Pancakes Tuesday is upon us again. In my house the pancake is not so much an annual event, but a weekly one and with that kind of frequency we have covered a lot of questions about this delicious food.
So, if like me, you have ever wondered about the history of the pancake, the science of getting them just right, why they are round or even the formula for the perfect pancake flip (L = 4 H /P- D / 2 if you’re interested) then read on!
The first pancake
Before we delve into the science behind the perfect pancake, here is a bit of history. The pancake as we know it seems to be the mastermind of the ancient Greeks. In the 6th century they started combining ground wheat with olive oil, honey and milk – and so the first pancake was born. If we expand our basic ideas on what a pancake really is we could look back further still to the process of making flat bread from ground grains and nuts mixed with milk or water, dating back to the Neolithic period.
The more modern variety
If we start within Europe a modern pancake can be classified as the round flat variety similar to the French crepe; it contains some form of flour and a liquid such as milk or water. These flat pancakes usually also contain eggs and butter, and sugar in the sweetened variety. Then we also have the thicker, fluffier pancakes that contain a raising agent; the name and variation of these include Scottish pancakes, drop scones and of course the well know buttermilk pancakes – an American staple.
What goes into a pancake?
If we take a closer look at the primary ingredients we begin to see the complexity and science that really goes into making the perfect pancake:
FLOUR… the backbone of the pancake as it provides structure
SUGAR….as well as adding to the pancakes taste and colour, sugar also keeps the pancake from getting too thick and stodgy
EGGS…. the proteins in the eggs add to the structure of the pancake and to the overall flavour
BUTTER/FAT… as with the sugar, the fats keep the pancake tender and prevent them from becoming overly stodgy
MILK/WATER… the liquid portion of the pancake also adds to the structure and is necessary for certain chemical reactions to occur
RAISING AGENT… as the name suggests, these agents help raise the pancake, making them light and fluffy
You can of course find many varieties with their own local changes and substitutes, one example being potatoes which are commonly used in place of flour, as the starch ingredient.
Flat pancakes and crepes
These types of pancakes usually contain flour, milk and sugar. From the above list we can now predict that the flour is the body of the pancake, it provides the structure, but how does it do this?
There are two proteins found in flour called glutenin and gliadin. Once moisture is added to flour (in this case milk) these two proteins link together to form gluten. Gluten is a “sticky” protein; its stickiness allows it to form a network, adding structure to the batter.
Then there is the sugar, which caramelizes on heating, adding sweetness to the mix and contributing to the colour of the pancake as it cooks. The sugar also prevents the pancakes becoming too thick and stodgy by reducing the amount of gluten produced.
Buttermilk or American style pancakes
What about the thicker pancakes? The main difference between these and their thinner cousins is that they contain a raising agent! Yeast is a biological raising agent used in some baking, it produces carbon dioxide gas while digesting sugar and this gas forms tiny bubbles within the mixture. When heat is added during baking these bubbles expand making the bread/cake “rise”.
The main drawback with baking with yeast is that it requires time and who really wants to wait too long for their breakfast? That is why, when using raising agents in pancake mixtures, we substitute the yeast for bread soda and/or baking powder; but what exactly is the difference between these two?
Bread soda versus Baking powder
Bread soda (also referred to as baking soda) is pure sodium bicarbonate. Baking powder actually contains bread soda but it also contains a powdered acid (usually cream of tartar – potassium bitartrate).
Bread soda (sodium bicarbonate) is an alkali/base and will react with an acid (such as the buttermilk used in pancake batter) producing salt, water and carbon dioxide gas…
BREAD SODA + ACID —–> SALT + H20 + CO2
This carbon dioxide gas gets trapped in thousands of tiny bubbles within the gluten making the batter rise on cooking, forming light and fluffy pancakes (the same process as with the yeast but a lot quicker).
The baking powder has the added advantage of having the acid already present, so once a liquid is added the dry acid and alkali can react in the same way.
So now that we are starting to understand the science of it all how do we use this knowledge to make the best pancakes?
The science of flavour
The Maillard reaction describes a series of chemical reaction between certain amino acids and sugars that create the odours and flavours of food.
Heat is also necessary for these reactions to occur. The Maillard reaction describes the science of flavour.
MAILLARD REACTION: Amino Acids + sugar + heat -> flavour and odour
What exactly does this have to do with our pancakes? Well, Maillard reactions work best in alkali conditions so bread soda is a definite plus is making golden tasty treats. However, if we add too much bread soda the pancake will brown too quickly and will have an acrid burnt flavour; not to mention the unpleasant taste produced from the left over bread soda. It is trickier than you might imagine but luckily someone has already done the science bit for us and worked out the ideal amount of bread soda required.
A little lumpy is OK
We are all used to mixing things thoroughly when baking but that is not always the best way to do it. When it comes to making the best fluffy pancakes, a batter that is a little lumpy is much more ideal. If we over mix we form too many bonds between the gluten molecules and this tight network makes for some pretty flat pancakes.
Time to speed it up
You will be glad to hear that speed is recommended when preparing pancakes; when making buttermilk pancakes we do not want all the bubbles we have created to be lost. Although it is good to allow the batter sit for a few minutes to allow the gluten to “relax” (build up a sufficient network) if left too long the bubbles will burst and the resulting pancakes will be flat and dense.
Why are pancakes round?
Pancakes are round for two main reasons, gravity and surface tension. Once the pancake pan is flat gravity will pull on all parts of the batter uniformly in all directions, pulling it out into a round shape. Add to this surface tension which pulls evenly on the edges, maintaining the round shape as it cooks.
The science of pancake flipping
Would you believe that someone has actually looked into the exact science of flipping a pancake ? I love to see scientists take their pancakes seriously!
According to Professor of Mathematics, Frank Smith, from the University college of London, the simple mathematical formula for the perfect flip is: L = 4H/P – D/2
(L = hand distance from inner edge of the pancake / H = height of flip / D = diameter of pancake)
Or maybe you are more into the speed of it? Not to worry, that has been covered too.
Dr. Tungate, a senior physics lecturer at Birmingham University, found that…
“A pancake should be flipped into the air at a speed of 10 miles-an-hour, which means that it takes less than 0.5 of a second to reach the top of its trajectory.”
The only bit that remains is the science of what you actually put on your pancakes and that’s when I hand it over to you! Whatever toppings you choose, I hope you have a great pancake celebrating day!