Maillard Reaction and Why Foods Brown

Maillard Reaction and Why Foods Brown The Maillard reaction is the name given to the set of chemical reactions between amino acids and reducing sugars that causes browning of foods, such as meats, breads, cookies, and beer. The reaction is also used in sunless tanning formulas.  Like caramelization, the Maillard reaction produces browning without any enzymes, making it a type of non-enzymatic reaction. While caramelization relies solely on heating carbohydrates, heat is not necessarily needed for the Maillard reaction to occur and proteins or amino acids must be present. Many foods brown due to a combination of caramelization and the Maillard reaction. For example, when you toast a marshmallow, the sugar carmelizes, but it also reacts with the gelatin through the Maillard reaction. In other foods, enzymatic browning further complicates the chemistry. Although people have known how to brown food pretty much since the discovery of fire, the process was not given a name until 1912, when  French chemist Louis-Camille Maillard described the reaction. Chemistry of the Maillard Reaction The specific chemical reactions that cause food to brown depend on the chemical composition of the food and a host of other factors, including temperature, acidity, the presence or absence of oxygen, the amount of water, and the time allowed for the reaction. Many reactions are occurring, making new products that themselves begin reacting. Hundreds of different molecules are produced, changing the color, texture, flavor, and aroma of food. In general, the Maillard reaction follows these steps: The carbonyl group of a sugar reacts with the amino group of an amino acid. This reaction yields N-substituted glycosylamine and water.The unstable glycosylamine forms ketosamines through the  Amadori rearrangement. The Amadori rearrangement signals the start of the reactions that cause browning.The ketosamine may react to form reductones and water. Brown nitrogenous polymers and melanoidins may be produced. Other products, such as diacetyl or pyruvaldehyde may form. Although the Maillard reaction occurs at room temperature, heat at  140 to 165  Ã‚ °C (284 to 329  Ã‚ °F) aids the reaction. The initial reaction between the sugar and the amino acid is favored under alkaline conditions.

State Unit Study of California

State Unit Study of California These state unit studies are designed to help children learn the geography of the United States and learn factual information about every state. These studies are great for children in the public and private education system as well as homeschooled children. Print the United States Map and color each state as you study it. Keep map at the front of your notebook for use with each state. Print the State Information Sheet and fill in the information as you find it. Print the California State Map and fill in the state capital, large cities and state attractions that you find. Answer the following questions on lined paper in complete sentences. State Capital What is the capital?State Flag Who designed the flag?State Flower Where did the scientific name come from?State Bird How is this bird easily recognized?State Tree What is the average trunk diameter?State Song Who wrote the state song?State Seal What river is the miner working by? Heres a great picture of the state seal.State Animal How tall do these animals grow?State Marine Mammal How big do these whales grow?State Reptile What are the eating habits of this reptile?State Fish When did this fish become the official fish?State InsectWhat is the wingspan of this insect?State MineralWhat is the foundation of the economic history of California?State RockWhat is the coloring of this rock?State Motto What does this Greek word mean? California Printable Pages - Learn more about California with these printable worksheets and coloring pages. California Word Search - Find the California state symbols and other related words. Did You Know... List two interesting facts. California Landmarks - The state of California has designated nearly 1100 sites as California State Historical Landmarks. This site has pictures of many of them. Your Idea Becomes a Law - Learn how a bill becomes law in the State of California. San Diego Natural History Museum - Explore the activities at the Kids Habitat. Energy Quest - Energy education from the California Energy Commission. Big Orange Online - Learn about the California orange industry and create your own label. The California Gold Rush - Learn all about the California Gold Rush with this online student booklet. Odd California Law: It used to be illegal to peel an orange in a hotel room.