Analysis and Evaluation of Nutritional Composition of Farmed Male Pufferfish (Takifugu obscurus) Liya WANG 1, Ningping TAO 2 College of Food Science & Technology Shanghai Ocean University Shanghai, China 1.E-mail：[email protected] 2.E-mail: [email protected] Abstract: The nutritional composition of the main tissues(meat, testes and liver) of farmed Takifugu obscures were investigated. All tissues reported in this study showed higher contents of crude protein in meat (18.44±0.11 g/100g) and testes(17.15±0.15 g/100g), lower contents in liver (3.89±0.16g/100g ). At the same time, liver (63.86±0.93 g/100g) contain higher contents of crude fat, testes (1.82±0.13 g/100g) and meat(1.31 ±0.21 g/100g) contain lower crude fat contents. Concerning the minerals, amounts of the macroelement K were the highest elements in meat, testes and liver. Zn were the most abundant microelement in meat and testes; Fe were the most abundant microelement in liver. In addition, amino acids (AA) were rich in testes and meat. The contents of total AA (TAA) in meat and testes were 80.08 ±0.75g/100g and 63.33±0.10 g/100g, respectively. The ratios of total essential AA (TEAA) to TAA in meat and testes were 40.60% and 39.33%, respectively. The TEAA/TAA were comparable to the reference values recommended by FAO/WHO. The AA contents of meat were dominated by glutamic acid, testes were dominated by arginine. According to amino acid score (AAS), the first limiting acid of meat was tryptophan; the first limiting acid of testes were (phenylalanine+ tyrosine). Key words: farmed pufferfish; meat; testes; liver; compenent;nutritional evaluation Compared with the general fish, puffer fish meat is 1. Introduction high in protein, low fat, and rich in essential amino Puffer fish, also name bubble fish, warm water acids, minerals. In addition to meat, sexual gland also marine benthic fish. Generalized puffer fish include rich in nutritional value, testis are rich in protamine, all species of the dolphin-shaped mesh, but in fact DNA, Zn and Se, and had good name of “beauties puffer means a class of highly toxic but delicious milk” in the history . Currently, the study reported on economic fish which closely related to our food, the nutritional value of the puffer fish’s testes and culture and history. China is the production and liver is not yet complete. This article analyze and marketing power of puffer fish in the world. The evaluate farmed Takifugu obscurus’ nutritional and annual allowable catch is more than 100,000 tons, quality of testes and liver tissue, in order to provide a accounting for about 70% of the world's total output, theoretical basis of effectively development and and its 70% to 80% for export, mainly to Japan, South utilization the resources of farmed Takifugu obscurus. [1] Korea . In recent years, China has made significant 2. Material and Methods progress in puffer fish farming industry. Farmed fugu fish is mainly based on the produce poison mechanism, 2.1 Material the growth of ecological and physiological Takifugu obscurus collected from the breeding requirements, by using a series of core technology base of Jiangsu Ocean Group Co., Ltd. in April 2010, such as artificial breeding, control toxic and healthy [2] taken 8 male samples which are all 2 ages old, farming, to control its poison in food range . In gonadal maturation, uniform size, weight (328±36)g which farming Takifugu obscurus fish is unique and body length(20±1)g. After conventional biological Chinese migration of fish. Its individual large, measurements, quickly slaughtered, try removing fast-growing, fresh meat, nutrient-rich, are popular [3] other debris attached to the organization, such as with consumers. Yin Ning confirmed that under the glands, fat, connective tissue, blood clots and dirt, condition of freshwater aquaculture with bait gives, then washed clean, the liver weight (43±14)g, testis supplemented by certain technical measures, even if weight for (20±7)g. After homogenate, the fish Takifugu obscurus reach sexual maturity, their ovarian packing in zip lock bag, the liver and the testis are sub and liver are non-toxic. Professor Hua Yuanyu, puffer package in thread mouth bottle, quick freeze under- fish farming expert in Nanjing Normal University who think Fugu obscurus after generations of nurturing by 80 ℃stand-by. fully freshwater environments, can produce toxic 2.2 Determination of Nutrients generation low than the generation, and safe to eat "[4]. 14 Nutrients are determined with reference to the (FAO/World Health Organization (WHO)) in 1991 [9]. relevant standard. The water is referencing to AOAC, The amino acid score (AAS), essential amino acid 2007, methods 950.46; crude protein reference to index (EAAI), the branched chain amino acids/ the AOAC, 2007, method 981.10; crude fat reference to Aromatic value amino acids (TBCAA,/TArAA) AOAC, 2007, method 948.22; ash with reference to Calculated as follows: AOAC, 2007, method 938.08[5]. Amino acid is AAS（%）= Test protein amino acid content (g/100g referencing Adeyeye[6] etc, hydrolysis by 6mol/L protein)/FAO scoring model amino acid content (g/100g hydrochloric acid, assay by Japan's Hitachi L-8800 protein)×100 amino acid automatic analyzer. Because tryptophan is n 100ab 100 100h destroyed in hydrochloric acid hydrolysis, so EAAI referencing to the determination of Wu Fang etc. ae b e h e [7] .Using 5mol/L NaOH which containing 0.5% Wherein: the n is comparing the number of soluble starch solution hydrolysis, plus essential amino acids; the a, b, c, ..., h are essential KH2PO4-NaOH buffer, measured by Shimadzu amino acids content of test protein (g/100g protein); ae, RF-5301pc fluorescence spectrophotometer. b , c , ..., h are essential amino acids content of egg [8] e e e Referencing the determination of to Borges et al , proteins, (g/100g protein). measured constants and trace elements K, Na, Ca, Mg, Zn, Fe, Cu by TAS-990 flame atomic absorption 2.4 Statistical Approach spectrophotometer of Beijing Purkinje General Using SPSS13.0 software on variance analysis Instrument Co., Ltd. Se being determinate by PE what measured data of general nutrients and elemental ELAN60000 model ICP-MS of Beijing Bode analysis, ±S.D is statistical results, P <0.05 is HengYue Electronics Co., Ltd.. P measured by significant difference. UV-1100 spectrophotometer that produced by Beauty Spectrum of Instrument Co., Ltd., Shanghai, China. 3. Results and Discussion 2.3 Evaluation Method of Nutritional Quality 3.1 General Nutrition Composition Analyses Nutritional quality evaluation based on the amino acid score mode proposed by the FAO/WHO Table.1 Proximate composition in the tissues of farmed Takifugu obscures (g/100g, wet, mean±S.D., n=3) Tissues Moisture Crude Protein Crude Fat Ash Content Meat 79.73±0.52a 18.44±0.11a 1.31±0.21b 1.42±0.04b Testes 79.53±0.90a 17.15±0.15b 1.82±0.13b 2.22±0.08a Liver 29.81±0.23b 3.89±0.16c 63.86±0.93a 0.64±0.02c The different letters in same column mean statistically significant difference (P < 0.05) Table. 2 Amino acids composition and content in the tissues of farmed Takifugu obscurus（%,dry,mean±SD.,n = 3） Amino Acid Meat Testes Liver Amino Acid Meat Testes Liver Asp** 5.92±0.05 a 4.39±0.01b 0.42±0.02c Lys* 7.79±0.06 a 7.19±0.02 b 0.42±0.03c Thr* 3.78±0.05 a 3.01±0.03 b 0.27±0.02c His 1.99±0.03 a 1.17±0.00 b 0.15±0.01c Ser 3.61±0.05 3.14±0.02 0.30±0.02a Arg** 5.64±0.06 b 8.63±0.01 a 0.39±0.03c Glu** 11.97±0.18 a 5.99±0.03 b 0.69±0.04c Pro 3.69±0.19 a 2.92±0.09 b 0.29±0.02c Gly** 5.38±0.04 5.92±0.08 0.52±0.06a Trp* 0.54±0.02 b 1.06±0.02 a 0.14±0.01c Ala** 4.86±0.05 a 4.27±0.01 b 0.35±0.02c TAA 80.08±0.75 a 63.33±0.10 b 5.66±0.66c Cys 1.82±0.01 a 1.19±0.01 b 0.15±0.00c EAA 32.51±0.30 a 24.91±0.10 b 2.21±0.12c Val*c 4.12±0.03 a 3.05±0.01 b 0.30±0.01c UAA 47.57±0.52 a 38.42±0.11 b 3.45±0.21c Met* 3.24±0.04 a 2.07±0.01 b 0.21±0.01c NEAA 33.72±0.06 a 29.21±0.07 b 2.36±0.15c Ile*c 3.48±0.11 a 2.20±0.01 b 0.18±0.01c TEAA/TAA 40.60 39.33 39.05 Leu*c 6.80±0.05 a 4.35±0.01 b 0.45±0.03c TEAA/TNEAA 68.34 62.21 64.06 Tyrd 2.74±0.04 a 1.75±0.05 b 0.20±0.01c TUAA/TAA 42.11 46.12 41.76 Phe*d 2.76±0.05 a 1.99±0.01b 0.23±0.02c The different letters in same column mean statistically significant difference (P < 0.05) TAA: total amino acids; * TEAA: total essential amino acids; TNEAA: total nonessential amino acids;** TUAA: total umami amino acids; 15 The nutritional composition of the meat, testes and about 40%, TEAA / TNEAA is 60%.