student
    (it's a fantastic cake for sculpting/carving).  The recipe you sent sounds amazing too, I might try it! xoxo
     
  6. petemccracken

    petemccracken

    Messages:
    3,401
    Likes Received:
    159
    Exp:
    Professional Chef
    Without knowing the exact amount the original recipe makes, it is impossible to convert.

    To create a conversion formula, one would have to have the volume the original recipe makes, i.e. diameter(s) AND heights and even then, the recipe may not cook up the same when changing pan sizes. Generally, a smaller diameter pan will result in a higher cake for the same depth of batter. I said generally, not always!

    Mathematically it is simple to figure out the ratio between two different volumes. Unfortunately, culinary does not always follow mathematical formulas.
     
  7. boar_d_laze

    boar_d_laze

    Messages:
    8,550
    Likes Received:
    202
    Exp:
    Cook At Home
    Tough to get a straight answer sometimes.

    The original recipe -- as supplied on the "translated" site -- is for an 8 x 8 pan.  8 x 8 x 2 is 128 cu in, and 128 cu in is close enough to 6 x 6 x 4's 144 cu in that the original amounts should be close enough.  

    FWIW, 6 x 6 x 2 is nominally considered a 6 cup cake pan, while 8 x 8 x 2 is 8 cups.   But I still think you should be alright.  The worst that can happen is that your 6 x 6 cake is only 3-1/2" high.  I don't think you're going to get much closer than that.  Why would you want to?

    BDL
     
  8. cheflayne

    cheflayne

    Messages:
    4,161
    Likes Received:
    530
    Exp:
    Professional Chef
    divide the original amounts by 3.5....I need to amend that as I just realized you wanted a cake 4" high, divide by 1.75 instead
     
    Last edited: Jul 25, 2013
  9. hokiegirl

    hokiegirl

    Messages:
    11
    Likes Received:
    10
    Exp:
    Other
    Hi again! Sorry I seemed like such a dope earlier, I was thinking too much about how the science of how all the ingredients worked together and what the finished product would look like.
    Today at work I got to thinking...

    There are several aspects of the chemistry of the chocolate cake being converted to a white cake.

    Fat content of cocoa powder
    You cannot simply replace the cocoa powder with flour, because it compared to flour, cocoa powder:

    Contains more fat (about 10-12 percent by weight, for grocery store brands; more for some premium brands up to about 25%)
    Is more acidic
    Is far, far more flavorful (okay, that part is not desired in a white cake)
    You should use slightly less flour than there was cocoa, to avoid adding flour by weight equivalent to the fat in the original recipe which would throw the balance off. I would suggest a half cup plus 2 tbls of flour instead of 3/4 cup of cocoa as a starting point.

    Flavor balance
    With the astringency of the cocoa removed from the recipe, the flavor balance may be too sweet. You might want to try reducing the sugar by about 1/4 cup - 1/2 cup.

    Acid and Leavening
    When you remove the cocoa, you are removing the acid that the baking soda was intending to react with.

    Therefore, you need to remove the baking soda, replacing it with baking powder which brings its own acid. You might need a slightly larger amount, as part of the weight of baking powder is the acid, so there is less leaving per unit than with baking soda. I would suggest an additional 1/2 teaspoon as a starting point.

    Boiling water
    The boiling water is specifically intended, to bloom the flavor in the cocoa. When you remove the cocoa from the recipe, you remove the need to use boiling water to enhance the chocolate flavor.

    Furthermore, the reason water is used rather than milk or another liquid is to interfere less with the perception of chocolate flavor. Therefore, you may choose to use another liquid like milk which will enhance the flavor and tenderness of your final cake.

    Flavorings
    For coconut, using coconut oil in lieu of butter, and coconut milk in lieu of water, and adding coconut extract should do the trick. The recipe should also be able to carry a small amount of shredded coconut if you choose, although that will change the texture.

    For vanilla, try milk instead water. Add vanilla extract.

    For lemon, start as with vanilla, and add lemon zest to the batter (and maybe lemon extract), and possibly, should you choose, a touch of yellow food color. I would not add lemon juice as it has a profound effect on the chemistry; instead I would make a nice lemon icing or glaze that has the tartness.

    Conclusion
    I think this recipe is meant to be what it is. In my opinion there are too many things to consider here... And by making all the ingredient substitutions I think the method will change as well.

    However, I am intrigued by your recipe and can't wait to try it!
     
  10. boar_d_laze

    boar_d_laze

    Messages:
    8,550
    Likes Received:
    202
    Exp:
    Cook At Home
    No Layne.  You're not only backwards but your factoring is way off.

    If any change were needed at all, the amount of the original recipe needs to be increased, not decreased. 

    8 x 8 x 2, the size of the original recipe pan, is 128 cu in, while 6 x 6 x 4, the desired size, is 144 cu in.; which would mean the original recipe would have to be increased by a factor of 1.125, which is to say the original recipe would need to be increased by one eighth.

    Using the nominal difference in recipe volumes for pan size, an 8 x 8 x 2 recipe is 8 cups, while 6 x 6 x 2 -- a standard cake pan size is 6 cups.  6 x 6 x 4, the desired size is twice 6 x 6 x 2, and nominally is 12 cups.  That means the original recipe would have to be increased by a factor of 1.5, which is to say that the original recipe would need to be increased by one half.  

    In my opinion, the original recipe does not need any adjustment to move from an 8 x 8 pan to a higher 6 x 6 pan, so long as 4" is not a strict requirement.  If however, I wanted to increase the recipe amount slightly, I'd do it by adding another egg.   If I were using the 4 egg recipe, I'd scale up by 25% (1/4) so as to use 5 eggs -- since eggs are the hardest thing to parse; and if using the five egg recipe, I'd use six eggs -- a 20% (1/5) increase 

    People frequently talk about baking as though exact proportions were critical.  However, that's not how recipes are "perfected" and written; it's not how food works in general; and there's almost always a fair amount of wriggle room.  The trick is not to exceed it.   If you're off a 1/4 cup flour, or use jumbo eggs instead of large, it's not going to make much difference.

    Also, Hokiegirl went through a lot of good reasoning to reach a wrong conclusion.  There are ways to make the "magic cake," or at least something similar enough to have the same name, with all sorts of flavor profiles by beginning with the non-chocolate recipe at the top of the already linked page and adding grated rind, extracts, soaking with wine or booze after baking, etc.   For instance, a light soak with lemon, basil, rum syrup would be very good and very different. 

    BDL
     
    Last edited: Jul 26, 2013
  11. cheflayne

    cheflayne

    Messages:
    4,161
    Likes Received:
    530
    Exp:
    Professional Chef
    The recipe said it produces two 8" pans, so that is what I based my backward, way off factoring on.
     
    Last edited: Jul 26, 2013
  12. petemccracken

    petemccracken

    Messages:
    3,401
    Likes Received:
    159
    Exp:
    Professional Chef
    Um, specifically, the recipe says
    But neglects to indicate the height of any of those pans. If we calculate the volume per inch of height, we arrive at
    • 10" pan = 78.5 cubic inches/inch
    • 2-8" pans = 100.5 cubic inches/inch (50.25 cubic inches/inch for each pan)
    • 9" plus 6" = 91.9 cubic inches/inch (63.6 cubic inches/inch for the 9" and 28.3 cubic inches/inch for the 6" pan)
    It is fairly obvious that the heights will differ, mathematically, the relative heights will be:
    • 10" = 1 (reference)
    • 2-8" = 0.78 (calculated) (a single 8" would be 1.6)
    • 9" plus 6" = 0.85 (calculated)
    If a single 6" pan were used, the ratio will be pretty close to 2.8.

    Converting the mathematical calculation to something more closely useful, let us assume that the 10" pan produces a 2" layer, then
    • 2-8" pans will produce 2 - slightly more than 1 1/2" layers
    • 1-8" pan will produce 1- 3 1/4" layer
    • 9" plus 6" will produce layers that are just under 1 3/4"
    • 6" pan will produce a layer almost 5 5/8" high
    Now, all of the above is mathematical and may have little to do with what actually happens when baking /img/vbsmilies/smilies/crazy.gif

    First, the above assumes that the recipe author was talking about circular cake pans, not square.

    Second (and I'm fairly confident that this is an invalid assumption because of structural integrity), cake batter rises inversely proportional to the area of the pan.

    Thirdly, the initial depth of batter has no affect on the ability of the cake to rise (again, I believe this is invalid because of structural integrity)

    I've enjoyed the mathematical exercise but I am far from confident the mathematical results will bear any resemblance to the practical results.

    It really would be wonderful if an experienced cake baker would chime in with a practical approach.

    Oh, from the above, something close to 3/4 of the original recipe would appear to be a reasonable approximation for the first try at a 6" round by 4" high layer.
     
  13. laurenlulu

    laurenlulu

    Messages:
    612
    Likes Received:
    75
    Exp:
    Professional Chef
    Wow.. As an intuitive baker the math is overwhelming to me. 

    Makeprettycakes, I know this doesn't address your question but as someone who has done pastry for a long time I have to offer some advice. I strongly suggest you don't try to get a 4 inch deep product. It's very difficult to avoid overbaking the outside before the inside is cooked and if you lower the temp to try to compensate it will make your batter's leveaning properties change - it will bubble over the edge and your finished product's texture will be different.
     
  14. boar_d_laze

    boar_d_laze

    Messages:
    8,550
    Likes Received:
    202
    Exp:
    Cook At Home
    From the recipe prettycakes and I quoted and linked:
    If that sounds like a defense, it isn't.  

    I mistakenly assumed that Layne was referring to this recipe and not the one originally linked by the hokiegirI, and apologize for not asking before responding so pedantically.

    After actually reading both recipes I realize that -- other than the use of the word "magic" -- the two have nothing in common.  If I'd looked before I posted I wouldn't have used prettycake's recipe for my figuring, nor would I have needed to ask Layne.  So, I was not only rude but careless -- doubly wrong. 

    The correct conversion factor for going from 10 x 10 x 2 to 6 x 6 x 4 is 1.4.  In order to get an exact scale from 10 x 10 x 2 to 6 x 6 x 4, the quantity amounts in the original recipe should be multiplied by its reciprocal, 0.7.  But I stand by the point that quantities in baking recipes intended for home bakers are more flexible than the conventional wisdom that "baking is an exact science" would have it.  So my suggestion would be to use 3/4 instead of 0.7 if it's easier, and round the scaled quantities to the nearest convenient measure.

    However, if the 10 x 10 pan in question only made a 1-1/2" cake, no scaling is necessary, despite the recommendations on the recipe itself. 

    Pete is right -- As a general rule, recipes amounts don't always scale proportionally, and  baking specifically is even crankier. 

    Laurenlulu is right as well.  Making a 4" deep cake is risky.  Better to make two 2" layers, fill them with jam and stack them. 
     

    Apologies again,

    BDL
     
    Last edited: Jul 26, 2013
  15. cheflayne

    cheflayne

    Messages:
    4,161
    Likes Received:
    530
    Exp:
    Professional Chef
    The recipe that I was referring to was the one posted by the original poster, makeprettycakes. It was to her question about scaling that I offered my solution.

    I agree with laurenlulu and also think it would be a mistake to try and go for a 4" high cake for the very reasons that she mentioned. However trying to make a 4" high cake could be a good learning experience with a worst case scenario of being out a few bucks spent on ingredients.

    I always remember the words of one of my mentors who told me not to worry about my mistakes, but to instead learn from them from because many times they teach us much more than our successes and that you aren't really a chef until you have made a few thousand mistakes.
     
    Last edited: Jul 27, 2013
  16. laurenlulu

    laurenlulu

    Messages:
    612
    Likes Received:
    75
    Exp:
    Professional Chef
    I very much agree. A few chefs I've worked with don't understand that while baking is science it is not exact, there is flexibility as long as the approximate ratios stay intact.

    That's how I can seemingly dump ingredients together and "magic happens", as I've been told. Some people need the rigidity of a recipe to feel comfortable and guided but I am living proof that it is by no means necessary to achieve a wonderful finished product.

    BDL, I am impressed by your integrity. You apologized when you believed that you were mistaken, that says a lot about who you are :)
     
    Last edited: Jul 27, 2013
  17. prettycakesnina

    prettycakesnina

    Messages:
    6
    Likes Received:
    10
    Exp:
    Culinary Student
    Please do, I would love to hear your opinion on it! Your post has been amazing and so helpful! xoxo
     
  18. prettycakesnina

    prettycakesnina

    Messages:
    6
    Likes Received:
    10
    Exp:
    Culinary Student
    This post is so great, my head is spinning. 

    I'm going to print this out and have a good close look at the math so that I understand it and it sticks. 

    I'm going to have a go with the different options suggested and test the recipe out.  The reason I'm after a single 6" recipe is because I want to give it out and have people bring me their baked 6" round cakes with the least amount of hassle.  Is there ever a time you would bend your own rules and bake a tall cake?

    I currently use a different recipe and bake six cakes in one go - another bad habit I suppose!  But that's why I'm here, I want to learn to bake properly. :)
     
  19. aileen

    aileen

    Messages:
    1
    Likes Received:
    10
    Exp:
    At home cook
    What an interesting recipe!

    I followed both links posted by the OP. I enjoyed Mabel Mendez' blog (Spanish, not French, by the way). It's a a traditional Romanian dessert called Prajitura Cremes inteligent (Intelligent Cream Pastry).

    It reminds me of Filipino custard cake, but with an extra layer.
     
  20. hokiegirl

    hokiegirl

    Messages:
    11
    Likes Received:
    10
    Exp:
    Other
    My bad once again, sorry. I hope everyone got the help they needed here. The math sure was for thoughts :).