As mentioned, 4-MeI is neurotoxic and is produced in the ammonia caramels. Thus, many studies are focused on developing nonammonia caramels with similar or higher tinctoreal power. Particularly, the use of MgO induces a 150% increase in the tinctoreal power. It is suggested that MgO destroys the coat of melanoidin micelles, which enter into subsequent condensations and eliminations. The chro-mophore of caramel is extended and its tinctoreal power is increased as well as the content of the coloring matter.33 Glycine and sodium glycinate are effective catalysts to obtain caramel of good tinctoreal strength; the highest effect was obtained at levels of 2% w/v of glycine or 5% w/w of sodium glycinate. However, these prepared caramels exhibit a different flavor and aroma from ammonia caramels.34 Asparagine, histidine, and serine are also used for caramel preparation; in addition the sodium salts of these amino acids are appropriate for coloring beverages but not soft, sour drinks.35

Aspartame (L-aspartyl-phenylalanine-1-methyl ester) (a-ASM) is commonly used as a sweetening ingredient in food and beverages; it is 200 times sweeter than sucrose. One of its applications is in the preparation of diet cola, where caramel color is also used. Interestingly, it has been reported that the presence of 1400 ppm of caramel color reduces the half-life of a-ASM resulting in a 25 to 37% lower halflife than control samples. This phenomenon has not been observed at caramel levels less than 700 ppm. It is suggested that at high caramel IV concentration, micelles are formed with the sulfonate groups outside and consequently a high negative charge

Was this article helpful?

0 0

Post a comment