Showing posts with label food science. Show all posts
Showing posts with label food science. Show all posts

February 12, 2012

The Science of 'Wait, What?': Red Velvet Cupcakes Edition

Red velvet, red velvet, why did you not fail as miserably as your vanilla and chocolate peers? In fact, why did you excel at high-altitude when your vanilla and chocolate counterparts failed?

Below are pictures of my first attempts at the Hummingbird Bakery Cookbook's vanilla, chocolate, and red velvet cupcake recipes at high-altitude. That is, these are pictures of control experiments -- I made no alterations to the original recipe because I wanted to see what the unaltered recipes would produce at high-altitudes.

Here they are:

1) Hummingbird Bakery Vanilla Cupcakes, Unaltered First Batch:


Ah yes, the oft-cited puddles of goop. Despite the poor iPhone photo, you can see that these 'cupcakes' are liquidy, overexpanded, and collapsed.


---

2) Hummingbird Bakery Chocolate Cupcakes, Unaltered First Batch:


Significantly better, but with an undercooked pallor and cratered cupcake tops. Again, pardon the grainy iPhone picture.


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3) Hummingbird Bakery Red Velvet Cupcakes, Unaltered First Batch:


Deceptively perfect, had it not been for the old sea-level photo I dug out. A little puffy and bloated with ugly cupcake tops, but perfect crumb and flavor.

They seem to be getting better and better, no?

When I set out to adapt the Hummingbird red velvet recipe, I was incredibly nervous for several reasons. First things first -- not only are red velvet cupcakes my favorite recipe EVER, they also happen to be the Hummingbird Bakery's signature cupcake. According to my British friend Kiron, with the exception of the Hummingbird Bakery, red velvet cake hardly exists anywhere else in England. So pressure was on!

I was also nervous because the recipe for red velvet cupcakes contained two ingredients that I had yet to work with at high-altitude: buttermilk and baking soda. According to Joy of Baking (my favorite online source), baking soda is about four times as strong as baking powder. Yerp. A leavening agent that is four times stronger than baking powder? Scary stuff, considering that baking powder has always caused me such pain in my previous experiments.

Okay, but wait. Recall that leavening agents tend to work better at high-altitudes due to fact that there's less atmospheric pressure at higher altitudes. This decrease in atmospheric pressure allows the agents to produce more leavening gases, simply because there is less weight (that is, air pressure) pushing down and preventing these gases from forming and rising up.

So if leavening agents work extraordinarily well at high altitude, and if baking soda is way stronger than baking powder, why didn't I end up with the puddles of goop like I did with the vanilla cupcakes?

I figured it was time to compare all three unaltered, original, sea-level Hummingbird Bakery recipes:


In my previous post, I was struggling to define red velvet cake. A baker at Portland, OR's Saint Cupcake Bakery told me that it was a combination of vanilla and chocolate flavors. Now that I've finally taken the time to examine the three recipes, I see that this description was definitely wrong. According to the Hummingbird Bakery Cookbook's recipes, vanilla and chocolate flavors are more similar to each other than red velvet is to either flavor.

There were the differences I mentioned previously -- red velvet's use of baking soda instead of baking powder and its use of buttermilk instead of whole milk. But looking at the chart above, I see more differences: red velvet cake uses more butter and more flour.

The use of more butter is interesting -- according to Susan Purdy's Pie in the Sky: Successful Baking at High-Altitudes, high-altitude bakers are often ill-advised to "reduce the fat in rich cakes and cookies at high elevations." The rationale behind this is that fat (in our case, butter) coats the protein/gluten in flour and weakens it. At higher elevations, when liquids evaporate faster, the residual higher concentrations of fat and sugar may weaken the cell walls too much and cause the cake to collapse. However, Purdy suggests an alternative to this reduction -- instead of cutting the fat (which can compromise flavour), you can strengthen the batter by adding flour.

Which brings us to the red velvet's high flour content. The table above shows that red velvet has the highest flour content of all three recipes above -- that is, red velvet cake batter is heavier than that of vanilla or chocolate. For instance, the vanilla recipe only has 16 tablespoons (1 cup) of flour, while chocolate contains 16.5 tablespoons (3/4 cup plus 2 tablespoons of flour combined with 2.5 tablespoons of cocoa powder). Both recipes are then dwarfed by red velvet, which comes in with 19 tablespoons of some sort of flour mixture (1 cup plus 2 tablespoons combined with 1 tablespoon cocoa powder). No wonder the Hummingbird Bakery vanilla cupcakes recipe only yields 10 while the red velvet recipe yields as much as 14 cupcakes! It is this extra flour that helps add structure to the red velvet cupcakes, preventing it from rising too quickly and collapsing in on itself. Bear in mind that cocoa powder is also a strengthening agent and heavier than flour; while the chocolate cupcake recipe accounts for the addition of cocoa powder by subtracting some flour, the red velvet cupcake recipe does not.

Well, well, well. It might not explain why the red velvet cupcake tops are uglier here than they are at sea-level, but it's certainly a start.

January 19, 2012

The Science of Nothing: Chocolate Cupcakes Edition

Not gonna lie. My previous discovery -- that chocolate cupcakes needed less baking powder than vanilla cupcakes at high altitude, proving my hypothesis completely wrong -- had me stumped.

I started out by consulting the usual sources. But to be honest, they weren't that much help. For starters, my go-to cookbook, Susan Purdy's Pie in the Sky: Successful Baking at High Altitudes, didn't have a paragraph dedicated to any chocolate products, let alone cocoa powder. Joy of Baking, a normally reliable internet source, had nothing except for stating the opposing fact that more leavening agent is sometimes used in recipes containing cocoa powder to offset the powder's drying and strenghtening affect in the finished product.

My last hope lay with Paula Figoni's How Baking Works. The culinary textbook has an entire chapter dedicated to cocoa and chocolate products, with a pretty lengthy section on the functions of such products. But aside from agreeing with the Joy of Baking and confirming that indeed, cocoa powder is an extremely effective drying and structuring agent, there was nothing I could use to help solve the mystery.

I guess I suffered the throes of food blog writer's block, because for the next few days, I pushed aside this mystery and focused on other things. Despite the fact that I left Ms. Figoni's textbook open in the middle of my coffee table to a page labeled "Handling Chocolate Products", I pretty much ignored it. I watched Portlandia on my laptop, using the open pages before me as a sort mat protecting my legs from the heat of my computer. I played with my new Canon Rebel XSi, taking close-up pictures of the open textbook, wondering how Coco from Roost produced significantly more beautiful photos, despite the fact that we used the exact same camera. I reread the first book of the Hunger Games series, even though I had already read it twice within the last month.

My attention returned (rather guiltily) to the open textbook when Katniss Everdeen started dipping her bread rolls in hot chocolate. Out of the corner of my eye, I saw a section titled "Tempering Chocolate". I had previously ignored this section because I didn't believe tempering to be relevant to my baking experiment. Tempering, the process of controlling the melting and the cooling of the chocolate before it sets, is a process strictly for handling solid chocolate -- or so I thought.

The paragraph began,

"When chocolate is melted and allowed to cool on its own, it takes a while for it to set."

Wait a second.

I must confess that I had been a little too optimistic in my previous post. Recall that I declared the - 3/4 reduction in baking powder the winner of my experiment because it produced perfectly risen and domed cupcake tops:


Looks good right?

But see, above is a photo of what the cupcakes looked like fresh out the oven. That is, I put down the tray, took off my oven mits, and snapped a photo. They looked perfect, but warm and bloated from the hot oven air.

Because this is what happened when they cooled:


The cupcakes sank! Yes, they cratered. Like every adjustment failure I've made before. Even with the SIGNIFICANT reduction of baking powder.

See this?


Sure, not flat. Vaguely, ever-so-slightly domed. Definitely not the nice, puffy dome that first came out of the oven.

Gah.

As a matter of fact, almost every cupcake version I had tried, regardless of how much or little I reduced the baking powder, cratered like the unaltered sea-level recipe did when they cooled:


Sure, some reductions fared better than others. The top photo of the cupcakes with lesser reductions (- 3/8 and - 1/4) were more cratered than the bottom photo of the cupcakes with the greater reductions (-1/2 and -3/4):


According to How Baking Works, when chocolate is melted and allowed to cool on its own, it takes a while to set. When it does finally set, several things could go wrong with the chocolate -- dull appearances, gritty and crumbling textures, gray and white streaks she ominously calls 'fat blooms'... the list goes on.

Figoni writes that all these things could happen because of the way cocoa butter in chocolate solidifies when it cools on its own. Cocoa butter is polymorphic, which means that it can solidify into crystal shapes with different properties. The crystal shapes have different melting points, densities, and stabilities. When left to cool on its own devices without proper tempering, unstable crystal shapes usually form. These crystal shapes cause dull and "soft" chocolate.

"Soft" chocolate? Maybe the kind that would cause my cupcakes to sink and become unstable?

Certainly sounds like it to me. More specifically, it sounds like I need to "temper" my chocolate cupcakes. That is, I need to control the setting and the cooling of the chocolate in the cupcakes.

The main tool used for tempering chocolate is temperature; Paula Figoni even provides specific temperature ranges allowing readers to see which temperature leads to what sort of crystal in the chocolate. This is especially relevant because one of the things that remained consistent during my earlier experiment reducing baking powder is that none of the cupcakes looked like they were fully cooked. The Hummingbird Bakery Cookbook states that fully cooked cupcakes have tops that "spring back when touched"; however, all four rounds of cupcakes in my earlier experiment had tops that remained sticky and deflated from the touch.

This was normally a sign of being undercooked.

Indeed, almost all high-altitude tips recommend increasing the oven temperature by a few degrees. The idea behind this is to use a higher temperature to "set" the structure of baked goods before they overexpand and dry out -- especially since the propensity for baked goods to overexpand and dry out at high-altitude is significantly greater since leavening and evaporation proceed much more quickly. Recall that the high-altitude version of vanilla cupcakes needed a temperature increase of 50 (F) degrees from the original recipe before they actually cooked properly.

So, long story short, it sounds like the answer to my problem could be fixed by controlling the chocolate cupcakes' "setting" process by increasing the recipe's oven temperature.

Hm.

January 16, 2012

High-Altitude Hummingbird Bakery Chocolate Cupcakes, Pt. 1: Decreasing Baking Powder

In my last post, I discovered that the sea-level recipe for chocolate cupcakes fared significantly better at high-altitude than that of the vanilla cupcakes. The additional cocoa powder in the chocolate cupcakes recipe provided the extra structure that was needed for the vanilla cupcakes to retain their form. For this reason, I decided to skip messing with the flour and cocoa powder quantities in the original chocolate recipe, and just dive right into messing with other problematic ingredients like baking powder.

Baking powder -- or, any leavening agent really -- is the bane of the high-altitude baker's existence.

Recall that leavening gasses like air, carbon dioxide, and water vapor expand fast in higher elevations. Leavening agents like baking powder create these gasses in the cake's batter. When these leavening gasses expand quickly, cakes rise far too quickly and proceed to sink in the oven or during the cooling process. These gasses expand much faster because air pressure lessens at higher altitude -- that is, there is less air pushing down on the cake batter, causing it to rise more easily. So, essentially, the higher the elevation, the lower the air resistance, the more easily the baking powder will work.

Because the Hummingbird Bakery Cookbook use a lot of baking powder in its recipes, I was not surprised to find that I had the same problem with the vanilla and chocolate cupcakes recipes: the cakes, when cooled, would be slightly sunken in. They looked like mini-craters. This is a result of the rising-too-quickly problem I described above. I was able to fix this problem during my vanilla cupcakes experiment by reducing the baking powder, and I hoped the same solution would fix my chocolate cupcakes.

For the vanilla cupcakes, I eventually ended up reducing the amount of baking powder in the recipe from 1.5 teaspoons to 1 teaspoon. A full half-teaspoon reduction -- basically subtracting a third of what was needed in the sea-level recipe. That's pretty substantial if you ask me. I figured that the chocolate cupcakes would NOT need such a dramatic reduction, especially because the cocoa powder in the recipe provided a stronger batter structure that the vanilla cupcakes lacked.

So, with this hypothesis in mind, I started by reducing the original recipe by a rather conservative amount of a quarter (1/4) teaspoon of baking powder. Recall the original ingredients quantity for the chocolate cupcakes:
  • 3/4 cup plus 2 tablespoons all-purpose flour
  • 2 1/2 tablespoons unsweetened cocoa powder
  • a scant 3/4 cup sugar
  • 1 1/2 teaspoons baking powder
  • a pinch of salt
  • 3 tablespoons unsalted butter, at room temperature
  • 1/2 cup whole milk
  • 1 egg
  • 1/4 teaspoon pure vanilla extract
My amendment (in bold) is as follows:
  • 3/4 cup plus 2 tablespoons all-purpose flour
  • 2 1/2 tablespoons unsweetened cocoa powder
  • a scant 3/4 cup sugar
  • 1 1/4 teaspoons baking powder (1.5 - .25 = 1.25 = 1 1/4; sorry, probably obvious I know)
  • a pinch of salt
  • 3 tablespoons unsalted butter, at room temperature
  • 1/2 cup whole milk
  • 1 egg
  • 1/4 teaspoon pure vanilla extract
These were what the cupcakes looked like when I pulled them out of the oven:

(Canon EOS Rebel XS)
Hm.

To be honest, they didn't look all that different from the unaltered sea-level recipe's results. They even tasted identical -- fine, but a little bit sticky and lacking the signature Hummingbird Bakery crumb. Had I been too conservative in my reduction of baking powder?

I decided my next move would be to reduce MORE baking powder. I reduced the recipe by 3/8ths of a teaspoon this time around:

(Canon EOS Rebel XS)

Still not all that different. It looked like my hypothesis was proving wrong. My next step was to reduce the initial baking powder recipe by half (1/2) a teaspoon -- the same amount that I had reduced the vanilla cupcakes' recipe quantity to, with great success.

This is what the cupcakes with only 1 teaspoon of baking powder (remember the initial amount was 1 1/2 (1.5) teaspoons of baking powder) looked like when I pulled them out of the oven:

(Canon EOS Rebel XS)

OKAY! Still didn't look like that much improvement.

At this point, Erlend pointed out that the cupcakes really did not look all that different from each other. In fact, it looked like there wasn't any differences between them at all.

What on earth was I looking for?!, he asked. According to him, these cupcakes looked fine.

Sure, they looked FINE. But fine isn't what Hummingbird Bakery cupcakes are. The results above, while edible, were NOT the perfect replica of a Hummingbird Bakery cupcake. Hummingbird Bakery cupcakes would have nice, domed cupcake tops that spring back when touched.

These cupcake tops, on the other hand, were either very slightly cratered or flat, with sticky tops that stayed sunken in when touched.

And yes, my friend. That meticulously anal observation is what distinguishes a 1/4 reduction from a 1/2 reduction of baking powder. Slightly-cratered versus flat-topped cupcakes.

So, I rolled up my sleeves and told myself that I would stop after the final reduction. This time, I would reduce the original recipe from 1 1/2 (1.5) teaspoons, to 3/4 (.75) teaspoons. A 3/4 teaspoon reduction, or another way of look at it, a reduction to exactly half of what the original recipe called for.

These were my results:

(Canon EOS Rebel XS)

Okay! That's better.

Do you see that? I was not crazy when I was ranting about flat-tops versus domed-tops before. These cupcakes only contain 3/4 a teaspoon of baking powder. Their tops are domed, as opposed to flat. See the side by side comparison of cupcakes with only a 1/4 reduction (on the left) versus the cupcakes with a 3/4 reduction (right):

(Canon EOS Rebel XS)

There is a difference, however slight. I suppose a non-aerial shot probably would have helped my cause a bit more, but no matter. I'm still getting the hang of my new camera. The cupcakes on the right, with twice as much baking powder reduced, look smoother and less sunken-in. Yes?

So my hypothesis is wrong! At the beginning of this post, I guessed that the chocolate cupcakes would need a smaller reduction in baking powder than the vanilla cupcakes, since the cocoa powder provided more structure and strength to the batter. But this didn't seem to be the case. In the end, I reduced the baking powder for the vanilla cupcakes from 1.5 teaspoons to 1 teaspoon; for the chocolate cupcakes, it was reduced from 1.5 teaspoons to 3/4 teaspoons.

Okay... but why did the chocolate cupcakes need a greater reduction than the vanilla cupcakes?

Hm.

Something to figure out at work tomorrow, I guess.

January 11, 2012

The Science of 'Hey, That's Not So Bad': Chocolate Cupcakes Edition

So the main question that has been plaguing me since my initial control experiment for the Hummingbird chocolate cupcakes is this: why did the unaltered recipe for chocolate cupcakes fare so much better than the unaltered recipe for Hummingbird vanilla cupcakes?

Recall that when I did my initial control experiment for Hummingbird Bakery vanilla cupcakes, I followed the recipe's exact steps and started out by baking the sea-level recipe exactly as it was written in the cookbook. No changes, no alterations. I ended up with 10 muffin spaces filled with sticky puddles of goop:

(iPhone Camera)

Three things caused these puddles of goop to happen:
  1. The outsides of the batter in each individual muffin space rose far too quickly, spilling over the allocated muffin space and the edge of the pan 5 minutes into bake time.

  2. The middles of the cupcakes stayed liquid throughout the entire baking process.

  3. When the cupcakes cooled (or, more specifically, when the weird goopy product cooled), they collapsed into nothing but a pile of liquid goo.
However, none of these things happened with the chocolate cupcakes. This is what happened instead:

(iPhone Camera)

  1. The chocolate cupcakes, while undercooked at the recipe's minimum recommended bake time of 20 minutes, were perfectly cooked at the maximum bake time of 25 minutes.

  2. Although some cupcakes looked a little bloated and rose a teeny bit over their allocated muffin space, the majority stayed where they were supposed to -- that is, there was none of the liquidy, puddle spread that had happened with the vanilla cupcakes.

  3. The chocolate cupcakes cratered and sank a little as they cooled. The tops of the cupcakes were also a little sticky and did not have the nice domed tops that perfectly cooked cupcakes tend to have.

  4. The cupcakes, despite lacking the signature Hummingbird crumb, were actually edible. Pretty decent tasting too.
Well!

I figured I'd start at the same place that I did during my vanilla cupcakes experiment -- that is, take a look at the ingredients list. Here it is for the chocolate cupcakes:
  • 3/4 cup plus 2 tablespoons of all-purpose flour
  • 2 1/2 tablespoons unsweetened cocoa powder
  • a "scant" 3/4 cup sugar
  • 1 1/2 teaspoons baking powder
  • a pinch of salt
  • 3 tablespoons unsalted butter, at room temperature
  • 1/2 cup whole milk
  • 1 egg
  • 1/4 teaspoon pure vanilla extract
Interestingly enough, the ingredients list for the chocolate cupcakes is remarkably similar to the ingredients list for vanilla cupcakes. With the exception of flour and cocoa powder, both recipes call for the exact same ingredients in identical quantities. The only difference is that while the vanilla cupcakes recipe calls for a full cup of flour, the chocolate cupcakes recipe only calls for a 3/4 cup of flour + 2 tablespoons of flour.

The subtracted flour, I assume, is being buttressed by the 2 1/2 tablespoons of cocoa powder. Remember that 1 cup = 16 tablespoons, so the recipe's 3/4 cup + 2 tablespoons = 14 tablespoons of flour + 2 1/2 tablespoons of cocoa powder = 16 1/2 tablespoons of a flour-y, powdery mixture.

Hmm.

Maybe that's why the chocolate cupcakes didn't turn out as goopy as the vanilla cupcakes -- because they've got a half tablespoon more of flour/cocoa powder mixture. Recall that flour adds more strength to batter in general, and ultimately helps prevent the final product from collapsing. For instance, when I added just one additional tablespoon of flour to the original vanilla cupcakes recipe, it was a near miracle -- the cupcakes actually looked like cupcakes! This extra half tablespoon of flour + cocoa powder in the chocolate cupcakes could be my lifesaver.

I also initially suspected that cocoa powder might be a heavier substance than flour. Indeed, my suspicions were confirmed by the Joy of Baking. In their page dedicated to cocoa powder, they write that, "Often times, you may notice that more butter and leavening agent are used in recipes containing cocoa powder. This is to offset cocoa powder's drying and strengthening affect in cakes."

A-ha! I was right.

I was also able to find a more in-depth explanation from a culinary textbook called How Baking Works (This is a recent purchase -- I've been coveting a copy of this book for a while, especially after reading my old roommate's copy in San Francisco. I highly recommend this book for the amateur/serious baker. It's great. Really.). According to author Paula Figoni, cocoa powder absorbs more liquid than an equal weight of flour would. The proteins and carbohydrates in the cocoa absorb liquids from the batter during the process, making the cocoa powder particles heavier -- these heavier particles are not as easily lifted by the leavening agent. So that's why I didn't see the massive puddles of goop like I did in the vanilla cupcakes recipe! Cocoa powder's heavier weight eliminated the excessive rising (and subsequent falling) that tends to occur at higher altitudes!

Epic.

Figoni also goes on to explain that cocoa and chocolate products tend to be powerful structure-builders because most products are over 50 percent fat. The high fat, when baked at the right temperature, gelatinize and ultimately help support the batter's final finished product.

Oh boy! It turns out cocoa powder is my friend after all!

My research above indicates that my first step of action when adapting the chocolate cupcake recipe to high-altitude should be a small one -- it seems that cocoa powder, with its crazy-good absorbing and strengthening power, is doing all the heavy-lifting for me already. I'm going to start out by tinkering with the leavening agent, of course. Maybe a little less baking powder is all I really need. Fingers crossed.

Like I said before, I'm feeling pretty optimistic about this one guys.

December 12, 2011

High-Altitude Hummingbird Bakery Vanilla Cupcakes, Pt. 3: Decreasing Baking Powder

This is the third part of a three-step control group experiment attempting to get the Hummingbird Bakery's vanilla cupcakes recipe to work in the high altitude environment of Denver.

Since I started this oh-so-fruitful experiment, I have long since suspected that baking powder is responsible for the majority of the recipe's failure.

Recall that baking powder is a leavening agent; that is, baking powder is a chemical that produces carbon dioxide in the cupcake batter, causing the batter to rise when baked. Since air pressure lessens at higher altitudes, there is less air pushing down on the cake batter, causing it to rise much more easily. The higher the elevation, the less air resistance, the more easily the baking powder will work.

Now note that Hummingbird Bakery's original recipe calls for an extraordinarily large quantity of baking powder -- 1.5 teaspoons for 12 cupcakes, as a matter of fact. To compare, Thomas Keller's Ad Hoc recipe for white cupcakes calls for 2 teaspoons for 24 cupcakes. That means that the amount of baking powder in a Hummingbird Bakery recipe is nearly as much as the amount of baking powder in a recipe that yields twice as many cupcakes!

Susan Purdy of Pie in the Sky: Successful Baking at High Altitudes recommends subtracting 1/8 - 1/4 a teaspoon for every teaspoon of baking powder in the recipe. I wanted to be conservative, so I heeded her advice and started by taking an 1/8 of a teaspoon away from each of the teaspoons in the Hummingbird Bakery recipe. Which meant I was subtracting a rather awkward amount of 3/8 of a teaspoon of baking powder from the recipe:
  • 1 cup all-purpose flour
  • a "scant" 3/4 cup sugar
  • 1 1/2 teaspoons baking powder minus 3 x 1/8ths a teaspoon of baking powder
  • a pinch of salt
  • 3 tablespoons unsalted butter
  • 1/2 cup whole milk
  • 1 egg
  • 1/4 tspn vanilla extract
I know, I know. It's a really weird, awkward amount. What I ended up doing was first scooping the 1.5 teaspoons of baking powder into a small bowl, and then subtracting 1/8 of a teaspoon from the pile three times. (I recommend using Endurance's Metal Measuring Spoon Set for the task; it's a decently-priced, high-quality set of measuring spoons with a 1/8 tsp piece.)

These are what the cupcakes looked like when I checked them after the recipe's original cook time of 20 minutes:

(iPhone Camera)

Wa-hey! Not bad!

This is the first time I've made cupcakes here that have come out with dome-like tops as opposed to the sunken, cratered centers. This time, there were also no overspilling, save for a couple bloated ones here and there.

I decided that, despite their pleasant shape, the cupcakes still looked undercooked. I decided to leave them in for another five minutes. This is what they looked like after the additional five minutes of baking time:

(iPhone Camera)

Hey! Not bad! Check out these domed-tops:

(iPhone Camera)

Okay, maybe not that domed -- to be fair, they still looked a little flat-topped. But a definite improvement from the cratered centers of my previous attempts. Even the additional flour didn't yield cupcakes this good looking!

Now it was time for the second test -- the cooling process. Most of the sinking and cratering actually happens during the cooling process as warm molecules evaporate, inflating the cake artificially and causing it to sink when it cools. I waited with bated breath for the cupcakes to cool, leaving the room and returning 20 minutes later to find this:

(iPhone Camera)

Wait a second. They don't look THAT much different from when they were warm. Check it:

(iPhone Camera)

Same angle, twenty minutes later. Nearly indistinguishable from the above photo when the cupcakes were still warm.

NICE!

Okay, okay, to be fair, I exaggerated a little bit -- the cupcakes did flatten out a bit as they cooled. The end results were still a little too flat for my liking, but they were at least starting to look like actual, solid, edibles. I think I was a little too conservative with the reduction of baking powder -- next time, I think I'll reduce the baking powder by a full 1/2 teaspoon and see where that takes me.

So how did the cupcakes actually taste?

(iPhone Camera)
Hm.

They tasted... fine. Definitely not Hummingbird flavor -- still way too sticky and moist. A little gummy even. Erlend suggested that the gummy flavor might be a result of being undercooked -- truth be told, the cupcakes do look a little pale (they're supposed to be a golden color as opposed to the pale yellow they are now). I guess this means that I'm going to have to start playing with temperature soon. But not after I keep messing with the baking powder.

All in all, I feel good about this, guys. Things are starting to look good. Finally.

December 11, 2011

High-Altitude Hummingbird Bakery Vanilla Cupcakes, Pt. 2: Decreasing Sugar

This is the second part of a three-step control group experiment attempting to get the Hummingbird Bakery's vanilla cupcakes recipe to work in the high altitude environment of Denver.

Recall that I determined that I could do three things to adjust the recipe:
  1. Add flour, to strengthen the recipe's batter and prevent it from collapsing into a puddle of goop during the cooling process.

  2. Decrease the amount of sugar, since sugar interferes with egg protein's coagulation and requires more heat to set. Alternatively, I could just bake the cupcakes at a higher temperature.

  3. Decrease the amount of baking powder in the recipe, to slow down and decrease the batter's rise.
Last week, I added a tablespoon of flour to the recipe to mixed success. The extra flour strengthened the recipe's batter and contained the cake's rise -- that is, I didn't end up puddles of goop spilling over the pan's edges. However, as the cupcakes cooled, they sank in the center, creating a crater-like appearance.

This week, I decided to decrease the amount of sugar in the recipe. According to the oft-cited Pie in the Sky: Successful Baking at High-Altitudes, the reduction of a little sugar may add sufficient strength and eliminate the need to add additional flour. Sugar has a lot of functions in the baking process, but the most relevant in my case are the following two:
  • Sugar slows down the coagulation of egg proteins.
This means that batter containing a high amount of sugar needs more heat in order to set. The less sugar in a batter, the more quickly the batter will set in the oven.

Note that the unaltered Hummingbird vanilla cupcakes recipe produced puddles of liquidy, sticky goop. That means that the batter never really fully set in the oven. Reducing the sugar could potentially fix this problem.
  • Sugar increases the final product's tenderness.
Sugar interferes with the ability of gluten stands to join together; the more sugar present, the weaker the gluten strands and the more tender the product. Some sugar is therefore necessary to achieve a tender texture. However, recall that liquids evaporate more quickly at high altitudes; such evaporation leaves excess concentrations of sugar in a batter, which can then boil up and easily overflow.

This is especially relevant in my case since a constant issue I seem to have are the cupcakes overflowing from their allotted space and off the sides of the pan. The recipe might be using excess concentrations of sugar, causing this overflow. Decreasing the sugar could potentially stop this.

Without further ado, here is the amended ingredients list (changes are in bold):
  • 1 cup all-purpose flour
  • a "scant" 3/4 cup sugar minus 1 tablespoon of sugar
  • 1 1/2 teaspoons baking powder
  • a pinch of salt
  • 3 tablespoons unsalted butter
  • 1/2 cup whole milk
  • 1 egg
  • 1/4 tspn vanilla extract
This is what the cupcakes looked like when I pulled them out of the oven:

(iPhone Camera)

Dammitwhatthefuck!

I thought that reducing the sugar was supposed to stop the batter from overspreading into puddle-like appearances! Reducing the sugar seems to be a REGRESSION from increasing the flour. At least the cupcakes with the extra flour were kept contained in their little cupcake spaces. These seem more akin to the unaltered Hummingbird Bakery recipe results. ESPECIALLY when they cooled:

(iPhone Camera)

The centers sunk in, creating craters in the cupcakes and completing the "puddle of goop" appearance that I've become so familiar with:

(iPhone Camera)

Getting them out of the pan was another matter entirely. Unsurprisingly, the parts that had overflowed were really stuck onto the metal pan:

(iPhone Camera)

The remaining part of the cupcake -- that is, the batter that actually remained in the allotted cupcake space -- seemed to lack structure entirely. They crushed easily when I tried to pull the cake out of the pan, squeezing together in a weird, moist, sticky mess. The batter appeared to not have set fully. I thought reducing the sugar was supposed to remediate this problem by allowing the batter to set faster with less heat?!

And what about the taste? To be honest, they tasted severely undercooked and bland -- reducing even just a tablespoon of sugar affected the cupcakes' flavor intensely. The final product tasted too flour-y and ultimately, flavorless.

Sigh. Never again will I mess with the cupcake's sugar content.

Well, it's good to know, I guess? It seems that even increasing flour and decreasing sugar still didn't really do a whole lot to contain the over-rising of the original recipe. I have a sneaking suspicion that the final recipe will contain additional flour, the same amount of sugar, and a significantly decreased amount of baking powder. I guess we'll find out in the next post though -- maybe a decrease in baking powder is all I really need.

December 4, 2011

High-Altitude Hummingbird Bakery Vanilla Cupcakes, Pt. 1: Adding More Flour

This is the first part of a three-step control group experiment attempting to get the Hummingbird Bakery's vanilla cupcakes recipe to work in the high altitude environment of Denver.

Once again, sorry for the long silence. Work this week was especially brutal -- I've been spending most days working 7am to 7pm, sitting in on meetings from 8am - 6pm. On the rare occasion I did actually leave work at 5.30, I did some insane working out (think handstand pushups, ring dips; or in my case, extremely modified versions of the excercises) at Crossfit LoDo and came home unable to lift my arms. Doesn't really lend much time for baking experiments. On the plus side, I seem to be featured on my crazy gym's website with increasing regularity, so at least I get some local fame out of this? Snort.

Anyway, so where did I leave off? Pre-Thanksgiving, I did my initial "control" experiment and followed the Hummingbird Bakery's sea-level recipe for vanilla cupcakes to spectacular failure in Denver. The recipe's use of generous amounts of baking powder caused the cupcakes to rise quickly and ultimately collapse into puddles of goop. I determined that I could do three things to adjust the recipe:
  1. Add flour, to strengthen the recipe's batter and prevent it from collapsing into a puddle of goop during the cooling process.

  2. Decrease the amount of sugar, since sugar interferes with egg protein's coagulation and requires more heat to set. Alternatively, I could just bake the cupcakes at a higher temperature.

  3. Decrease the amount of baking powder in the recipe, to slow down and decrease the batter's rise.
Instead of try all alterations at once, I decided to isolate each adjustment so that I could see each change's independent effect on the recipe. This week, I decided to add more flour to the batter.

Susan Purdy of Pie in the Sky: Successful Baking at High-Altitudes advises that, when experimenting, it is best to start with smaller adjustments and work up to larger ones if necessary. I followed this mantra and began by adding just one tablespoon of flour to the original Hummingbird Bakery recipe. The ingredients list that I used is as follows (the steps of the recipe are available here). My amendments to the original recipe are included in bold:
  • 1 cup all-purpose flour + 1 tablespoon of all-purpose flour
  • a "scant" 3/4 cup sugar
  • 1 1/2 teaspoons baking powder
  • a pinch of salt
  • 3 tablespoons unsalted butter
  • 1/2 cup whole milk
  • 1 egg
  • 1/4 tspn vanilla extract
This is what the cupcakes looked like when I pulled them out of the oven:

(iPhone camera)

Not bad! Especially when compared to how they looked the first time I had tried the recipe without any adjustments. The flour seemed to have added the appropriate amount of strength to the cupcake's batter. Sure, they didn't look perfect -- in fact, they looked flat-topped and sunken in. You know how perfectly cooked cupcakes have slightly domed top? Yeah, they definitely didn't have that:

(iPhone camera)

But I was perfectly happy with the results. So, I left the cupcakes to cool as I took a quick walk in the park. Unfortunately, I was definitely too optimistic because when I returned, I was greeted by this:

(iPhone camera)

Oh no! The cupcakes had sunken in even further during my 15 minute walk in the park. They now resembled mini-craters instead of the flat-topped cupcakes I had expected:

(iPhone camera)

Sigh. So they weren't aesthetically pleasing. But how did they taste?

I tentatively pulled a cupcake out of one of the cake slats. It was a good sign that it held together -- the first batch had simply been too goopy (resembling sticky puddles) that had made them impossible to even eat.

(iPhone camera)

Hm. Okay. So the cupcake had actual cake-like texture, which was good. But it was way too sticky. The flavor was pretty decent. Almost a little too sweet, but that might have just been the stickiness contributing to the flavor. All in all, it wasn't bad... just not good. Ha. And of course, nowhere comparable to the actual Hummingbird vanilla cupcake itself.

Sigh. But it's a start, right?

November 14, 2011

The Science of Failure: Vanilla Cupcakes Edition

So, for all you non-believers -- high-altitude really is a game changer when it comes to baking. Recall my "control" experiment from the previous post. A recipe that works beautifully at sea-level yields rather disastrous results at higher-altitudes:


So what went wrong?
  1. The outsides of the batter in each individual cupcake space rose far too quickly, spilling over the edge of the pan 5 minutes into bake time.

  2. The middles of the cupcakes stayed liquid throughout the entire baking process; it appeared that the middle hadn't even cooked! Instead, the oven appeared to have simply "warmed" the batter.

  3. When the cupcakes cooled (or, more specifically, when the weird goopy product cooled), they collapsed into nothing but a pile of liquid goo.
To try and figure out what on earth happened, I decided to go back to the basics and start from the very beginning. I wanted to find out what each individual ingredient's role in the recipe and batter mixture was -- since atmospheric pressure and water's boiling point are lower in Denver, the recipe might be using too much or too little of one thing.

Recall the recipe list for the Hummingbird Bakery's vanilla cupcakes recipe:
  • 1 cup all-purpose flour
  • a "scant" 3/4 cup sugar
  • 1 1/2 teaspoons baking powder
  • a pinch of salt
  • 3 tablespoons unsalted butter
  • 1/2 cup whole milk
  • 1 egg
  • 1/4 tspn vanilla extract
For completely arbitrary reasons, I decided to make my first attempts calibrating the recipe by altering the proportions of the first three ingredients as listed in the cookbook. Let's take a look at the ingredients -- flour, sugar, and baking powder -- in more depth.

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Flour
(recipe quantity: 1 cup, all-purpose)

When used in baking, flour contributes to the body and structure of the final product. It binds the recipe's ingredients together, creating gluten when its proteins blend with liquid. This gluten (a stretchy, elastic substance) then supports and structures the batter.

According to Susan E. Purdy's Pie in the Sky: Successful Baking at High Altitudes, high altitude bakers frequently add extra flour to sea-level formulas in order to add strength to the batter. Adding extra flour increases the amount of gluten in the baked good, which will then prevent the cake from collapsing. Note that the Hummingbird Bakery recipe calls for 1 cup of all-purpose flour; perhaps adding a teeny bit -- maybe one or two tablespoons -- will provide the extra support needed to keep the cupcakes from collapsing in the way that they did? However, the addition of flour is still an incredibly tricky calibration to the recipe -- adding too much flour can toughen the texture of the cake, and we certainly don't want that.


Sugar
(recipe quantity: 3/4 cup)

Unsurprisingly, sugar provides flavor, texture, and sweetness to the final product. It also provides an integral structure to the baked good, as well as serving several practical functions in the baking process.

For instance, almost all recipes call on the baker to cream together sugar and butter. According to the Joy of Baking, the purpose of creaming is to get air into the cake's batter. Sugar granules rub against the fat, producing air bubbles that eventually cause the cake to rise in the oven. Later, these air bubbles enlarge when leaveners like baking soda and powder are added.

Pie in the Sky also warns that sugar attracts moisture, which in turn reduces the amount of gluten formed in the batter. Less gluten produces a lighter batter that will rise more in the oven. However, this lighter batter also means that the baked good has a higher tendency to collapse, especially when it expands too quickly without structural integrity. Too much sugar can therefore be dangerous at high-altitudes, since the sugar has the ability to weaken the batter's structure. Note the high concentration of sugar in the Hummingbird vanilla cupcakes recipe -- no wonder my cupcakes collapsed during the cooling process!

The book also explains that sugar interferes with egg protein's coagulation and needs more heat to set. I have no idea what "egg protein's coagulation" actually means, but I get the gist of it: the more sugar in a batter, the more heat is needed to set the batter. That might explain the weird, wet, undercooked middle of my control batch, especially considering that the cupcakes are baked at the rather low oven temperature of 325 F. It's probably a good idea to increase the temperature of the oven in order to get the cakes to set more quickly.

My boyfriend also suggested that I simply decrease the amount of sugar in the recipe -- you know, considering all the potential problems that sugar can cause at high altitudes. But since I'm such a sugar fiend, I'm not sure I want to do that just yet.


Baking Powder
(recipe quantity: 1.5 teaspoons)

I frequently mention something called a "leavening agent" in this blog. These are chemicals like baking powder and baking soda that produce air, steam, and carbon dioxide gas in batters, causing them to rise when baked. Leavening agents also enlarge bubbles present in the batter from the creaming process, as I mentioned in the previous section about sugar.

The Joy of Baking explains that baking powder consists of baking soda and acidic salts like cream of tartar or sodium aluminum sulfate. These salts react with liquid when it is added to the batter to create carbon dioxide gas. The gas will then cause bubbles in the batter to enlarge. A second reaction also occurs in the oven -- the same gas cells expand and cause the cake batter to rise. Too much baking powder can therefore cause the batter to rise rapidly and then collapse, as air bubbles in the batter grow too large and break.

To add complications to the matter, remember that air pressure lessens at higher altitudes. According to Pie in the Sky, when there is less air pushing down on the batter, it can rise much more easily. The higher the elevation, the less air resistance, and the more easily the baking powder will work. Purdy, author of Pie in the Sky, advises that the amount of leavening in most sea-level recipes must be reduced at higher altitudes to prevent the baked goods from over-rising and collapsing.

The 1.5 teaspoons of baking powder that the Hummingbird recipe calls for seems generous; the American recipes that I tend to favor (this or this, for instance) use smaller amounts of leavening agents in the recipes. I hypothesized in another part of my blog that Hummingbird cupcakes taste differently from American cupcakes because of the bakery's generous use of baking powder. Messing with this step is going to be extraordinarily tricky, especially if I want to maintain the Hummingbird cupcake's unique taste.

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It seems that the Hummingbird Bakery's recipe for vanilla cupcakes are INCREDIBLY dependent on ingredients that cause the batter to rise up, up, and up! While such proportions might work at sea-level, they definitely need to be altered at higher altitudes.

So, after our faux-chemistry/food science lesson, what did we learn?

More flour, more heat, less sugar, and less baking powder = more structure, less rise, less goop.

That should fix all my problems, right?