Sucrose Maillard reaction

The solubility and hygroscopicity of tagatose are similar to those of sucrose, but the viscosity of solutions is lower. As a reducing sugar it is less stable in acid conditions and liable to take part in Maillard reactions. 

The most efficient method for the clean hydrolysis of sucrose is by the use of invertase, leading to an equimolar mixture of glucose and fructose (invert sugar). The presence of salts increases the rate of thermal degradation of sucrose.337 The reaction is also possible in the presence of such heterogeneous acidic catalysts as zeolites.338 The hydrolysis of the glycosidic bond is the first step of a number of subsequent reactions that can occur on the glucose and fructose residues, such as dehydrations, combinations with amino acids (Maillard reaction), and many other chemicals or fermentation processes.339... 

Formation mechanisms of imidazoles in the Maillard reaction are not as well understood as those of other heterocyclic compounds. The role of a-amino carbonyl fragments as intermediates in imidazole formation was suggested in the reaction of sucrose and ammonia (43). In a study of a L-rhamnose/ammonia model system, which produced fifty-two imidazoles, it was proposed that an amino-hydroxy fragment was responsible for imidazole... 

A starch-glycine mixture, heated at 290°C, was significantly different from the starch control in its composition of alkoxyphenols and imidazoles in the involatile phase, and pyrazine, pyridine, methylpyridine, and dimeth-ylpyrroles in the volatile phase (Umano and Shibamoto, 1984). The neurotoxin 4(5)-methylimidazole appeared in the vapor phase when ammonia, but not amino acids, was the nitrogen source (Tomasik et al., 1989b). A corn starch-sucrose combination inhibited the Maillard reaction (Lee and Woo, 1988). 

Lee, J. T., and Woo, K. L. (1988). Effect of preventing the Maillard reaction between casein and glucose with corn syrup and sucrose. Korean J. Food Sci. and Technol. 20 526-535 (Food Sci. Technol. Abstr. 5A13, 1989). 

Trehalose, a disaccharide sweetener, 45-50 percent as sweet as sucrose, was given GRAS status in 2000. It is naturally found in mushrooms, honey, lobster, shrimp, and foods made with yeast. It has been used in Japan for decades, and is commercially produced from starch by bacterial enzymes.98 Besides its mild sweetening power, it maintains cell structure during freezing and dehydration of foods. It is a nonreducing sugar, so it does not participate in the Maillard reaction (will not brown) and helps to protect the color of processed foods.99... 

All excipient chemical reactions should be incorporated into the experimental design. For example, drugs that contain primary and secondary amines functionality undergo Maillard reactions with lactose and other reducing carbohydrates such as glucose and maltose under pharmaceutically reasonable conditions.This reaction should be considered during formulation development. Alternative excipients such as mannitol, sucrose, and trahalose, which are not subject to the Maillard reaction, should be used in place of lactose in such cases. 

For making light-coloured meringues, therefore, it is essential to use the non-reducing sucrose. This Maillard reaction is important in the storage of milk products, since cows milk contains 0.3 M lactose and the dietary value of various proteins is often limited by their lysine content. 

In the volatile fraction of heated glucose, Walter and Fagerson (1968) identified the unsaturated lactone, 2-buten-4-olide (G.7) for the first time in this reaction. In a study of model reactions (see Maillard reaction in Section 3.1), Baltes and Bochmann (1987a) identified G.l, G.7, G.8, G.9 and G.ll (MS data given), among more than 100 monocyclic furans (and ca 350 volatile compounds) in the reactions of serine and threonine with sucrose under conditions similar to coffee roasting. 

Mulders (1973c) identified 1-furfurylpyrrole in a cysteine/cystine ribose browning system, Shibamoto et al. (1979) in a D-glucose/ammonia model system, Ho and Chen (1999) in a Maillard reaction of threonine with ribose as a main volatile product, Baltes and Bochmann (1987b) when heating serine and/ or threonine with sucrose (and in coffee). According to Tressl et al. (1981c), this compound was also formed from 4-hydroxyproline and 2-furaldehyde. 

Guyot et al. (1998) studied the inhibitory activity of 5-caffeoylquinic acid, the main component of the chlorogenic acids (see Section 2.1.4) on the formation of alkylpyrazines in Maillard reactions with model systems valine or leucine and saccharose. Applying their results to green robustas, they concluded that the aroma quality increased when the chlorogenic-acids content decreased and when the sucrose content increased. 

---