Caramel characteristics

At low levels (5 mg/L), diacetyl is considered to add complexity to wine aroma since it can impart positive nutty or caramel characteristics, although at levels above 5 mg/L it can resuit in spoilage, creating an intense buttery or butterscotch flavour, and is perceived as a flaw. Microbial formation of diacetyl is a dynamic process and its concentration in wine depends on several factors bacterial strain, pH, wine contact with lees, SO2 content (Martineau and Henick-Kling 1995 Nielsen and Richelieu 1999). The sensory threshold for the compound can vary depending on the levels of certain wine components, such as sulfur dioxide. It can also be produced as a metabolite of citric acid when all the malic acid has been used up. However, diacetyl rarely taints wine to levels where it becomes undrinkable. 

Cyclotene (2-hydroxy-3-methyl-cyclopentenone, 3) and maltol (3-hydroxy-2-methyl-pyranone, 4) were easily identified as being responsible for OZ 1 and 3, with burnt sugar and caramel characteristics. These compounds have been previously identified in toasted oak wood by (20,21). 

A flavor is tried at several different levels and in different mediums until the most characteristic one is selected. This is important because the character of a material is known to change quaUty with concentration and environment. For example, anethole, ben2aldehyde, and citral taste different with and without acid. Gamma-decalactone has different characters at different levels of use. -/ fZ-Butyl phenylacetate with acid is strawberry or fmity without acid it is creamy milk chocolate. 2,5-Dimethyl-4-hydroxy-3-(2Fi)-furanone with acid is strawberry without acid it is caramel or meat. 

A wide variety of special malts are produced which impart different flavor characteristics to beers. These malts are made from green (malt that has not been dried) or finished malts by roasting at elevated temperatures or by adjusting temperature profiles during kilning. A partial Hst of specialty malts includes standard malts, ie, standard brewers, lager, ale, Vienna, and wheat caramelized malts, ie, Munich, caramel, and dextrine and roasted products, ie, amber, chocolate, black, and roasted barley. 

Essence of Vanilla.—The substance sold under this name is, properly, a spirituous extract of the vanilla bean. Many samples, however, are little more than alcoholic solutions of artificial vanillin, coloured with caramel. Some samples, which cannot be described as adulterated, contain a little coumarin or other odorous substance, added to varj- the characteristic vanillin odour and flavour somewhat. 

CeHgOs, Mr 128.13, was found in, e.g., fenugreek, coffee, sake, and flor-sherry. Its aroma characteristic changes from caramel-like at low concentrations to currylike at high concentrations. A method described for its preparation comprises condensation of ethyl propionate with diethyl oxalate and reaction of the intermediately formed diethyl oxalylpropionate with acetaldehyde. Acidic decarboxylation of the ethyl 4,5-dimethyl-2,3-dioxodihydrofuran-4-carboxylate gives the title compound [199]. 

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. 

Amongst furans are several compounds of great importance in fragrances and flavours. The rose owes some of its odour to a terpenoid furan, rosefuran, coffee some of its characteristics to furylmethanethiol and related compounds. Compounds like the 3-furanone derivative furaneol (10) are particularly interesting for their odours depend upon concentration— furaneol can seem to resemble pineapple, caramel, burnt toast etc. Furaneol is a dihydrofuran-3-one dihydrofuran-2-ones are obviously lactones and are usually dealt with as such. 

As a rule furan derivatives are considered important aroma constituents from a sensory point of view. They are mainly associated with sweet, fruity, nutty or caramel-like odor-impressions. The furans have no meaty characteristics, but it seems possible that they contribute to the overall odor of broiled and roasted meat. 

F Sweet bread-like, caramellic in proper dilution O "Characteristic"... 

O Characteristic pungent and penetrating O of GC eluates Pungent O Sour, greenhouse O 100°C Caramel, sweet 180°C Burnt sugar O Green, sweet... 

A caramel suitable for addition to certain carbonated beverages must have high color and high transparency. An example, given in Table III, showed a maximum at 450 mp, near the peak of the I. C. I. blue primary,6 and a decrease toward the red end, a characteristic of a high transparency. 

Numerous y- and 8-lactones were identified in Tokaji aszu grapes (Miklosy and Kerenyi, 2004 Miklosy et al., 2004). The odor notes of the y-lactones were described as resin- and caramel-like, roasted, or honey, while the 8-lactones exhibited characteristic notes of coconut, chocolate, and peach. The same lactones had been identified earlier from botrytized wines but not from normal wines (Schreier et al., 1976). Lactones are mostly found in oxidatively aged wines but seem to develop in fruit due to the oxidizing effect of B. cinerea, water loss, or Maillard reactions (Miklosy et al., 2004). 

Perhaps one of the most fascinating and complex chemical reactions involving carbohydrates is caramelization. For example, granulated sugar heated at a high temperature in the dry state eventually produces a dark, viscous mass which has a strong and characteristic flavor totally different from the sweet taste of sucrose. 

Maltol occurs as a white, crystalline powder with a characteristic caramel-butterscotch odor, and is suggestive of a fruity-strawberry aroma in dilute solution. One gram dissolves in about 82 mL of water, in 21 mL of alcohol, in 80 mL of glycerin, and in 28 mL of propylene glycol. 

Various Isopentyl-substituted pyrazines, such as 2-lsopentyl-3-methylpyrazine, 2-isopentyl-5-methylpyrazine, 2-isopentyl-6— methylpyrazlne, 2-i8opentyl-5,6-disiethylpyrazlne, 2-isopentyl-3,5-dimethylpyrazlne and 2-isopentyl-3,6-dimethylpyrazlne were identified from the thermal reaction of glucose and leucine (12). The formation mechanisms for these compounds may also involve the reaction of 3,6-dihydropyrazine with isovaleraldehyde, the Strecker aldehyde of leucine. Kltamura and Shibamoto (13) described 2-lsopen-tyl-5,6-dimethylpyrazlne as having a caramel-like, coffee and sweet aroma. Although isopentyl-substituted pyrazines have not yet been reported in cocoa, they could, if present, be very Important contributors to that characteristic aroma. 

White crystalline solid with a characteristic, caramel-like odor and taste. In dilute solution it possesses a sweet, strawberry-like or pineapple-like flavor and odor. 

The emulsifiers influence the whipping quality of the mix. They produce a dry, smooth and stiff finished product. The dryness is often related to the impression of textural creaminess and warm eating characteristics in the mouth. Flavours such as caramel or vanilla may be chosen to complement this warm eating characteristic. This is as opposed to fruit flavours which may be better showcased in a crisp, refreshing and somewhat colder eating system [9, 10]. 

The volatiles detailed in Table 6.43 were identified in French fries prepared in palm oil [78, 79[. The flavour profile of a solution of these compounds in odourless sunflower oil was close to that of the original (Table 6.44). The greatest intensity differences were found for the caramel and malty notes when the model was retrona-sally examined. Variation of the composition of the aroma model indicated the odorants that are essential for the characteristic aroma [79[. An extract of the results is shown in Table 6.45. 

In a report, Hellwig and coworkers attempted to standardize particular types of caramel by means of the following tests (a) with citric acid, (b) solubility in 65% (v ) ethanol, and (c) the Lassaigne test (see Table 11). They also presented gel-permeation (g. p.) chromatograms (size exclusion chromatography) of various types of caramel. Values of for zones on the chromatograms evidently characteristic for the caramels studied are attributable to color components of caramel. These studies were directed to caramels standardized by ITCA. They allow division of these caramels into ten types and into further subtypes (see Table III). 

Analytical Characteristics of All Classes, Sorts, Types, and Sub-groups of Caramel Colors ... 

The authors observed that an exhaustive list of all the chemicals present in coffee flavor had not yet been compiled, but they believed they had identified the components that are present at the higher ratio of weight, and those which principally control the odor note. Most of the substances identified were well-known compounds present in other roasted products as well, for instance in caramel sugar, cocoa, baked bread and—partially—even in wood tar. However, some of the chemicals detected were new and, obviously, characteristic of roasted coffee. Traces of methyl mercaptan, which was already known at that time and which smells even worse, were also detected in coffee aroma. Commenting on this observation, Reichstein and Staudinger note that it is generally known that many popular raw materials and synthetic perfume compounds owe their characteristic note, which is extremely pleasant to the olfactory sense, to their content of small quantities in additives which carry a rather unpleasant odor in themselves but prove very attractive in thinned solutions and in admixture with other oils. The authors tried to reconstitute coffee aroma, and only by combining over 40 of the substances extracted from coffee... 

It has a strong caramel-like odor (Shaw et al., 1968), sweet, sugary at 1 ppm in water (Nishimura and Mihara, 1990). The flavor is maple, caramel, weak (Chemisis, 1967). Fors (1983) reported enhancing flavor characteristics. 

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