Cultivation of a Cheesemonger

A Blog of Cheese Culture and Cultures

“Flowery,” “Steamed Broccoli,” “Dank Basement,” – Where do Cheese Flavors Come From?

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Alternative title: Fat is Flavor!

Screen shot 2013-01-10 at 1.28.42 PMOne of the key flavor formation pathways is the enzematic hydrolysis (lipolysis) of triglycerides.  Okay, let’s break that statement down into it’s basic parts:  A triglyceride is a molecule that is composed of a glycerol with three fatty acids.  Enzematic hydrolysis, or lipolysis, is the breakdown of lipids – of which, triglyceride is one – that cleaves the bonds between the glycerol and its fatty acids.   Since this is enzematic hydrolysis, the enzymes lipase and esterase are catalysts that help speed up this reaction.  So, through the speedy separation of glycerol and fatty acids aided by lipase and esterase, the fatty acids are removed from the triglyceride and it is these fatty acids that cause the various flavors we perceive in cheese.  Once these fatty acids are removed from the glycerol, they are called free fatty acids.

Recap:

Lipolysis = Triglycerides (glycerol + 3 fatty acids) + lipase/esterase enzyme = free fatty acids = TASTY GOODNESS!!

Cool!  But there are so many flavors in cheese – how do free fatty acids create them all?

A fatty acid is made up of a carboxyl group and, more importantly for our purposes, a hydrocarbon ‘tail’.  Free fatty acids found in cheese have short-chain hydrocarbon tails that consist mainly of 4, 6, 8, or 10 carbons.  Short-chain fatty acids provide desireable piquant flavor and aroma in many cheeses.  The fat in sheep’s milk and goat’s milk contains higher concentrations of short-chain fatty acids than that in cow’s milk. Because of this, some sheep and goat cheeses attain a more peppery, piquant flavor and aroma profile than their cow’s-milk counterparts.

Further reactions of the fatty acids (such as oxidation) cause various specific flavors produced by different fatty acid flavor derivatives: ethyl esters (fruity aromatic notes, floral, goaty), thioesters (cheesy, cooked vegetable), branched chain keto acids (pungent cheesy), and unsaturated alcohols and ketones (mushroom-like). N-Methyl ketones, prduced by partial beta-oxidation of fatty acids, are of particular importance to blue cheese flavor.

An experiment published in The Journal of Dairy Science analyzed the flavors of various cheeses and the number and type of free fatty acids found in each one.  The results are quite interesting:

Port  Salut  and Monterey  Jack  are  two  semisoft  cheeses with similar flavor  characteristics – they are mild  and  milky although the Monterey Jack  cheese  had  a  slightly  more  sharp, diacetyl-like flavor.  Interesting to note is that their flavor characteristics are similar and their free fatty acid profiles were also similar.  And, of the cheese varieties analyzed, these two cheeses were among the lowest concentrations of free fatty acids.

Limburger cheese, known for it’s strong taste and stronger smell, contained some of the largest amounts of 4 and 6 chain carbon free fatty acids among the soft and semisoft cheeses.  Gruyere also contained relatively high concentrations of  4 and 6 chain free fatty acids.

Gjetost  and  goat’s  milk  cheeses both contained  goat’s  milk  fat,  but  the caramelized  Gjetost  exhibited  only  a  mild goaty  flavor.  The  Gjetost  probably  contained some  cow’s  milk,  whereas the  goat’s  milk cheese  was  manufactured  with  only  goat’s milk,  which  accounted for its higher  concentrations of 8 and 10 chain free fatty acids and  stronger  goaty flavor.

carbon chain lengths of different cheeses

Why is the Camembert originating from Germany? I don’t know.

Look at how many more 4, 14, and 16 carbon chain free fatty acids brie has compared to camembert! On the other hand, the French Roquefort and the U.S. blue are awfully similar in the total amount of free fatty acids.

Of course, terroir and breed of animal affects the flavor as well, perhaps introducing a different concentration of free fatty acids into the cheese, but that is a topic for next time.

 

References

(1) Jelen, Henryk. Food Flavors: Chemical, Sensory and Technological Properties. CRC Press, 2012

(2) Kindsedt, Paul, Vermont Cheese Council. American Farmstead Cheese: The Complete Guide To Making and Selling Artisan Cheeses. Chelsea Green Publishing Co., 2005

(3) Woo, A.H., Kollodge, S., Lindsay, R.C., Quantification of Major Free Fatty Acids in Several Cheese Varieties. Department of Food Science, University of Wisconsin-Madison, 22 February 1983 http://download.journals.elsevierhealth.com/pdfs/journals/0022-0302/PIIS0022030284813806.pdf

Journal of Dairy Science Volume 67, Issue 4 , Pages 874-878, April 1984

(4) Friberg, Stig., Hui, Yiu H., Handbook of Food and Beverage Fermentation Technology. Taylor & Francis e-library, 2005

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One thought on ““Flowery,” “Steamed Broccoli,” “Dank Basement,” – Where do Cheese Flavors Come From?

  1. Mia, I am learning so much from your blog. I just wish I had the cheese here now to taste as you discuss it.

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