Maillard maltol

The formation of oxygen-containing heterocyclic compounds is also a consequence of the Maillard reaction. Amines and amino acids have a catalytic effect upon the formation of 2-furaldehyde (5), 5-(hydroxy-methyl)-2-furaldehyde (11),2-(2-hydroxyacetyl)furan (44),2 and 4-hy-droxy-5-methyl-3(2//)-furanone (111) (see Ref. 214). This catalytic effect can be observed with several other non-nitrogenous products, including maltol. The amino acid or amine catalysis has been attributed to the transient formation of enamines or immonium ions, or the 1,2-2,3 eno-lization of carbohydrates. Of interest is the detection of A -(2-furoyl-... 

Hydroxy-2-methyl-4//-pyran-4-one (maltol) and 2-acetyl-3-hydroxy-furan (isomaltol) are also products of the Maillard reaction. Both have a considerable history, due to their early detection in beer and breads. A mechanism based upon the pyranose form of a methyl-a-dicarbonyl inter-... 

Furans are the most abundant products of the Maillard reaction and they account for the caramel-like odor of heated carbohydrates (8). Some sugar degradation compounds, such as maltol, isomaltol, 4-hydroxy-5-methyl-3(2H)-furanone, 2,5-dimethyl-4-hydroxy-3(2H)-furanone, and 2-hydroxy-3-methyl-2-cyclopentene-l-one (cyclotene), have odors usually described predominantly... 

Heating also produces a series of other substances as a result of Maillard reactions. These include cyclotene, maltol and its derivatives (hydroxymaltol, dihydro-maltol), 2,3-dihydro-5-hydroxy-2-methyl4(/7) pyranone (DHM) and its 5-hydroxy derivative (DDMP) and furaneol. The sensory impact of these components can play an important role in developing the toasted , burnt , or caramel aromas of some barrel-aged wines (Cutzach et al. 1997,1999). 

Furaneol is formed when the sugar rhamnose is heated in the presence of a substance containing an amino group through a Maillard reaction (Fig. 3.62). HMF results from heating of fructose (Fig. 3.63). Both furanones occur in various foods. For example, Furaneol has been identified in pineapple, strawberries and popcorn both Furaneol and HMF have been found in meat broth [21 [. Both furanones are applied as flavour modifiers in foods where maltol and ethyl maltol are used [1[. 

Heat transforms ketoacids to methylketones like 2-heptanone, 2-nonanone with a green fatty metallic blue cheese note. Hydroxyy acids form the corresponding lactones. The creamy, buttery, coconut-like 5-decanolide, 4-dodecanolide, 5-dodecano-lide contribute to the sweet creamy buttery flavour in cream and butter. Lactose undergoes a caramelisation reaction to develop sweet, caramelic maltol and 4-hy-droxy-2,5-dimethyl-furan-3(2H)-one. Lactose and milk proteins react in a Maillard reaction to roasted, nutty, burnt notes such as 2,5-dimethyl pyrazine. 

In addition to Maillard reactions, caramelization reactions, involving the dehydration and decomposition of sugars, can form a variety of volatile compounds found in roasted tree nuts such as heterocyclic oxygen-containing furan derivatives and maltol. 

Cocoa flavor. Some of the over 500 known volatile components of C. f. are already present in raw cocoa, but most are formed after diying and roasting (at 110-130 °C), mainly by Maillard or Strecker reactions from amino acids, peptides, and sugars resulting from anaerobic fermentation. C. f. is not determined by one impact compound but is rather a composition of various aromas caramel-like ( maltol, Furaneol , and 2-hydroxy-3-methy 1-2-cyclopenten-1 -one), flowery ( linalool, 2-phenylethanol, phenylacetaldehyde). 

Volatile components formed from the reaction of monosaccharides or disaccharides with P-alanine were investigated in a dry condition as a model system of cookie processing. Maltol is a common compound formed in the Maillard reaction, but it was very difficult to detect it in previous experiments using actual cookie materials. In this work, we investigated the principal compounds and maltol formation from the reaction of monosaccharides or disaccharides with P-alanine at 150 °C for 10 min. Neither the reaction of monosaccharides nor the disaccharides with P-alanine resulted in the formation of maltol. 2,3-Dihydro-3,5-dihydroxy-6-methyl-4(H)-pyran-4-one (DDMP) was detected as a principal product from the reaction of monosaccharides with P-alanine. 5-Hydroxymethyl-2-furfural was also confirmed as being a major product in both reactions. 

Yaylayan, V.A. Mandeville, S. Stereochemical control of maltol formation in Maillard reaction. J. Agric. Food Chem. 1994, 42, 771-775. 

Raw or gently pasteurised milk (e.g. for 10 seconds at 73 °C) has a fine characteristic odour and sweet taste. Typical components present in low concentrations are dimethylsulfide, biacetyl, 2-methylbutan-l-ol, (Z)-hept-4-enal and ( )-non-2-enal. Milk pasteurised at higher temperatures and Ultra High Temperature (UHT) milk present the so-called cooked flavour, the appearance of which is the first measurable manifestation of the chemical changes that occur in heated milk. The substances responsible for the cooked off-flavour are sulfane and other sulfur compounds. Of particular importance are dimethylsulfide, dimethyldisulfide and dimethyltrisullide that are produced from proteins contained in the membranes of fat particles and from thiamine. Also relevant are alkane-2-ones (methylketones) generated by thermal decarboxylation of P-oxocarboxylic acids (mainly hexane-2-one, heptane-2-one and nonane-2-one), y-lactones and 5-lactones produced by dehydration of y- and 5-hydroxycarboxylic acids (mainly 8-decalactone and y- and 8-dodecalactones). Important carbonyl compounds include biacetyl, hexanal, 3-methylbutanal, (Z)-hept-4-enal and ( )-non-2-enal. In the more intensive thermal treatment of milk (sterilisation), products of the Maillard reaction play a role, such as maltol and isomaltol, 5-hydroxymethylfuran-2-carbaldehyde, 4-hydroxy-2,5-dimethyl-2 f-furan-3-one (furaneol) and 2,5-dimethylpyrazine. 

Chemists have demonstrated that maltol may be formed (1) by heating maltose at3758 F (191 C) for 1 hour (note the similarities of these conditions to those in baking), or (2) by heating mixtures of sugars, such as maltose and lactose, with amino acids, such as glycine (the latter procedure is known as nonenzymatic browning reaction of the Maillard type). 

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