The Flavor of Cinnamon – Spice Science

Adding cinnamon to a sweet sticky roll immediately makes it less sweet. An apple pie with cinnamon is so much richer in flavor. A hint of cinnamon in a stew adds a lot more depth to the dish. The aromatic smell of cinnamon in a drink such as eggnog might make you think of winter. Cinnamon is a powerful and commonly used spice. Even a small amount can change a dish greatly and as you notice, it works in both sweet and savory, food and drink.

But what gives it that strong flavor and smell? And is there really a difference between using a stick vs. the powder form of cinnamon?

Composition of cinnamon

You might be surprised to learn that cinnamon is actually the bark of a tree! It is not a fruit or a seed like a lot of other spices are. Since it is the bark, the composition of cinnamon sticks is actually similar to that of tree stalks and foods such as celery. The majority of a cinnamon stick isn’t flavor, instead, it is mostly made up of carbohydrates (>50%) and fibers (>20%). These molecules are what give the cinnamon bark its structure, ensuring water can move through the plant while it’s living and giving it strength to stand upright.

Cinnamon bark also contains a few percent of fats and proteins and a wide range of vitamins and minerals. Since we eat only so little cinnamon at a time though, the nutritional value of those components is insignificant. Instead, all that we’re after are those flavorsome molecules that make up less than 5% of the whole cinnamon stick!

The cinnamon flavor

The small percentage of the cinnamon stick that actually has that powerful cinnamon flavor is made up of the oils in the stick, also called essential oils. A lot of spices & herbs get their flavor from their essential oils. These essential oils again are a complex mixture of a lot of different molecules, each with its own flavor. In the case of cinnamon, over 80% of the oil is made of cinnamaldehyde (C₉H₈O).

Even though smelling cinnamaldehyde will make you think of cinnamon, it is definitely not alone. Instead, smelling just that one molecule won’t make the flavor complete. A lot of other molecules come in to make up that complex aromatic cinnamon flavor. Other important molecules are eugenol, eugenal acetate, cinnamyl acetate, cinnamyl alcohol, methyl eugenol, benzaldehyde and linalool (and there are lots more).

It is the mixture of all these molecules that gives cinnamon its complex aromatics. It is also why in general artificial flavours have trouble replicating the true complexity of a lot of spices and herbs. Using just cinnamaldehyde, even though it makes up most of the cinnamon, won’t be as complex and rich in flavour and smell!

Fun fact: whereas cinnamon contains a lot of cinnamaldehyde, cumin contains a lot of cuminaldehyde!

It is important to realize that cinnamon is a natural product. As such the composition of the cinnamon differs between harvests, growing areas and plant species. Therefore, it shouldn’t surprise you that a new, different batch of cinnamon that you buy tastes and smells slightly different than another one. Whether you even pick up those differences depends on how often you use your cinnamon. In larger manufacturing facilities though this is something that will have to be controlled more tightly to ensure that cinnamon bun always tastes the same!

Cinnamon types, cassia & ‘true’ cinnamon

Just like a new batch of the same cinnamon type may be different, there are also different types of cinnamon out there. In most general supermarkets you will only find one cinnamon but there are several major types that are sold worldwide. The two main distinctions (as we discussed when discussing the origin of cinnamon) are cassia cinnamon and ‘true’ (it’s official name is actually verum (= true) cinnamon) cinnamon. The cassia cinnamon is what you’ll be used to if you live in western Europe and the US. It work great in baked goods for instance. The ‘true’ cinnamon is a lot milder in flavour and smell and thus works better in more nuanced drinks or savoury dishes.

Antimicrobial properties

It has been found that cinnamaldehyde can actually be used as an antimicrobial substance in some cases. It prevents the growth of a variety of micro organisms. For that reason you will find plenty research looking into the use of cinnamon (oil) for shelf life preservation.

Using cinnamon (sticks)

As we discussed at the start, cinnamon is added to apple pies, cinnamon rolls, plenty of curries and other flavourful savory dishes. Since most of the flavour sits in the essential oils of cinnamon sticks, the flavours in cinnamon are mostly oil soluble. This means that these molecules prefer to sit in fat as opposed to water. If you use cinnamon powder, that is not highly relevant since you’re using the whole sticks.

However, if you’re planning on extracting the flavour from the stick in a sauce or other liquid, it is important that you have some sort of other fat present. This will ensure the molecules will extract into your liquid. Therefore, cinnamon sticks are commonly fried in oil (for a curry spice mix for instance) or soaked in cream.

This process actually is very similar to extraction. Online people have discussed making cinnamon extracts, just like vanilla extracts. Since again the most important flavour molecules are oil soluble extracts are best made with alcohol instead of water. Extraction with water wouldn’t work well since the flavour molecules won’t dissolve.

Cinnamon sticks vs powder

Once cinnamon sticks are broken down into powders the powder will start losing the flavourful volatiles. It seems as if the essential oils in cinnamon we described above disappear pretty easily. So cinnamon powder will slowly lose its flavour (not to say that I don’t have cinnamon powder >1 year old…).

Another difference between the two is the fact that when using cinnamon sticks you discard the sticks and only use the extracted flavour. However, when using powder, you add the entire cinnamon with the milled bark. So your flavour perception will be different. Of course, powder has the great advantage that it can be mixed into a dough or the like a lot easier than a stick which requires steeping etc.

Thickening power of cinnamon?

One of our readers pointed out that when adding cinnamon to coffee or tea it can result in a gel like substance at the bottom. It is not something we’ve seen personally, but when googling the internet it’s apparent that several people have experienced something similar!

In those cases, adding certain types of cinnamon to a hot drink or dish results in a slimy/gel-like substance. Unfortunately, no-one really did any proper research into why this happened. It could be due to the large fibrous molecules in the cinnamon powder, but if you have a better source or explanation, leave a comment behind!

References

• Information on cinnamaldehyde.
• About the origin of cinnamon.
• A Dutch seller of spices.
• The Wikipedia on cinnamon, has some more details on hisotry and origin.

Parthasarathy, V.A., Chempakam, B., Zachariah, T.J., Chemistry of spices, chapter 7, 2008, CABI, link

Peter, K.V., Handbook of herbs and spices, chapter 10 Cinnamon, 2012, Elsevier, link

Wikipedia, Cinnamaldehyde (for the structural formula), link

Read more on the phenomenon of gel like cinnamon in hot dishes:

• Various nice photos of  experimenting with the cinnamon in hot drinks, Today’s apethetic youth
• Cook’s Illustrated discussed the phenomenon as well!
• The phenomenon occurring in a curry, Etherwork
• And another great example of trials done in the kitchen, Walkerssivak