Maillard reaction reviews

From the literature reviewed in Chapter 3, it can be concluded that the Maillard reaction between carbohydrates and proteins is the likely cause of the discoloration of caries lesions. Research in the following chapters focused on this reaction. 

Zhang, Y., Zhang, Y. (2007). Formation and reduction of acrylamide in Maillard reaction A review based on the current state of knowledge. Critical Reviews in Food Science and Nutrition, 47, 521-542. 

Numerous review articles (1-20) and a number of books (21-26) have been devoted to the Maillard reaction, viz., the non-enzymatic browning reactions involving amino acids and reducing sugars. 

The Maillard reaction is inextricably linked to the desirable flavour and colour characteristics of cooked foods and this review provides an insight into some of the chemistry associated with flavour generation in the reaction and the different aromas which are involved. The chemical pathways associated with the initial and intermediate stages of the Maillard reaction are presented and routes by which the important classes of aroma compounds may be formed from Maillard intermediates are discussed. 

Mauron, J. 1981. The Maillard reaction in food A critical review from the nutritional standpoint. Prog. Food Nutr. Sci. 5, 5-35. 

A historical review withl07 references. Life and work of Louis-Cami1le Maillard (Feb. 4, 1878 -May 12, 1936) are described. The first use of the index term Maillard reaction in Chemical Abstracts was in 1950. German scientists with early interest in this reaction were Lintner (1912) and Ruckdeschel (1914). Several aspects of this reaction are reviewed with emphasis on the work of Japanese scientists. 

P. de Lange (3 1 ) of the Central Institute of Food Research (Centr. Inst. Voedingonderzoek), Utrecht, Netherlands reviewed the mechanism of the Maillard reaction, though his title did not show the term. 

Thus, I once considered Thompson (1950) and Patron (1950) to be the first namers of the Maillard reaction. However, Barnes and Kaufman (34) of General Foods Corporation, Hoboken, NJ, published a review in 1947, three years earlier, of which the abstract in CA begins thus "Maillard or browning reaction in foodstuffs is attributed to a reaction between sugars and proteins or other amino bodies," and the review itself repeatedly refers to the Maillard reaction. Later I found that Patron (33 ) cited a paper by Seaver and Kertesz (1946) (35) with this term in the title. 

One of the earlier reviews (31 ) concerned the Maillard reaction in dried milk during storage. Spray-dried whey has considerable amounts of lactose and protein rich in lysine. Theoretical treatment of the problem in whey powder was the object of recent studies by Labuza and Saltmarch (106, 107). 

In their recent comprehensive review of natural and synthetic meat flavors, MacLeod and Seyyedain-Ardebili (20) listed 80 patents describing "reaction products" procedures that produced meat-like flavors upon heating. Approximately one-half of these precursor mixtures included amino acids and reducing sugars. Most of the mixtures described in patented procedures for synthetic meat flavor are modeled after ingredients found in the water-soluble dialy— zable fraction of fresh meat. These constituents serve as reagents for Maillard reactions. 

Maillard reaction products formed by interaction of reducing sugar and amino acids such as a-dicarbonyl compounds, aldehydes, hydrogen sulfide, and ammonia can react further to form derivatives that have been identified from meat or its components during heating. Important reviews of sulfur compounds that might be produced by these reactions have been published by Schutte (35) and... 

Phosphate, ascorbate, NaCl, nitrite, Maillard reaction products, and other antioxidants or prooxidants have been reported to influence development of WOF. Their roles have been reviewed (5), but newer evidence is now available and will be covered herein. 

The studies reviewed demonstrate that browning products produced on retorting of meat inhibit development of WOF, so that canned meat products are not subject to this flavor defect. The flavor of canned meat is less desirable, however, than that of freshly cooked meat. Nevertheless, the strong inhibitory action of the Maillard reaction products against WOF suggests that they could be useful in preventing development of WOF, so further research in this area could be fruitful. 

The first report on antioxidative effect of MRP was made by Franzke and Iwainsky (3). Shortly afterward Griffith and Johnson (4) reported that the addition of glucose to cookie dough resulted in a better stability against oxidative rancidity during storage of the cookies. Research on antioxidative MRP was then mainly performed by groups in Japan. A symposium on Maillard Reactions in Food held in Uddevalla, Sweden, 1979 included also the aspect of antioxidative properties. The contributions on this subject contained also brief reviews (5, 6, 7). Most of the work has been done on model systems. Some applications in food systems have, however, also been reported (8 - 11). 

As a result of the very wide chemical interest which the Maillard reaction has attracted since the early years of this century, and of its diverse commercial and biological implications, a vast amount of work thereon has been published. In this article, the chemical aspects of the reaction between simple amino acids and mono- and di-saccharides will be surveyed the reaction with peptides and proteins will be discussed only when it contributes to our understanding of the mode of interaction between simple amino acids and sugars. The significance of the reaction in the preservation of various foodstuffs has now been reviewed many times2 9 and continues to be the subject of much investigation.10 16 The reaction is also... 

The reaction pathways for the Maillard Reactions have been studied and reviewed by many researchers since Dr. Maillard s early work (4—6) These papers give a concise outline of the major chemical pathways identified in the Maillard Reaction Mechanism. In heat treated meat with nearly 75% of those volatiles generated are pyrazines derivatives (7). Those pyrazines have been found to play an important role in developing a roasted flavor in heated products. They will be discussed later. 

If a nitrogen source is added, or if residual nitrogen-containing compounds are present, classical non-enzymatic browning (MaiHard) along with caramel ization can occur. Although the Maillard reaction is not the major emphasis of this review, it is difficult not to include it in discussions of carbohydrates and their degradation products. 

Pyrazines are the major volatile flavor chemicals produced in Maillard reactions. The discovery of this role of pyrazines was one of the most significant advances in flavor chemistry and two comprehensive reviews of pyrazines have appeared (25, 26). In the 1970 s, pyrazines were well-characterized as the compounds which directly contribute to roasted or smoky flavors. Some pyrazines possess an extremely low odor threshold (25, 29). For example, odor threshold of 2-isobutyl-3-methoxypyrazine in water is 0.002 ppb. 

The importance of Maillard reaction products to the flavor of foods has received considerable attention. One group of Maillard products, the alkylpyrazines, are thought to contribute roasted, toasted and nutty flavor notes to a variety of foods. Several reviews have detailed the presence of pyrazines in a wide variety of foods (1-7). Considerable work has previously focused on mechanisms of formation and the effects of various parameters on pyrazine formation (8-17). Part one of this study reported on the effects of type of amino acid and type of sugar on the kinetics and distribution pattern of pyrazines formed (18). The current study investigates the effect of pH and water activity on the kinetics of alkylpyrazines formation. 

The sensory properties of nearly 450 volatile Maillard reaction products and related compounds have been compiled (45). The review includes quantitative aroma and flavor descriptions, as veil as sensory threshold values for different media, classified according to chemical structure. 

N, S and 0 heterocyclic compounds, along with noncyclic sulfur compounds and hydrocarbons, are predominant in "meaty" flavor volatiles. The mechanisms of heterocyclic formation by Maillard and pyrolysis reactions have been reviewed by Vemin and Parkanyi (57) and the Maillard reaction itself is a recurring subject of review (58). Since other speakers contributing to this volume will discuss these aspects of meat flavor, they will not be repeated in this presentation. 

Heterocyclic compounds are dominant among the aroma compounds produced in the Maillard reaction, and sulfur-containing heterocyclics have been shown to be particularly important in meat-like flavors. In a recent review, MacLeod (6) listed 78 compounds which have been reported in the literature as possessing meaty aromas seven are aliphatic sulfur compounds, the other 71 are heterocyclic of which 65 contain sulfur. The Strecker degradation of cysteine by dicarbonyls is an extremely important route for the formation of many heterocyclic sulfur compounds hydrogen sulfide and mercaptoacetaldehyde are formed by the decarboxylation and deamination of cysteine and provide reactive intermediates for interaction with other Maillard products. 

The purpose of this book is to review aromas that are developed by thermal processes. Because the flavor of heated foods is affected principally by aroma, we focus attention exclusively on the volatile flavor constituents of foods. Moreover, we intend this book to complement the 1986 book. Biogeneration of Aromas, ACS Symposium Series 317, edited by Thomas H. Parliment and Rodney Croteau. A broader overview of the Maillard reaction was discussed in the 1983 book, The Maillard Reaction in Foods and Nutrition, ACS Symposium Series 215, edited by George R. Waller and Milton S. Feather, which addressed the volatile, nonvolatile, and nutritional aspects of the Maillard reaction. 

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