Volatile sulfur-containing meat flavor

Isolation and Characterization of Volatile Sulfur-Containing Meat Flavor Components in Model Systems... 

Werkhoff P., Bruning J., Emberger R., Guntert M. et ah (1990) Isolation and characterisation of volatile sulfur-containing meat flavor components in model systems. J. Agric Food Chem. 38, 777 91. 

Table I. Chemical Classes of Volatile Sulfur-Containing Components in a Model Meat Flavor System...

Table II. Volatile sulfur-containing components identified in a model meat flavor system...

Golovnya R.V., Misharina T.A., Garbuzov V.G. and Medvedev F.A. (1983) Volatile sulfur-containing compounds in simulated meat flavor and comparison of their composition with volatile compounds of natural boiled beef. Nahrung 27(3), 237-49. (Chem. Abstr. 99, 4241w)... 

A heterocyclic sulfur-containing compound, 2-methyl-thiophene, was identified in boiled crayfish tail meat and pasteurized crabmeat. Thiazole and 3-methylthiopropanal were identified in the crayfish hepatopancreas. Heterocyclic sulfur-containing compounds play important roles in generating meaty aromas in a variety of meat products and are considered important volatile aroma components of marine crustaceans (12— 14). The 2-methylthiophene could be an important flavor cemponent in boiled crayfish tail meat. Both thiazole find 3-methylthiopropanal were important contributors to the desirable meaty aroma associated with crayfish hepatopancreas. The 3-methyl-thiopropanal, identified in boiled crayfish hepatopancreas, is derived from Strecker degradation of methionine (15), and has been considered to be an important cemponent in basic meat flavor (16). Pyridine was detected in the headspace of the hepatopancreas from freshly boiled crayfish. Pyridine and 2-ethylpyridine have been previously reported as components in the atmospheric distillate from a sample of crayfish hepatopancreas frozen for three months (2). 

Volatile profiles of raw and cooked-beef flavor samples, prepared by the procedures of Figure 1, were obtained after capillary GC and FPD. Although the identification of these sulfur containing compounds is as yet incomplete, the chromatograms demonstrated that there were a number of new sulfur compounds produced on cooking that were not present in the raw beef. Three prominent sulfur compounds were identified as markers in subsequent meat flavor deterioration experiments, namely, methional (13.2 min), methyl sulfone (13.8 min), and benzothiazole (25.3 min). Each compound produced an adequate mass spectrum for spectral library search and positive identification. 

By way of contrast, a total of 70 sulfur-containing compounds were identified in the volatile components isolated from our model meat flavor system. A rough survey of the chemical classes represented in the processed meat aroma is shown in Table I. 

In summary, model studies are very efficient for the identification and structure elucidation of important flavor components. Most of the compounds reported here have not been identified in meat and have not yet been reported as constituents of food volatiles. Nevertheless, there are good reasons to believe that minute traces of these sulfur-containing components are present in roasted and/or cooked meat volatiles because our model system was based solely on naturally occurring precursors. We believe that only minute trace amounts of these types of components need to be present in natural products to be of prime significance due to their extremely low odor threshold values. 

Meat flavor is due to a great number of volatiles from different chemical classes. However, most of the odorants described as meaty aroma contain sulfur. The two most important reactions which generate meaty aroma compounds are the reactions between sulfur containing amino acids and reducing sugars (Maillard reaction) and the thermal degradation of thiamin [35], Sulfur-containing furans are the basic chemicals responsible for the aroma of thermally treated meat. 

Antioxidative Properties. When cooked meat is refrigerated, a rancid or stale flavor usually develops within 48 hrs. This character has been termed warmed-over flavor (WOF) and is generally attributed to the oxidation of lipids. Various synthetic and natural antioxidants have been used to reduce the development of WOF. Among the natural antioxidants used are the sulfur containing amino acid cysteine, and various Maillard reaction products. Eiserich and Shibamoto (Chapter 20) found that certain volatile sulfur heterocycles derived from Maillard reaction systems can function as antioxidants. 

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