FALCONIUM

    Cooking is a pastime for many, but what is supposed to be a new, exciting experience often ends in disaster. But have no fear--what once required a perfected-through-generations approach can now be explained by chemistry. Basting the perfectly browned duck and keeping your bushel of bananas the perfect shade of banana yellow are both linked to chemistry. The magic of that secret family recipe all lies in science because, really, cooking is chemistry.

    Perfectly cooked asparagus hides its secrets in its chemical makeup: it has tiny air cells on its surface. As retired biochemist Shirley Corriher observes, "If we plunge [asparagus] into boiling water, we pop these cells, and they suddenly become much brighter green.” But when asparagus is overcooked, the cells shrivel and their cell walls break down into pectin, a polysaccharide that dissolves in water. Acid begins to leak out of the cell walls, raising the acidity of the boiling water and increasing the concentration of positive hydrogen (H+) ions in the asparagus. The change in ion concentration causes the alkaline vegetable, originally composed of mainly hydroxyl (OH) ions, to become more acidic, coloring the vegetable a dull, unappetizing gray. Although changes in acidity and alkalinity are major concepts of kitchen chemistry, cooking science is not limited to just that.

    The beauty of a perfect fruit bowl can freshen up a home, but an overripe speckled banana always sticks out. How is it possible that a green banana can become overripe overnight? The culprit is ethylene gas, which is mainly emitted by bananas and apples. When bananas are exposed to ethylene, starches are broken down into flavorful sugars by the alpha-amylase enzyme, speeding up the ripening process to an unappealing degree. Yet some have already taken advantage of this chemical phenomenon. For example, before putting produce on the shelves, many supermarkets “gas-blast” their vegetables with ethylene to induce faster ripening and enhance the flavor of their produce.

    How does sugar also play a role in the browning of meat? Fondly referred to as the Asian turkey, the duck is a common centerpiece on the Asian table. The secret behind that perfectly basted bird is the use of seasonings high in fructose or glucose, such as honey. The honey not only adds sweetness; it also contains “reducing sugars” which contain carbonyl (CHO) groups, compounds that aid in the Maillard reaction. The Maillard reaction is a chemical reaction between the heated, denatured proteins and the sugars on the surface of the poultry. This reaction creates a browning effect, giving meat a distinct, meaty flavor as well as a pleasant brown color.

    The process of baking and making dough has a chemical explanation as well. Gluten is key to creating a perfectly flaky pie crust or mouthwatering homemade biscuits. Gluten is a type of protein in flour that supports the bread, and is activated when water is added to the flour. Kneading dough helps establish a “gluten network” throughout the dough, forming sturdier material for breads. However, the delicate dough for pastries needs to have a lighter, fluffier texture, so flour with lower protein content is often used when baking pastries and cakes. To add airiness to the bread or pastry, a leavening agent, such as baking powder, baking soda, or yeast, is also used. These agents all aerate the dough during baking by forming carbon dioxide bubbles within the bread or pastry. However, if too much leavening is used, the baked good will fail to rise due to excessive carbon dioxide formation that causes the air bubbles to all rise to the top.

    Chemistry lies in all aspects of cooking and is widely acknowledged by the best chefs. While many look toward the “practice makes perfect” maxim for culinary guidance, one can become a skillec cook more rapidly with the knowledge and application of chemistry. The application of chemistry to cooking is an innovative approach to improving one’s culinary expertise, and an effective one at that. Even if this newfound chemical knowledge won’t make you an instant five star chef, it is still true: science tastes good.

By Connie Liu

"Better Cooking Through Chemistry // The Fighting 44s." The Fighting 44s // Asian American Issues, Politics, Social Dynamics, Art & Literature. Web. 23 June 2010. .

"Chemistry Of Cooking -- A Biochemist Explains The Chemistry Of Cooking." Science Daily: News & Articles in Science, Health, Environment & Technology. Web. 23 June 2010. .

"Ethylene Gas - Ripening Fruit & Cut Flowers." The Produce Blog. Web. 23 June 2010. .

"Science of Meat: What Gives Meat Its Flavor?" Exploratorium: the Museum of Science, Art and Human Perception. Web. 23 June 2010. .

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