The Chemistry of Macarons

Introduction

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A macaron is a sweet meringue-based confection made with egg white, icing sugar, granulated sugar, almond powder or ground almond, and food coloring. The macaron is commonly filled with ganache, buttercream or jam filling sandwiched between two cookies. The name is derived from the Italian word macarone, maccarone or maccherone, the meringue.  I chose this topic because I love macarons and think they are a delicious treat.  I also wanted to get to know what reactions occur to produce them.  My life has been affected by macarons because I like to bake and these cookies are a lot of fun to make.

Composition of ...

  • Egg Whites

    • C6H8N2O4

  • Icing Sugar

    • C12H22O11

  • Granulated Sugar

    • C12H22O11

  • Ground Almond

    • C7H6O

  • Food coloring

      • C18H14N2Na2O8S2
Main Chemicals, Compounds, Components

Egg whites: (C6H8N2O4) Egg whites are a type of protein.  The egg white proteins form enough bonds to make meringue peaks.  The meringue adds volume to the macaron shells.

 

Sugars: (C12H22O11) Sugar is sucrose.  The sugar is combined with the egg whites to produce the meringue; which gives the macarons their volume.

Chemistry's Role

A critical step in macaron making is the beating of egg whites to form a medium-stiff meringue. A meringue is described as an “egg white foam”: upon beating, egg white proteins unfold and join together to form a “reinforcing network” consisting of “bonds between positively and negatively charged parts of molecules, between water-like parts, between fat-like parts, and between sulfur groups.  A medium-stiff meringue forms soft yet sturdy peaks.  Structurally, this is the point at which egg white proteins have formed just enough bonds with each other to form loose “cages” around water droplets present in the mixture, creating a stable matrix of water droplets held within a protein structure.

Overall, a high granulated sugar recipe produced a stiffer meringue that, when mixed with the dry ingredients, yielded a sturdier batter and subsequently a stronger macaron. However, it suffered from impaired rise in the oven, possibly due to the effects of increased viscosity and stiffness of the protein network upon addition of more granulated sugar to the meringue.  By contrast, a high powdered sugar recipe produced more rise, yielding a taller and more symmetrical foot that was more aesthetically pleasing. However, the overall texture of these macarons was compromised by the large air pocket that formed with baking, possibly due to the weaker meringue.

Background Research

A macaron is made by combining icing sugar and ground almonds until fine. In a separate bowl, egg whites that are beaten until a meringue-like texture.  The two elements are then folded together until they are the consistency of "shaving foam", and then are piped, left to form a skin, and baked.  Sometimes, a filling is added.  So not exactly technical terms, but it's all about the chemistry of the egg white proteins, the ratio of ingredients working together, the drying-out of the shells and the oven temperature, and the physics of proper air distribution.

Resources

(background information)

https://www.quora.com/What-is-the-science-behind-making-macarons

(chemical reactions needed)

http://www.cookingscienceguy.com/pages/wp-content/uploads/2012/07/Food-Science-

acaron3.pdf

(chemistry’s role)

http://loveandmacarons.blogspot.com/2013/04/french-meringue-method-vs-italian.html

(background information)

http://bobbiesbakingblog.com/blog/2012/04/29/french-macaron-terms/  

(components)

http://www.lookchem.com/Egg-white/

(egg white chemical formula)


About the Author
Madison Hansen is a junior at Billings Senior High School.  She is enrolled in orchestra and a number of honors classes.  Outside of school she enjoys reading, drawing and hanging out with her little sisters.  She wishes to attend MSU Bozeman and major in art education.







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