Baking is often referred to as an “art” rather than an “exact” science. Let me tell you – chemistry is just like cooking. While I typically stick to chemical leaveners (baking soda, baking powder, etc), sometimes more is needed. I’m not talking about more chemicals – I’m talking about a living organism. This particular organism has been around since the dawn of time; humans have used it for everything from making bourbon to baking bread. I’m talking about Saccharomyces cerevisiae, or common Baker’s Yeast.

Baker’s Yeast is of the Kingdom Fungi – rather, yeast is a fungus. You put fungus in your bread and your beer and your cinnamon rolls! It is unlike most other fungi, though. Yeast is a single-celled eukaryote. Moreover, it has the ability to respire via aerobic pathways (produces lots of CO 2 ) or anaerobic pathways (often called fermentation, produces ethyl alcohol, CH 3 CH 2 OH). Humans exploit this to raise our doughs and booze-up our beer/wine/bourbon. Today, we’re going to make cinnamon rolls. Here’s the recipe.

Start by mixing about 7 grams of yeast with about 240 grams warm water. You can buy several types at the store – I prefer the “Active Dry” yeast. It works best to dissolve it in warm water and give it a minute to “wake up” before really using it. Set this in a bowl to the side. On the stove, heat a small saucepan with 38 grams of butter and 120 grams of milk – let this warm up, melt the butter. It is not necessary to scald the butter, though you may. When that’s ready, pour it into your mixer and add 50 grams of sugar, 6 grams of salt, and an egg. Get this nice and mixed and then slowly add about 250 grams of AP flour. The dough should be starting to dry a little, so pour your entire water/yeast mixture in. Mix this in and add the rest of the flour. Depending on your flour’s exact protein content, you might need 200 grams more, you might need 250 grams more. Do it until the dough is not sticky and easily handled.



Remove the dough, roll it into a ball, and throw it into a greased bowl, covered, for almost 4 hours. Every 45 minutes to an hour, punch the dough back down and beat it back into a nice ball. Right now, the yeast is doing its job. I’m not 100% sure which pathway the yeast in your dough uses, but I’d imagine it’s a fair mix of anaerobic/aerobic respiration. In both of these processes, sucrose is broken down into glucose (basic sugar) and fructose (fruit sugar). While the glucose is ready, the fructose has to be broken down once more before it can be processed (see *).

Next comes glycolysis, a process by which the glucose is broken down into energy and waste. The energy keeps the yeast alive and working, the waste is actually CO 2 . The gas gets trapped by the gluten in the flour and the dough rises. You might ask – why do we punch the dough down? We do this so we get nice small bubbles (giving a silky dough feel) vs awful big bubbles (I’ve never tried to get big bubbles, I’ll do an experiment and report later). If we want these small bubbles, and not big bubbles, we have to beat the shit out of the dough to remove the trapped gasses and we have to do it frequently because this is such a long rise. This gives us good flavor, good texture, and hell – it’s kind of fun.

Unrelated, mostly – but there is a video of the aerobic cycle here. It’s done as a rap, it’s educational, and it’s pretty cool.

Once you’re done proofing the dough, use that dirty sauce pan for something tasty. Add 56 grams butter, 150 grams sugar, and 16 grams cinnamon. Heat this mess and mix well, it is easy to burn. If you want other flavors, or if this tastes too sweet, I recommend 4-6 grams of sea salt be added or some ground mace, ground clove, etc. Up to you. This is your filling.

Roll out your dough – I took a baking sheet and rolled the dough until it completely filled the sheet. This recipe works best to make a sheet of 16″ x 9″ x 0.25″. Leaving 1 centimeter around the edges, smear the filling on the dough and then roll it along the long side (hotdog style? Is that a thing?). Using a serrated knife cut the rolls about 2.5 cm thick. Arrange then nicely a greased baking dish – they should touch. That dirty sauce pan? Add a bunch of water and boil it. That baking dish? Put it into a cold oven with that boiling pot of water and let the rolls rise once more – about 45 minutes. Take the pot out of the oven, turn the oven to 175°C (350°F) without preheating for 30 minutes. I used this time to enjoy a nice bourbon and to catch up on my twitter. You can make your glaze.

In your cleaned mixer, cause we did dishes as we went, add 250 grams of powdered sugar, 1 shot of bourbon, 1 tsp vanilla, and 56 grams of melted butter. If your icing looks runny, add more sugar until you can drizzle it. If your icing is too thick, add more bourbon or some water. If you’re like me, just pour the bourbon into a glass and don’t worry about it. When all is said and done, these are some ugly delicious pastries. I ate two – there went my diet.

These don’t travel well, so I won’t be sending any out. Tell you what? You comment on this post and I’ll think about sending my bourbon icing.

Chemistry is all around you – even when we pretend it’s biology (applied chemistry). It’s not good, it’s not bad – it’s just there. Sure, there are some nasty molecules out there, but there are just as many that are super cool. As always, if you have suggestions, comments, questions, let me know.

-N.Tesla

* Correction. I previously stated that fructose had to be “split” into glucose. This is not the case. It is enzymatically converted via an “aldolase reaction” or in the liver (at least, it is in 20-day old rats).