In boiled beef

Oxazoles have been found in relatively few cooked foods, although over 30 have been reported in coffee and cocoa, and 9 in cooked meat. Oxazolines have been found in cooked meat and roast peanuts, but not to any extent in other foods. 2,4,5-Trimethyl-3-oxazoline has been regularly detected in cooked meat [26], and when it was first identified in boiled beef [27] it was thought that the compound possessed the characteristic meat aroma however, on synthesis it was shown to have a woody, musty, green flavour with a threshold value of 1 mg/kg [28]. Other 3-oxazolines have nutty, sweet or vegetable-like aromas and the oxazoles also appear to be green and vegetable-like [28]. The contribution of these compounds to the overall aroma of heated foods is probably not as important as the closely related thiazoles and thiazolines. 

Chang et al. (42). They Isolated and identified 2,4,5-triinethyl-3-oxazoline in boiled beef. This compound was described as having a "characteristic boiled beef aroma". Mussinan et al. (35) identified oxazolines and no oxazoles in their beef system. Peterson et al. (43) reported on the volatiles of canned beef stew. Both 2,4,5-trimethyloxazole and 2,4,5-trimethyl-3-oxazoline were present. The relative concentration of 2,4,5-trimethyloxazole was medium while for 2,4,5-trlmethyl-3-oxazoline was extra high. Lee et al. (44) identified 2-methyl-3-oxazoline, 2,4-dimethyl-3-oxazoline and 2,4,5-trimethyl-3-oxazoline in the volatiles of roasted peanuts. The latter two 3-oxazollnes were also identified in the volatiles of fried chicken (19). 

As many oxazolines (but only one oxazole, trimethyloxazole, L.ll) were identified in beef systems, always heated at lower temperatures than those used for coffee roasting, it seems reasonable to consider them as intermediates in oxazole formation. Hirai et al. (1973) and Peterson et al. (1975) actually observed that the peak area for 2,4,5-trimethyl-3-oxazoline is large to very large in boiled beef extracts. The work of Jassmann and Schulz (1963) had previously shown that this 2,4,5-trimethyl-3-oxazoline results from thermal interaction of ammonia, acetaldehyde and acetoin, all compounds that have been reported to be present in cooked beef, as well as in coffee volatiles. 

Hirai C., Herz K.O., Podkorny J. and Chang S.S. (1973) Isolation and identification of volatile flavor compounds in boiled beef. J. Food Sci. 38, 393-7. 

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

To illustrate the utility of SPME-MS-MVA for QC food applications, consider how it can be applied to monitoring the development of WOF in boiled beef. 

We performed collaborative studies using the ELISA methods with model processed foods (sausage, boiled beef in an aluminum pouch, tomato sauce, biscuit, juice, and jam) containing allergen proteins. The six... 

The most important sulfur heterocycles with a five-membered ring and three sulfur atoms are the diastereomeric 3,5-dialkyl-1,2,4-trithiolanes 6. The dimethyl derivatives (6, R - Me) have been found in various cooked foods, such as mushrooms (41), boiled beef (42) commercial beef extract (43), boiled antarctic krills (44), red algae (45), and several model systems containing a source of sulfur (2,19,29), The diethyl derivative (6, R - Et) was identified by Ledl (33) and by Sultan, with propionaldehyde as the starting material. The dipropyl and diisopropyl derivatives (6,... 

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]. 

Wilson, el al. (41) also confirmed the presence of polysulfur heterocyclics in meat including thialdine (5,6-dihydro-2,4,6-tri-methyl-l,3,5-dithiazine) and trithioacetone (2,2,4,4,6,6-hexame-thyl-1,3,5-trithiane). Wilson (42) later discussed the possible routes of formation of some of these compounds from cysteine. Thialdine was found by Brinkman, et el. (43) in the headspace volatiles of beef broth. These workers also identified 3,5-di-methyl-1,2,4 - trithiolane from the same source. Both cis and trans isomers of this compound had previously been identified as flavor components of boiled beef by Chang, jit aL. (44) and Herz (45). 

F Roasted, nutty, meaty O Sulfury as in meat F Boiled beef, chicken and turkey... 

Trithiolanes have received increasing attention since the identification of diastereomeric 3,5-dimethyl-l,2,4-trithiolane in the volatiles of boiled beef (13). The parent 1,2,4-trithiolane is a component of Shiitake mushrooms (14) and red algae (15). In addition to 3,5-dimethyl-l,2,4-trithiolane, Kubota et al. (16) identified 3-methyl-5-ethyl-l,2,4-trithiolane and 3,5-diethyl-l,2,4-tri-thiolane in both syn and anti forms in boiled Antarctic Gulls. Both compounds were described as garlicky. Flament and co-workers (17) reported the identification of 3-methyl-5-ethyl-l,2,4-trithiolane and 3-methyl-5-isopropyl-l,2,4-trithiolane in a commercial beef extract. ... 

The calcium content of the meals was increased by adding milk or lowfat cheese. In the studies on the effect of protein, the animal protein sources were milk, cheese, boiled beef and boiled egg. To further increase, the protein content without at the same time increasing the calcium or zinc content, sodium caseinate was used in one meal. 

Butylamine occurs naturally in some foods. These include kale (7ppm) pickles cucumbers in aromatic vinegar (0.6 ppm) cucumbers pickled with mustard (5.3 ppm) Tilsiter cheese (3.7ppm) brown bread (1.1 ppm) mulberry leaves fish and seafood. n-Butylamine has been identified as a volatile component of boiled beef. Butylamines have been reported to be a component of animal waste, perhaps from decomposition of manure. 

The Middle Notes are based on reaction flavourings to impart specific complex roasted, meaty and smoky notes roasted chicken, boiled beef, smoked ham. They improve the overall taste with a general meaty background and a good mouthfeeling. Meaty middle notes are often based on the reaction of vitamin Bl, cystein and reducing sugars. Fat included in the reaction modifies the product into a specific animal direction chicken, beef, mutton, pork. 

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... 

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)... 

It is best obtained from the flesh of the fowl, which contains 0.82 per cent., or from beef-heart, which contains 0.14 per cent. It is soluble in boiling HjO and in alcohol, insoluble in ether crystallizes in brilliant, oblique, rhombic prisms neutral, tasteless, loses aq at lOO (313 P.) fuses and decomposes at higher temperatures. When long heated with HiO or treated with concentrated acids, it loses HaO, and is converted into ereatinin. Baryta water decomposes it into sarcosin and urea. It is not precipitated by silver nitrate, except when it is in excess and in presence of a small quantity of potassium hydroxid. The white precipitate so obtained is soluble in excess of potash, from which a jelly separates, which turns black, slowly at ordinary temperatures, rapidly at 100° (212 P.). A white precipitate, which turns... 

Such transformations appeared regularly in the literature of the time, often as brief reports. Phipson (1862) compared the chemical and biological oxidations of citric acid. Permanganate was the chemical oxidant which produced oxalic acid uncooked putrid beef and boiled beef were the biological agents which yielded butyric acid (Scheme 1.3). It is not surprising that the analysis of these transformations (Scheme 3) should differ from a modern interpretation. 

Despite the acknowledged importance of these furan- and thiophenethiols and their disulfides in meat-like flavors, it is only recently that compounds of this type have been reported in meat itself (8-10). Grosch and co-workers (11) have suggested that the 2-methyl-3-furanthiol and its disulfide are more important in the aroma of boiled meat than in roast beef where alkylpyrazines, 2-acetyl-2-thiazoline and 2,5-dimethyl-4-hydroxy-3(2 -fiiranone make greater contributions. 

Recent studies of photooxidized butter and butter oil identified by aroma extract dilution analysis, 3-methylnonane-2,4-dione, a potent volatile compound derived from furanoid fatty acids (see Section C.4) (Figure 11.7). Six different furanoid fatty acids were established as dione precursors, and were found in various samples of butter made from either sweet cream (116 76 mg/ kg), or from sour cream (153-173 mg/kg), or from butter oil (395 mg/kg). Similar precursors of the dione were identified in stored boiled beef and vegetable oils. This flavor defect arising by photooxidation of butter or butter oil is apparently different from the light-activated flavor in milk,that involves the interaction of sulfur-containing proteins and riboflavin. However, more sensory comparisons are needed to distinguish between these two flavor defects due to light oxidation. 

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... 

Cyanide ion, CN , is gaining impmtance as an ionic CO analog. It has been found as ligand for the active-site ircm in a number of hydrogenases (Chapter 16). Its complexes date back to alchemical times. Diesbach, a Berlin draper, boiled beef blood in a basic medium to obtain the dye, I ssian blue, still in common use. It was later shown to be a coordinaticHi polymer containing Fe —C=N—Fe units note how tlie softer Fe(II) binds the softer C end of cyanide. This can claim to be considm-ed both the first oiganometalHc and the first coOTdination compound. 

Few researchers have examined the effects of different cooking methods on the aroma of cooked meat. MacLeod and Coppock [14] compared the aromas of boiled and roasted beef using SDE. They suggested that carbonyl compounds, sulfides, pyrroles, and pyridines were associated with roasted aroma, whereas benzenoids and furans may be associated with the desirable qualities of well-cooked boiled beef In the experiment we describe here, headspace adsorption on Tenax TA was used to compare the aroma profiles of pressure-cooked and grilled lamb muscle. 

SPME-MS-MVA applications reported to date have used the Varian Saturn ion trap mass spectrometer and 75- J,m Carboxen/PDMS as the SPME fiber (13,14). In one study, for example, SPME-MS-MVA was used to classify various types of food samples according to the level of oxidized off-flavors they contained (14). Mass fragmentation data resulting from the unresolved food volatile components were subjected to MVA. The mass intensities from m/z 50 to m/z 150 were selected to perform MVA. PGA based on SPME-MS-MVA provided rapid differentiation of the following types of samples control soybean oil from oxidized soybean oil that was exposed to fluorescent light for various time periods control nondairy coffee creamer from complaint ( oxidized ) nondairy coffee creamer samples fresh boiled beef from boiled beef with various levels of warmed-over flavor (WOE) and control 2% reduced-fat milk samples from 2% reduced-fat milk samples abused by light or copper exposure. 

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