酶解法从黄鳍金枪鱼鱼头中提取鱼油的研究

利用蛋白酶酶解法从黄鳍金枪鱼加工的下脚料--鱼头中提取鱼油.以鱼油提取率为指标,选择合适的蛋白酶,研究了酶解工艺条件对提取率的影响.研究结果表明:胰蛋白酶提取鱼油的酶解工艺参数为酶解温度50℃,酶添加量1%,底物浓度1:1,酶解时间4h,酶解pH值8.在此条件下,粗鱼油的提取率为4.22%,理化指标达到了SC/T3502-2000的粗鱼油二级标准,多不饱和脂肪酸总含量高达38.47%,其中DHA和EPA的含量分别为23.63%和4.84%.     

Characteristics of Gelatin Extracted from the Swim Bladder of Yellowfin Tuna (Thunnus albacores) as Affected by Alkaline Pretreatments

ABSTRACT

Gelatins extracted from the swim bladder of yellowfin tuna (Thunnus albacores) using various alkaline pretreatments were characterized. Alkaline mixtures (Na₂CO₃:NaOH) at different ratios (9:1, 8:2, 7:3, and 6:4) with a concentration of 4% (w/v) were used. The corresponding gelatins termed “G1,” “G2,” “G3,” and “G4” had yields of 9.78, 14.91, 35.96, and 13.60% (dry weight basis), respectively. All gelatins had α-chains as the major components. Fourier transform infrared spectra of obtained gelatins revealed the significant loss of molecular order of the triple-helix. G3 having the highest imino acid content and exhibited the highest gel strength (p < 0.05), compared with others. The microstructure of G3 gel was finer with smaller voids, compared with others. With increasing proportion of NaOH, the L*-value of gelatin gel increased with coincidental decrease in ΔE*-value. Gelling and melting temperatures of swim bladder gelatin were 12.3–15.1 and 21.3–22.3°C, respectively.     

世界黄鳍金枪鱼渔业现状和生物学研究进展

黄鳍金枪鱼(Thunnus albacares)是金枪鱼渔业的重要经济鱼种。文章叙述了世界黄鳍金枪鱼最近20多年来的渔业历史和现状,并按照不同渔具对黄鳍金枪鱼在各海区的渔业历史和现状进行了分析。叙述了渔场时空分布以及各海区主要从事黄鳍金枪鱼作业国家的渔业产量。此外,还对黄鳍金枪鱼的分布、洄游、种群、生长、繁殖及食性等基本生物学特性进行了综述。     

Protein Hydrolysate from Visceral Waste Proteins of Bolti Fish (Tilapia nilotica): Chemical and Nutritional Variations as Affected by Processing pHs and Time of Hydrolysis

The main objective of the current work was to evaluate the proximate chemical composition and nutritional quality of amino acids of protein hydrolysates from viscera of Tilapia nilotica fish. The results of amino acid composition showed that all hydrolysates contained sufficient and/or excessive amounts of both essential and nonessential amino acids, with appreciable values of essential amino acid/nonessential amino acid ratio (0.77 to 1.59) and essential amino acid/total amino acid ratio (43.35 to 61.35). All protein hydrolysates had a high content of the flavor enhancer amino acids. The lowest values of essential amino acids were found for phenylalanine and methionine with chemical scores ranging from 0.04 to 0.77 and 0.09 to 1.06, respectively, except for 18 h hydrolysates. The protein efficiency ratio had values greatly exceeding 2.0, which is considered a high quality. On the other hand, the levels of sugar and ash contents ranged from 2.69 to 3.32 g L^?1 and 0.48 to 2.1%, respectively, with 9.2 to 14% dry matter. Mineral composition showed that sufficient amounts of calcium, sodium, potassium, magnesium, and iron were present. The results suggest that the studied hydrolysates are appropriate for use in balanced human or animal diets.     

大眼金枪鱼渔业现状和生物学研究进展

结合各海区大眼金枪鱼的产量,对大眼金枪鱼在各海区的渔业历史和现状,按照不同渔具进行了分析。并对其分布、运动模式、牛理特性、年龄和生长、繁殖、食性以及种群结构等生物学作了具体的阐述。     

Comparison of the behavior of skipjack (Katsuwonus pelamis), yellowfin (Thunnus albacares) and bigeye (T. obesus) tuna associated with drifting FADs in the equatorial central Pacific Ocean

We evaluated the behavior of skipjack (Katsuwonus pelamis), yellowfin (Thunnus albacares) and bigeye tuna (T. obesus) associated with drifting fish aggregating devices (FADs) in the equatorial central Pacific Ocean. A total of 30 skipjack [34.5–65.0 cm in fork length (FL)], 43 yellowfin (31.6–93.5 cm FL) and 32 bigeye tuna (33.5–85.5 cm FL) were tagged with coded transmitters and released near two drifting FADs. At one of the two FADs, we successfully monitored the behavior of all three species simultaneously. Several individuals remained around the same FAD for 10 or more days. Occasional excursions from the FAD were observed for all three species, some of which occurred concurrently for multiple individuals. The detection rate was higher during the daytime than the nighttime for all the species, and the detection rate for bigeye tuna was higher than for yellowfin or skipjack tuna. The swimming depth was deeper during the daytime than nighttime for all species. The fish usually remained shallower than 100 m, but occasionally dived to around 150 m or deeper, most often for bigeye and yellowfin tuna during the daytime. The swimming depth for skipjack tuna was shallower than that for bigeye and yellowfin tuna, although the difference was not large, and is probably not sufficient to allow the selective harvest of skipjack and yellowfin tuna by the purse seine fishery. From the detection rate of the signals, bigeye tuna is considered to be more vulnerable to the FAD sets than yellowfin and skipjack tuna.     

Considerations of stock structure of yellowfin tuna (Thunnus albacares) in the Indian Ocean based on fishery data

Yellowfin stock structure in the Indian Ocean was studied by using industrial tuna longline fishery data. Three types of test variables were used to detect stock structure, i.e., CPUE, age-specific CPUE, and coefficient of variation for size. Time-series data of test variables were compiled for six sub-areas that were arranged by dividing the whole region systematically along longitude lines every 20 degrees. Then time-series data were smoothed by moving averages, and regressed by simple models. Patterns of time-series trends were graphically and statistically compared to classify homogeneous sub-area groups. Two assumptions were (a) that homogeneous stocks exist longitudinally and overlap in adjacent waters, and (b) that test variables within homogeneous sub-area groups are equally affected, and hence patterns of the time-series trends are similar. After graphical screening for significant sub-area groups, analysis of covariance was applied to test homogeneity of regression parameters representing patterns of the time-series trends. By classifying homogeneous sub-area groups, stock structures were determined at the P <0.05 and P <0.50 levels. The P<0.50 level was recognized as a useful criterion for ‘weak’ test variables since masked or vague structures at the P <0.05 level were likely cleared at this level in many cases. Results of this study and past stock structure studies were reviewed and compared. It was concluded that there are two major and two minor stocks of yellowfin tuna. The two major stocks (the western and the eastern) are located at 40^o-90^oE and 70^o-130^oE respectively. The minor stocks are the far western and the far eastern stocks (the latter possibly being a part of the Pacific stock), which are located westward of 40^oE and eastward of 110^oE respectively. Neighboring stocks are intermingled in adjacent waters.     

Comparative intestinal absorption of amino acids in rainbow trout (Oncorhynchus mykiss), totoaba (Totoaba macdonaldi) and Pacific bluefin tuna (Thunnus orientalis)

The kinetics of amino acid absorption in the proximal section of three fish species were studied using an everted intestine technique and a pancreatic digest of casein (Tryptone), as the model amino acid mixture. Fresh intestine of rainbow trout (Oncorhynchus mykiss) was used to set up the experimental system, and results were compared with those obtained using intestines from totoaba (Totoaba macdonaldi) and bluefin tuna fish (Thunnus orientalis). The kinetics of amino acid absorption was sigmoidal for all amino acids and for each species of fish tested. In general, specific absorptions of essential amino acids were higher than those of non‐essential ones. No correlation between the concentration of amino acids in the Tryptone solution and the corresponding absorptions was found. The maximum specific absorption rates of all amino acids for trout were 10 times higher than those determined for totoaba and bluefin tuna. The relative amounts of the different amino acids preferentially absorbed in all three species were different. Results obtained from the everted technique may be applicable to the design of formulated diets for large fish species with commercial value.     

In vitro amino acid absorption using hydrolysed sardine muscle or soybean meal at different intestinal regions of the Pacific bluefin tuna (Thunnus orientalis)

The amino acid (AA) absorption along the intestinal tract of the Pacific bluefin tuna (Thunnus orientalis) was evaluated using two hydrolysed protein sources (fresh sardine muscle and soybean meal) with the everted intestine technique. Pork pepsin and pancreatic enzyme extract from the bluefin tuna were used to hydrolyse the protein from fresh sardine (FSH) and soybean meal (SMH) under optimal bluefin tuna fish physiological conditions. Both of the hydrolysate solutions were tested within three intestinal sections from the bluefin tuna. The everted intestinal fractions immersed in the hydrolysate solutions were sampled at different times to analyse for AA and absorption rate calculations. Fresh sardine and SMH contained greater amounts of essential amino acids (EAA) than those of non‐essential amino acids (NEAA); however, the profiles of AA absorbed showed higher absorption of NEAA in both cases. Using a similar concentration solution, the absorption rates within the intestinal fractions showed a preferential absorption in the proximal and distal regions for Arg and His when FSH was used. However, the absorption rates for Lys resulted in a decreasing proximal‐to‐distal gradient between the different intestinal regions for FSH and SMH. The possibility of a catabolic role of certain AAs in the enterocytes being able to explain the differences in absorption is discussed.     

Gustatory responses in Pacific bluefin tuna Thunnus orientalis (Temminck and Schlegel)

Gustatory neural responses of the Pacific bluefin tuna Thunnus orientalis (Temminck and Schlegel) to extracted compounds of prey organisms, such as amino acids, nucleotide‐related substances, organic acids and organic bases, were electrophysiologically recorded from the facial nerve supplying the anterior palate. Of the 17 amino acids tested, l ‐proline was the most potent amino acid at 10^?2 M, and its threshold was the lowest at around 10^?6 M. l ‐leucine, l ‐methionine, l ‐alanine, l ‐valine and l ‐isoleucine were also highly stimulatory at 10^?2 M; however, the other 11 amino acids examined were not as effective or were ineffective. Thus, the gustatory receptors for amino acids of the Pacific bluefin tuna show a narrowly tuned response profile. Among the seven nucleotide‐related substances tested, uridine‐5′‐monophosphate, inosine‐5′‐monophosphate and adenosine‐5′‐diphosphate were highly stimulatory, and their thresholds were 10^?4–10^?5 M. Inosine elicited a positive response at 10^?2 M but its response magnitude was not so high. Organic acids l ‐lactic and pyruvic acids were effective at 10^?2 M, but no response was elicited at 10^?3 M. Among organic bases, betaine was highly stimulatory, and its response magnitude at 10^?2 M is almost equal to that of l ‐proline at the same concentration. The threshold for betaine was determined to be at around 10^?5 M. Trimethylamine oxide and ammonium chloride were ineffective.     

Effect of taurine enrichment in rotifer (Brachionus sp.) on growth of larvae of Pacific bluefin tuna Thunnus orientalis (Temminck & Schlegel) and yellowfin tuna T. albacares (Temminck & Schlegel)

To investigate the dietary effect of taurine on the larval stage of tuna species, Pacific bluefin tuna (PBF) and yellowfin tuna (YFT), larvae were reared until 16 days after hatching (dAH) and 14 dAH, respectively, and replicate samples were fed either non‐taurine‐enriched rotifers (T‐0) or rotifers enriched with 800 mg taurine L^?1 (T‐800). Most PBF and YFT larvae were at the preflexion stage until 7 and 8 dAH, and there were no differences in the growth performance and total protein content of larvae between the T‐0 and T‐800 groups (t‐test; P > 0.05). Thereafter, however, for larvae of both species, these parameters in the T‐800 group significantly increased with enhanced notochord development compared to those in T‐0 group (t‐test; P < 0.05). Except for the RNA content in PBF larvae, there were no significant differences in changes of DNA and RNA content with larval growth between the T‐0 and T‐800 groups, but both PBF and YFT larvae showed increased protein DNA^?1 and protein RNA^?1 ratios in the T‐800 group compared to the T‐0 group after notochord flexion. This indicates that taurine is an important nutrient for the rapid growth of early stage PBF and YFT larvae, and we conclude that the growth improvement of PBF and YFT larvae by dietary taurine supplementation is due to the increase in protein synthesis efficiency after notochord flexion.     

Fatty Acid Composition of U.S. West Coast Albacore Tuna (Thunnus alalunga) and the Effects of Canning and Short-Term Storage

ABSTRACT

Changes in the fatty acid composition of 13 bled and blast-frozen U.S. West Coast albacore tuna (Thunnus alalunga) were determined following custom-canning and 5 weeks of canned storage. In accordance with typical custom-canning procedures, no additional packing materials were used, and the product did not undergo a precooking step. Raw albacore tuna was found to be rich in n-3 polyunsaturated fatty acids (PUFAs), with an average of 9.1% (% wt of total fatty acids) EPA and 33.8% DHA. Canning and short-term storage did not cause major fluctuations in the fatty acid profiles of the albacore tuna, with no significant changes in the total fractions of saturated fatty acids (30–31%), monounsaturated fatty acids (19%), PUFAs (50%), or n-3 PUFAs (46–47%). On a tissue weight basis, U.S. West Coast albacore tuna was found to contain high levels of total n-3 PUFAs, with 3.3 g/100 g tissue in raw tuna and 4.0–4.1 g/100 g tissue in products that were canned and stored for 5 weeks.     

南海黄鳍金枪鱼(Thunnus albacores)摄食习性及其随生长发育的变化及其随生长发育的变化

基于2012-2013年在我国南海水域调查获得的黄鳍金枪鱼(Thunnus albacores)生物学基础性数据,利用传统胃含物分析方法并结合碳、氮稳定同位素技术对黄鳍金枪鱼摄食习性进行了研究.结果显示,南海黄鳍金枪鱼食物组成包括鸢乌贼(Sthenoteuth is oualaniensis)、枪乌贼属(Uroteuthis)、乌贼属(Sepia)、圆鲹属(Decapterus)、蛇鲭属(Gempylus)、帆蜥鱼(Alepisaurus ferox)、日本乌鲂(Bramajaponica)、燕鳐属(Cypselurus)、甲壳类动物及不可辨别鱼类等饵料类群,其中,鸢乌贼(IRI=51.07％)、圆鲹属(IRI=39.81％)及不可辨别鱼类(IRI=6.62％)为主要饵料食物.黄鳍金枪鱼的空胃率、平均饱满指数和食物组成都有明显的月变化(P＜0.05).空胃率随叉长组变化呈较明显的上升趋势,各叉长组之间空胃率变化显著(P＜0.05);平均饱满指数随叉长变化较大.当叉长组为130-160 cm时,Shannon-Weiner多样性指数H在0.50-1.18之间变化,Pielou均匀度指数J在0.10-0.32之间.基于氮稳定同位素计算的黄鳍金枪鱼各叉长组的平均营养级为3.54.     

Characterization and Cryoprotection of Invasive Silver Carp (Hypophthalmicthys molitrix) Protein Hydrolysates

ABSTRACT

Silver carp (Hypophthalmicthys molitrix) is regarded as an invasive, underutilized freshwater fish causing environmental and economic complications along the U.S. Mississippi River System. In this study, silver carp protein hydrolysates (FPH) were obtained from 30, 60, 90, 120, and 240 min hydrolysis with Protamex®. Amino acid composition showed polar amino acids, including Asp and Glu, and freed hydrophobic residues in FPH-90 and FPH-240. Protein surface hydrophobicity of FPH increased with increasing degree of hydrolysis. Cryoprotection was evaluated using a muscle (mince) food system with 6% FPH (w/w) from each hydrolysis time condition, an untreated mince (CTRL), and 8% (w/w) 1:1 sucrose-sorbitol (SUSO), respectively. After six freeze-thaw cycles (D7), all FPH treatments had lower (p < 0.05) expressible moisture, indicating strong water-holding capacity by the FPH. FPH formulations also imparted antifreeze activity equal to or better than SUSO, with the FPH-90 exhibiting higher (p < 0.05) proportion (43.9%) of unfrozen water at D7. Results from this study provide preliminary evidence for development of effective cryoprotectants using an underutilized, invasive fish species that can be exploited for environmental and economic gain in the form of value-added ingredients and further provide opportunities to understand the fundamental physicochemical properties governing cryoprotection of FPH in a frozen mince system.     

Production of Interesting Peptide Fractions by Enzymatic Hydrolysis of Tuna Dark Muscle By-Product Using Alcalase

ABSTRACT

A protein hydrolysate was prepared from proteins of tuna dark muscle by-product. The hydrolysis conditions (time, temperature, pH, and enzyme concentration) using Alcalase was optimized by response surface methodology (RSM). The regression coefficient close to 1.0, observed during experimental and validation runs, indicated the validity of the model. The hydrolysate produced under the optimum conditions determined by RSM has a low rate of peptide fraction of molecular weight of 4–1 kDa. Meanwhile, the results obtained by hydrolysis under optimal conditions determined by a complementary study (temperature 55°C, time 60 min, 1% enzyme concentration, and pH 8.5) show that the hydrolysate produced has a height rate of the peptide fraction of molecular weight of 4–1 kDa. The amino acid composition of the protein hydrolysate prepared proved to have the potential for application as an ingredient in balanced fish diets and as a source of nitrogen in microbial growth media.     

不同规格野生黄鳍金枪鱼肌肉营养分析与评价

探究不同规格黄鳍金枪鱼(Thunnus albacares)肌肉营养成分及品质差异,实验以野捕的 3种规格黄鳍金枪鱼J1 (4.2±1.2) kg、J2 (22.5±2.5) kg和J3 (50.8±3.9) kg为研究对象,通过常规生化分析方法对金枪鱼肌肉的常规营养成分、氨基酸、脂肪酸及矿物质元素进行比较分析。结果显示,(1) J1组水分含量显著高于J2、J3组;J2、J3组粗蛋白含量显著高于J1组(P<0.05);J3组粗脂肪含量显著高于J1、J2组(P<0.05)。(2)检出19种常见氨基酸,氨基酸含量最高的为谷氨酸(3.04~ 3.25 g/100 g),必需氨基酸中含量最高的为赖氨酸(2.02~2.15 g/100 g),最低的为色氨酸(0.31~ 0.45 g/100 g)。非必需氨基酸含量J3>J2>J1 (P<0.05);必需氨基酸、呈味氨基酸含量J1组显著低于J3组(P<0.05)。依据氨基酸评分(AAS),缬氨酸为第一限制性氨基酸;以化学评分(CS)为评分标准,J1、J2组第一限制性氨基酸为色氨酸,J3组为苯丙氨酸+酪氨酸。(3)各组共检出25种脂肪酸,以多不饱和脂肪酸(PUFA)为主,含量最高的为二十二碳六烯酸(DHA),占总脂肪酸含量的37.46%~39.18%。DHA含量J3组显著高于J1、J2组;二十碳五烯酸(EPA)含量J2、J3组显著高于J1组;DHA∶EPA比值J1组显著高于J2、J3组(P<0.05)。单不饱和脂肪酸(MUFA)含量J3>J2>J1;PUFA含量J3组显著高于J1、J2组(P<0.05)。PUFA/饱和脂肪酸(SFA)、n-3系多不饱和脂肪酸/n-6系多不饱和脂肪酸(n-3/n-6)比值J2、J3组显著高于J1组(P<0.05)。h/H比值J3组显著高于J1、J2组(P<0.05)。(4) J2、J3组Na、Ca含量显著高于J1组,J1组K含量最高且显著高于J2、J3组(P<0.05)。4种重金属元素均低于食品中建议的最大允许限量,其中Fe含量最大的为J3组,且J3>J2>J1 (P<0.05);Cu含量最大的为J3组,且显著高于J1组(P<0.05)。综合分析,大规格黄鳍金枪鱼具有更好的营养质量,本研究为居民膳食的选择及黄鳍金枪鱼人工配合饲料的配制提供了科学依据。     

Effects of Brief Summer or Winter Fasting on the Muscle Quality of Cultured Pacific Bluefin Tuna (Thunnus orientalis)

The effects of fasting on the quality of the dorsal and ventral ordinary muscles from cultured Pacific bluefin tuna (Thunnus orientalis) during chilled storage were investigated. Tuna were subjected to fasting for 2 days in the summer or 6 days in the winter prior to harvesting. The breaking strength of the dorsal ordinary muscle sampled in the summer increased until 24 h and then decreased. There were no significant differences in the lipid and glycogen content of the ordinary muscle after 9 h of storage between the controls and either fasting group. The pH of the ordinary muscle subjected to summer and winter fasting was higher than in the controls after 24–48 h of storage. However, the relationship between the pH and glycogen content was unclear. The metmyoglobin content during chilled storage was lower in the ordinary muscles from either fasting group than in the controls. In conclusion, fasting for 6 days in the winter improved the color stability of the ordinary muscle without a decline in its lipid content.     

Movements,behavior, and habitat utilization of yellowfin tuna (Thunnus albacares) in waters surrounding the Revillagigedo Islands Archipelago Biosphere Reserve,Mexico

The movements, behavior, and habitat utilization of yellowfin tuna, Thunnus albacares, following capture and release with archival tags in the Revillagigedo Islands Archipelago Biosphere Reserve (RIABR), Mexico, are described from analyses of 16 578 days of time‐series data, downloaded from 52 archival tags recovered from yellowfin (78–173 cm in length and 1.7–8.0 yr of age) at liberty from 93 to 1773 days ( = 411 days), collected during 2006–2012. An unscented Kalman filter model with sea‐surface temperature measurements integrated (UKFsst) was used to process the archival tag data sets to obtain improved estimates of geographic positions, most probable tracks (MPTs), and movement parameters. The MPTs indicate restricted movements, low levels of dispersion, and fidelity of yellowfin tuna to the RIABR. The median parameter estimates from the UKFsst model for errors in longitude (σ_x) and latitude (σ_y) were 0.46° and 1.84°, respectively, for directed movements (u and v) –0.05 NM day^?1 and –0.05 NM day^?1, respectively, and for dispersive movement (D) 117.99 NM² day^?1. Analyses of daily timed depth and temperature records resulted in the classification of the data into four distinct behaviors. There are significant differences among ages in the durations of Type I and Type II diving behaviors and in the daytime and nighttime vertical habitat utilization distributions. The oceanography surrounding the RIABR appears to have a profound influence on the movements, behavior, and habitat utilization of yellowfin in this area.     

Preparation and Characterization of Protein Hydrolysates From Little Loligo Squid (Uroteuthis chinensis)

Research on the little loligo squid (Uroteuthis chinensis) protein hydrolyzed by papain and Flavourzyme and characterization of hydrolysates was carried out in this article. The optimum hydrolysis conditions of papain were obtained by orthogonal experiments, and the influence factors on the degree of hydrolysis such as enzyme/substrate ratio, hydrolysis time, pH, and temperature were investigated. The effect of Flavourzyme on the degree of hydrolysis was also studied. The characteristics of freeze-dried hydrolysates such as yield, moisture, nitrogen recovery, molecular mass distribution, and amino acid composition were determined. The results showed that papain and Flavourzyme could hydrolyze the little loligo squid protein efficiently, and the degree of hydrolysis was up to 25.82% under the optimum hydrolysis conditions. The average molecular mass of hydrolysates obtained with papain and Flavourzyme was 1,246 Da, and the low molecular mass peptides were the main fraction of hydrolysates. The yield, moisture, and nitrogen recovery of freeze-dried hydrolysates was 19.8, 4.4, and 74.2%, respectively. Compared with suggested patterns of amino acid requirements by the Food and Agriculture Organization of the United Nations/World Health Organization (FAO/WHO), the hydrolysates of the little loligo squid had high nutritional value, and was a potential nutritious supplement used in various food products.     

Proximate and Fatty Acid Compositions in Different Flesh Cuts of Cultured,Cultured Fasted,and Wild Pacific Bluefin Tuna (Thunnus orientalis)

This study was carried out to determine the differences in proximate and fatty acid (FA) compositions in different flesh cuts of the most valuable cephalic portion of cultured (full-cycle), cultured fasted (full-cycle), and wild Pacific bluefin tuna (PBT; Thunnus orientalis). Cultured fasted PBTs were fasted for 6 days to ensure empty stomachs during harvesting and to determine the influence of fasting on the lipid and FA composition in different flesh cuts. Significantly higher lipid contents were observed (p < 0.05) in the dorsal akami (lean part) and the ventral o-toro (very fatty part) flesh cuts in cultured and cultured fasted PBTs than in wild ones. However, monounsaturated fatty acid (MUFA) contents in all flesh cuts were significantly higher in cultured and cultured fasted PBTs than in wild PBT. Wild PBTs contained significantly higher (p < 0.05) polyunsaturated fatty acid (PUFA) contents than other cultured PBTs in all flesh cuts except for the dorsal akami and wakaremi (fatty part near dorsal fin) flesh parts, and contained higher n-3 FA content than other PBTs—especially docosahexaenoic acid (DHA, C22:6n-3)—in the lipid fraction from the dorsal chu-toro (medium fatty part), ventral akami, ventral chu-toro, o-toro, and in dark flesh cuts. The flesh quality of cultured or cultured fasted PBTs has the advantage of having a higher total amount of essential FAs than that of wild PBT.