Odorant, boiled beef

In the case of boiled beef the results of AEDA were compared with those of AECA. Table 16.4 indicates that they agreed except in three cases. The odour potencies of 4-hydroxy-2,5-dimethyl-3(2H)-furanone, 3-mercapto-2-pentanone and methional were more than one dilution step higher in AECA than in AEDA [56]. Most likely, portions of these odorants had been lost during concentration of the extract for AEDA. AECA was also used in studies on the aroma of pepper [55], coffee [57] and Camembert cheese [58]. 

Table 16.4 Potent odorants of boiled beef—comparison (AECA) with AEDA [56] of aroma extract concentration analysis...

Boiled beef and pork differ in their aromas. Beef smells more intensely meaty, sweet-caramel-like and malty, whereas pork is stronger in sulphurous and fatty odour notes [21, 37J. According to Table 6.29, the pronounced odour notes of beef are caused by high concentration of furaneol (no. 1), 2-furfurylthiol (no. 2), 3-mercapto-2-pen-tanone (no. 3) and 2-methyl-3-furanthiol (no. 6). Omission experiments confirmed that these volatiles and in addition octanal, nonanal, (E,E)-2,4-decadienal, are the key odorants of boiled beef [21 ]. The higher concentration of the caramel-like smelling furaneol (no. 1) in beef than in pork is due to higher levels of its precursors glucose-6-phosphate and fructose-6-phosphate [37],... 

Omission experiments [21 ] indicated that 12-methyltridecanal (no. 11) did not belong to the key odorants of boiled beef in spite of its high OAV (Table 6.29). Most likely... 

Kerscher, R., W. Grosch, Comparative evaluation of potent odorants of boiled beef by aroma extract dilution and concentration analysis, Zeitschrift Lebensmit. Untersuch. Forsch., 204(1), p. 3, 1997. 

Dilution analyses were used to elucidate the potent odorants (Table 12.23) of boiled beef and pork and of the meat and skin of fried chicken. Omission experiments (cf. 5.2.7) show that octanak nonanal, (E,E)-2,4-decadienal, methanethiol, methional, 2-furfurylthiol, 2-me-thyl-3-furanthiol, 3-mercapto-2-pentanone and HD3F are the key aroma substances of boiled beef. These compounds are also present in boiled pork and chicken, but species-specific differences... 

Table 12.23. Concentrations of odorants in boiled beef and pork and in fried chicken...

A brothy compound associated with boiled beef, 4-methylthiazole-5-ethanol (sulfurol), is a reaction flavor product from hydrolysis of vegetable protein. It is suspected that a trace impurity (2-methyltefrahydrofuran-3-thiol) in sulfurol is the actual beef broth character impact compound (15). Another reaction product flavor chemical, mercaptopropanone dimer, has an intense chicken-broth odor. A synthetic pyrazine, 2-pyrazineethanethiol, provides excellent pork character (15). 

A series of alcohols (C4 - Cll) were identified in the tail meat. Odor threshold concentrations were generally higher for alcohols than the aldehyde counterparts. Except for 1-pentanol, the remainder of alcohol peaks were very small and might not be significant in overall arctna of boiled crayfish tail meat. Josephson et al. (23-25) found l-octen-3-ol, an enzymatic reaction product derived from lipids, to be one of the volatile ccxnponents widely distributed in fresh and saltwater fish. The compound 2-butoxyethanol identified in crayfish tail meat (3) has been reported in beef products (26-27). GC aroma perception of standard 2-butoxyethanol gave a spicy and woody note, hence this compound could be an important flavor component of the boiled crayfish tail meat. 

Sulphurous and fatty odour notes predominated in the odour profile of boiled pork. It is assumed [37, 38] that the sulphurous (e.g. methanethiol) and fatty odorants (e.g. octanal, nonanal) are clearly perceptible in pork due to the much lower concentration of furaneol (Table 6.29). Although when compared to pork, the levels of octanal and nonanal were twice as high in beef (Table 6.29) the fatty odour note was weak. In particular the fourfold higher concentration of furaneol might have reduced the intensity of the fatty odour. 

The aroma of boiled pork is not as intensive as that of beef and the fatty note is more pronounced. The concentrations of the fatty smelling carbonyl compounds, e.g., hexanal, octanal and nonanal, are lower in pork, but in proportion to the concentrations of 2-furfurylthiol, 2-methyl-3-furanthiol and HD3F, they are higher than in beef. This difference appears to favor the intensity of the fatty note in the odor profile of pork. In chicken, the fatty notes become even more noticeable due to... 

Lipid components associated with meat fat, especially unsaturated aldehydes, play a significant role in species-characterization flavors. For example, ( ,Z)-2,4-decadienal exhibits the character impact of chicken fat and freshly boiled chicken (66). ( , )-2,6-Nonadienal has been suggested as the component responsible for the tallowy flavor in beef and mutton fat (63). 12-Methyltridecanal was identified as a species-specific odorant of stewed beef and provides a tallowy, beeflike flavor character (67). Aldehydes provide desirable flavor character to cooked meat, but they can contribute rancid and warmed-over flavors at high concentrations, resulting from autoxidation of lipids (68). 

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