Skipjack tuna

Yoshinaga DH, HA Frank (1982) Histamine-producing bacteria in decomposing skipjack tuna (Katsuwonus pelamis). Appl Environ Microbiol 44 447-452. 

Skipjack tuna, Euthynnus pelamis-, muscle Peru... 

The effect of temperature on histamine formation has been the subject of many studies (Table 6.5). Different studies reported 100-fold variations in histamine concentrations in skipjack tuna allowed to spoil under similar conditions. Although the information in Table 6.5 contains substantial variation, it is obvious that longer storage times and higher temperatures seem to induce histamine production. Control of biogenic amine production by low temperatures (for example 0°C) is consistently observed. 

Arnold, S.H., Price, R.J., and Brown, W.D. (1980). Histamine formation by bacteria isolated from skipjack tuna, Katsuwonas pelamis. Bull. Jpn. Soc. Sci. Fish. 46, 991-995. 

Staruszkiewicz, W., Barnett, J., Rogers, R., Benner Jr, P., Wong, L. and Cook, J. (2004). Effects of on-board and dockside handling on the formation of biogenic amines in mahi mahi (Coryphaena hippurus), skipjack tuna (Katsuwonus pelamis), and yellowfin tuna (Thunnus albacares), J. Food Prot., 67, 134. 

The results given below were collected in a study of decomposition in skipjack tuna (Katsuwonus pelamis) under controlled incubation conditions and were described in part previously (, 25). Skipjack was chosen as the test species for this investigation because ... 

An adequate supply of live skipjack tuna was available locally. By incubating the fish immediately after expiration, we avoided undesired postmortem spoilage changes caused by improper handling before incubation. 

Live skipjack tuna were allowed to expire, placed separately in plastic bags containing seawater, and incubated for the times desired at various temperatures. After incubation, samples of tissue were removed for various bacteriological analyses and histamine estimations. 

Fresh skipjack tuna contained about 0.1 mg of histamine per 100 g... 

Figure 1 shows the extent of histamine formation in whole skipjack tuna at temperatures over the range of 15.6 C to 48.9 C. After incubation for 24 h, samples were taken from the anterior section of... 

Histamine Distribution in Decomposed Tuna. The level of histamine produced is not uniform throughout decomposed fish ( 2, 30, 36). In spoiled skipjack tuna, we found a histamine gradient that was highest in the anterior section and decreased gradually in sections approaching the tail (, 2. ... 

Figure 1. Effect of incubation temperature on histamine formation in skipjack tuna.

Figure 2 shows the amounts of histamine in four sections of skipjack tuna incubated at 38°C, the optimum temperature for decomposition (Figure 1). Histamine was found first in the anterior section, exceeding 100 mg per 100 g at 12 h, and reached 680 mg by 24 h. Histamine production was slower in the remaining sections and did not reach significant levels until 18 h of incubation had elapsed. A histamine gradient was evident at 24 h, with the highest level in the anterior section.

The intestine is believed to be a major source of bacteria responsible for histamine formation in skipjack tuna (25). The higher level and rate of histamine formation in the anterior section are related to the location of the intestinal tract in the forward end of the fish. Postmortem disintegration of the intestine liberates its microbial contents into the visceral cavity and anterior muscle tissue. 

Bacterial Growth and Histamine Formation. The quantitative relationship between histamine formation and the microbial flora in skipjack tuna at 38 C is shown in Figure 3. At intervals during incubation samples were removed from the second section and assayed for histamine content and bacterial numbers. After 24 h the anaerobic bacterial count was 3.5 x 10 per g, and the histamine content was 297 mg per 100 g. Anaerobic counts were used to measure the microbial population because over 92% of the bacteria found in decomposed skipjack tuna were obligate or facultative anaerobes (Table I). 

Table I. Bacteria Isolated From Decomposed Skipjack Tuna...

Figure 2. Histamine distribution in sections of skipjack tuna at 38 C. Section legends = anterior A= second = third = posterior.

Figure 3. Bacterial growth and histamine formation in skipjack tuna at 38 °C. Reproduced with permission from Ref. Copyright...

Identification of Spoilage Microflora Table I lists the bacteria recovered from decomposed skipjack tuna after incubation for 24 h at 38°C. Eighteen of the 134 bacteria isolated were histamine formers, and these strains consisted of obligate and facultative anaerobes. 

Discarded fish bones and cutoffs may contain considerable amounts of muscle proteins. These muscle proteins are nutritionally valuable and easily digestible with well-balanced amino acid composition (Venugopal et al., 1996). Therefore, fish proteins derived from seafood processing by-products can be hydrolyzed enzymatically to recover protein. Protein hydrolysates from several marine species have been analyzed for their nutritional and functional properties, and researches have mainly explored the possibility of obtaining biologically active peptides (Benkajul and Morrissey, 1997). Moreover, skipjack tuna muscle (Kohama et al., 1988), sardine muscle (Bougatef et al., 2008), and shark meat (Wu et al., 2008) have been used to separate potential peptides. 

Brill, R.W. and Dizon, A.E. (1979). Red and white muscle fibre activity in swimming skipjack tuna, Katsuwonus pelamis. Journal of Fish Biology 15,679-685. 

Rayner, M.D. and Keenan, M.J. (1967). Role of red and white muscle in the swimming of skipjack tuna. Nature, bond. 214,392-393. 

Stevens, E.D., Lam, H.M. and Kendall, J. (1974). Vascular anatomy of the counter-current heat exchanger of skipjack tuna. Journal of Experimental Biology 61,145-153. 

East China Sea Skipjack tuna 1996-2001 PBDEs11 21 ng g-1 lipid Uneo et al., 2004... 

Uneo, D., Kajiwara, N., Tanaka, H., Subramanian, A., Fillmann, G., Lam, P.K.S., Zheng, GJ., Muchitar, M., Razak, H., Prudente, M., Chung, K.H., Tanabe, S., 2004. Global pollution monitoring of polybrominated dipheynl ethers using skipjack tuna as a bioindicator. Environ. Sci. Technol. 38, 2312-2316. 

Concentrations of BFRs (PBDEs and HBCDs) and OCs in the muscle and liver of skipjack tuna collected from the offshore waters of various regions in the world, including the Philippines were recently conducted... 

Table 12.4. Concentrations of PBDEs, HBCDs and OCs (ng g 1 fat wt.) in the liver of skipjack tuna collected from offshore waters and open seas...

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