Thermal Food Processing

Thermal Processing of Fishery Products 249
TABLE 8.3
Effect of Sterilization Time on the Free Amino Acid Content
in Albacore Muscle (mg/100 Dry Weight)
Amino
Acid Fresh SD
however, when F = 13, significant differences were found, confirming the negative
effect of the sterilization time. These authors suggest that analysis of the free
amino acids would be useful to know the extent of thermal processing.
8.8.3 AMINES
8.8.3.1 Total Volatile Bases
Canned
115°, 60 min SD 115°, 100 min SD
Asp 36.9 4.7 32.7 4.2 32.1 4.4
Glu 55.7 5.2 49.3 4.8 37.3 5.1
Ser 34.5 5.8 30.5 5.0 31.0 5.4
His 2320.0 39.7 2050.1 37.6 1461.6 40.5
Gly 56.7 6.1 49.9 5.6 27.8 5.1
Thr 71.5 9.7 63.7 10.1 50.0 11.2
Arg 273.0 21.7 240.5 18.9 163.8 22.3
Tau 199.1 11.1 173.2 9.6 122.4 9.5
Tyr 49.3 3.6 42.4 3.9 31.0 3.4
Ala 80.6 3.2 70.2 3.8 58.9 4.0
Trp 97.1 4.1 83.6 4.4 76.7 3.8
Met 62.5 3.3 53.1 3.0 41.2 3.5
Val 26.6 3.1 23.6 2.9 16.0 2.8
Phe 150.5 3.9 134.0 3.3 117.5 3.0
Ile 48.1 5.1 40.9 4.3 38.4 3.6
Leu 68.8 5.7 60.2 5.1 48.1 4.9
Lys 109.3 5.6 95.2 4.8 81.1 5.1
Total 3740.2 a 3293.1 b 2434.9 c
Note: Values followed by the same letter are not significantly different. SD = standard
deviation, four samples. Albacore caught in 1985.
Source: Courtesy of Pérez-Martin, R.I. et al., Z. Lebensm. Unters. Forsch., 187,
432–435, 1988. With permission.
The total volatile basic amines (TVB-N) include trimethylamine (TMA), dimethylamine
(DMA), ammonia, and other volatile nitrogenous compounds associated
with the spoilage of marine products. TMAO is present in a large number
of fish and shellfish, and it is generally accepted that TMAO is the main source
of TMA and DMA. Endogenous enzymes in fish and exogenous enzymes produced
by bacteria during frozen or ice preservation are responsible for the reduction of