March 14, 2013

The Chemistry of Snack Food: Why Are Those Chips So Tasty?

by Gina Battaglia

You sit down to your favorite TV show with a large bag of cheese puffs. Losing yourself in the exciting plot, you start snacking away. You are not quite sure whether it is the salty, slightly tangy cheesy flavor, the crunchy, melt-in-your-mouth texture, or the visually appealing bright orange color, but by the first commercial break, you have eaten half the bag.

Many of us find it difficult to stop at “just one” chip, cookie, or cracker. According to a recent article published in the New York Times, it may be more than a lack of willpower on your part. Food companies employ flavor chemists who optimize the taste, texture, and color to create a seemingly irresistible snack. Although making a tasty, perhaps slightly addictive snack makes for better sales, many health experts blame the heavy reliance on processed food over the past few decades for the rising rates of obesity and associated diseases such as type 2 diabetes and hypertension.

The foundation of food science was established in 1912 when French chemist Louis-Camille Maillard discovered that gently heating sugars with amino acids produced a yellow-brown color and an aromatic scent. The military became interested in producing mass amounts of nonperishable, flavorful food for its soldiers during World War II, sparking renewed interest in the details of this chemical reaction. In 1953, African-American chemist John E. Hodge published the three-step reaction mechanism for the reaction Maillard previously identified, later named the Maillard-Hodge reaction. The products of this biochemical reaction, often called Maillard reaction products (MRPs), produce the pleasurable flavors and odors we associate with cooked food. Altering factors such as temperature, types of sugars and amino acids used, moisture, pH, and chemical composition in the food affects the characteristics of the end product–whether it has a dark brown or grayish hue, smells like rye bread or meat, or has a gelatinous or creamy consistency.

Manipulating MRPs is a delicate science and is the central focus of multi-billion dollar food companies, such as Coca Cola, Nestlé, and Frito-Lay. These companies employ hundreds of food chemists to manipulate the color, texture, flavor, and aroma of their food products. A typical lab uses around 2,000 chemicals and 500 natural flavors, and some products require over 100 tries to get just the right combination. Simply starting with the wrong sugar or heating the mixture too quickly could be the difference between beautiful, golden-brown chocolate chip cookies or cookies with a dull, brown color. The optimal combination of these chemicals also create a satisfying, melt-in-your-mouth texture that, in the case of your airy cheese puffs, makes you feel like each piece is practically calorie-free. Along with the extensive, secretive testing involved in creating the perfect chemical blends, the addictive factor is pumped up with the addition of salt, sugar, and fat to these processed foods.

Recently, some research has suggested that consuming certain MRPs, such as acrylamide and 5-hydroxymethylfurfural (HMF), could decrease nutrient absorption and increase risk of developing Alzheimer’s disease, cancer, and other diseases. Furthermore, the pleasurable tastes and textures of these often calorie-dense foods also makes it easy for consumers to overeat, possibly magnifying the chemical load on our bodies and contributing to the current obesity epidemic in the United States. Food scientists have been experimenting with methods for neutralizing the potentially harmful reaction products. A notable one in the developmental stages involves using the enzyme asparaginase in the preprocessing step to reduce the amount of acrylamide produced in the final food product. However, battling the urge to overeat may be the bigger challenge, especially since the goal of the food companies is to get consumers “hooked” on their product. Therefore, developing methods of reducing production of harmful MRPs, as well as moderating our consumption of processed food, will help produce safer foods and improve our health.

Learn more:

Read the full New York Times article: The Extraordinary Science of Addictive Junk Food

Read about the history and science behind the Maillard Reaction

Read about How Flavor Chemists Make Your Food So Addictively Good

Gina Battaglia

Written by

Gina has been writing and editing scientific content since 2006. She has been published in the American Journal of Physiology-Endocrinology and Metabolism and the Journal of Strength and Conditioning Research, and assisted with editing duties for the International Journal of Sports Medicine for four years. She holds a Ph.D in Bioenergetics from East Carolina University, a field that integrates exercise physiology, basic physiology, and biochemistry. Gina helps write blog content and develop learning modules for Visionlearning.

The views expressed above do not necessarily represent those of Visionlearning or our funding agencies.