ABSTRACT
Humans have known for thousands of years that heating the food we eat to higher temperatures will improve both its taste and smell. High temperature makes food proteins change structure-coagulate, aggregate, and produce crusts-information that modern food chemists, chefs, and cooks use every day to produce new delicious foods. The French biochemist Louis-Camille Maillard explored and published in 1912 a description of the chemical processes that occur in foods during heating,1 an achievement for which he received the distinguished prize of the French Medical
CONTENTS
7.1 Maillard Products Improve Palatability, But … ........................................... 139 7.2 Heating, Reduction of Antioxidants, and Accumulation of Maillard
Products ........................................................................................................ 140 7.3 Introduction of Molecular Biology Changed the View of AGEs/ALEs ....... 141 7.4 RAGE: A Receptor and Master Switch-A Key Actor in Inammation ..... 142 7.5 Many Players in the Inammation Orchestra ............................................... 143 7.6 Dramatic Alterations in Food Habits ............................................................ 146 7.7 Animal Feeds Have Changed in Parallel with Human Food Changes ........ 147 7.8 Diseases Associated with High Tissue Levels of AGEs/ALEs .................... 148 7.9 Foods Rich in AGEs/ALEs ........................................................................... 149 7.10 Prevention and Treatment of AGE/ALE Accumulation ............................... 150 7.11 Intestinal Flora and Probiotics of Great Importance .................................... 151 7.12 Future Aspects .............................................................................................. 152 References .............................................................................................................. 153
Academy in 1914. The process has ever since been referred to as the Maillard reaction and its products collectively named Maillard products. During the process, socalled reducing sugars —fructose, glucose, glyceraldehyde, lactose, arabinose, and maltose-will bind to amino acids and nucleic acids, both DNA and RNA, peptides, and proteins, and produce compounds usually called Amadori products, which with time undergo complex changes: cyclization, dehydration, oxidation, condensation, cross-linking, and polymerization to form irreversible chemical products. In particular, reactive carbonyls, such as glyoxal and methylglyoxal, have been found to rapidly modify reactive side chains of proteins. Important amino acids, such as lysine (essential amino acid) and histidine (essential for children), are often involved. During the heating process, thousands of good-tasting and good-smelling volatile compounds are released in addition to signicant amounts of pigments (melanoids) that often make the food or parts of the food brown or black, which is why sometimes the process is referred to as “browning.” Common browning products are bread crusts and the roasted surface of fried meat and sh. All sorts of broths, irrespective of vegetable or animal origin, Chinese soy, Balsamico products, smoked foods are rich in brown/black Maillard products. But not all Maillard products are dark in color. White Maillard products also exist; common examples are diary products, especially cheese and powdered milk. It was suggested early on that the Maillard process might be negative to health, at least when its products are consumed in larger amounts, as these products will accumulate in the body, sometimes for the rest of life, but also because the process might reduce the supply of important and essential amino acids to the body.
