Aroma burnt sugar

Detection thresholds (a = 50 %) in the model water-alcohol solution were 5 mg/1 and 2 mg/1 for maltol and cycloten respectively (Table IV). DDMP has a powerful burnt sugar aroma at the dry state or by sniffing the effluent of gas chromatography, but it is odorless in aqueous solutions as wine. We have still not been able to measure thresholds of other molecules DHM and furaneol could be some very interesting molecules. 

Alpha diketones 3-methyl-2-hydroxy-2-cyclo-penten-l-one a burnt sugar, roasted, lingering aroma. 

In strongly acidic media, saccharides produce furan derivatives in a sequence of reactions that are rearrangements and dehydrations followed by cyclization. Similar products are available thermally. Pentoses and hexoses give furan-2-aldehyde and 5-hydroxymethylfuran-2-aldehyde, respectively. Both of these products are responsible for the specific aroma of caramel and burnt sugar. 

This lactone is the flavoring compound formed by the aging of a-ketobutyric acid (Sulser et al., 1967). The flavor is described as malt, molasses, maple, burnt sugar (Chemisis, 1965), with a strong seasoninglike aroma at a concentration of 0.1 ppm and a taste threshold of 1-5 ppb for Sulser et al. (1972). Manley et al. (1980) reported a maple-like, remarkably persistent curry-like odor and wondered if the enolization or the instability of the compound could be responsible for the two notes. It is a potent odorant of roasted powder and brew of arabica coffee with odor descriptions similar to those of G.12, and an odor threshold of 2-4ng/m , air (Blank et al., 1992a,b), of 7.5 ppb in water (Semmelroch et al., 1995). 

The flavor of the tautomer mixture is perceived as burnt sugar, maple, cereal, chicory (Chemisis, 1978). The odor threshold reported by Semmelroch et al. (1995) was 1.15 ppm in water with a caramel-like quality. The odor threshold in air given by Blank et al. (1992b) was 0.5-1.5 p,g/m3. A flavor threshold of 21 ppb was reported by Huber (1992). By their enantioselective separation (see in 1.100), Bruche et al. (1995) determined that only one isomer of the less abundant tautomer 1.101b had a very intensive roasted almonds odor, the other isomer being less intensive of the two other tautomers, one is odorless, and the other reminiscent of the odorant 1.101b, is nearly odorless. Therefore ca 85 % of the mixture have no influence on the aroma. 

Certain 2-hydroxy substituted y-lactones (3-hydroxy furan-2-ones) derived from ycrotonolactone, however, have a specific odour. Typically 3-hydroxy-4,5-dimethyl-5//-furan-2-one (sotolon) has an aroma resembling fenugreek or curry at higher concentrations, and caramel, maple syrup or burnt sugar at lower concentrations. Sotolon occurs as a mixture of -)- R)-and (-F)-(S)-enantiomers (8-111). The perception threshold of (S)-sotolon (0.8 (xg/1) in a model wine solution was 100 times lower than that of the (l )-enantiomer (89 p-g/l), indicating that mainly (S)-sotolon contributes to the characteristic aroma of wines. The key component of acid protein hydrolysates is the higher... 

Chemical modification of simple sugars during drying, baking, or roasting operations can either have a desirable or undesirable effect upon the organoleptic quality of the final product. We have become accustomed to the characteristic roasted or baked flavors of coffee, peanuts, popcorn, and freshly-baked bread. The color and flavor and aroma of caramel make it a useful additive for the food industry. On the other hand, the burnt flavor of overheated dry beans or soy milk reduces marketability of these products. 

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