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12.9 Meat Aroma 605

via a separate fluid bed. The packaging materials

used protect the dry mixture from light, air, and

moisture.

12.9 Meat Aroma

Raw meat has only a weak aroma. Numerous

intensive aroma variations arise from heating,

the character of the aroma being dependent on

the type of meat and the method of preparation

(stewing, cooking, pressure cooking, roasting

or broiling-barbecuing). The preparation effects

are based on reaction temperatures and reactant

concentrations. Thus, a carefully dried, cold

aqueous meat extract provides a roasted meat

aroma when heated, while an extract heated

directly, without drying, provides a bouillon

aroma.

12.9.1 Taste compounds

Meat aroma consists of: (a) nonvolatile taste

substances, (b) taste enhancers and (c) aroma

constituents. The latter compounds or their

precursors originate essentially from the watersoluble

fraction. The constituents listed in

Table 12.22 have been identified as the taste

substances of beef broth and roasted meat

juice. Solutions of these substances in the given

concentrations (Table 12.22) give the typical

taste profiles, which are composed of sweet, sour,

salty, and glutamate-like (umami) notes. The

meat note is produced by odorants.

12.9.2 Odorants

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 octanal, nonanal, (E,E)-2,4-decadienal,

methanethiol, methional, 2-furfurylthiol, 2-methyl-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 12.22. Taste compounds in beef broth and pot

roast gravy

Concentration (mmol/l)

Compound/Ion Broth a Roast gravy b

Aspartic acid 0.05 0.18

Alanine – c 9.41

Glutamic acid 0.3 1.71

Cysteine – c 0.48

5 ′ -AMP 0.14 0.64

5 ′ -IMP 0.4 7.82

Hypoxanthine – c 3.62

Carnosine 6.2 23.4

Anserine 0.7 – c

Lactic acid 25.6 155

Succininc acid – c 2.16

Carnitine 2.0 – c

Pyroglutamic acid 2.6 – c

Creatinine – c 43.3

Creatine – c 20.3

Sodium 2.3 35.6

Potassium 31.3 170

Magnesium 3.0 12.1

Calcium 1.0 – c

Chloride 3.1 18.9

Phosphate 10.1 49.4

a Ground meat (500 g) suspended in 1 l of water and

boiled for 2 h, followed by fat separation and filtration.

b Meat (2 kg) fried for 20 min and braised for 4 h after

the addition of 1 l of water. The meat juice or gravy is

poured off.

c Does not contribute to taste in the sample.

in concentration exist. The meaty/caramellike

note typical of beef is produced by

2-furfurylthiol,2-methyl-3-furanthiol and HD3F,

which occur in relatively high concentrations in

this meat. In comparison, the lower concentration

of HD3F in pork is due to the considerably lower

contents of the precursors glucose 6-phosphate

and fructose 6-phosphate.

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

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