Effect of ice storage on the functional properties of pink perch and oil sardine meat

Ice storage of dressed pink perch (Nemipterus japonicus) and Indian oil sardine (Sardinella longiceps) for 16 and 20 days, respectively, resulted in a decrease in emulsifying capacity (EC), protein solubility (PS), relative viscosity (RV) of salt‐soluble proteins (SSP) and water‐soluble proteins (WSP), water binding capacity (WBC) in terms of absorbed moisture in water (AM_w), absorbed moisture in brine lpar;AM_b), retained moisture in water (RM_w) and retained moisture in brine (RM_b), WSP and SSP, and increase in cook loss (CL). Decrease in protein solubility influenced the EC, RV, CL and WBC in both the species of fish. Significant (P<0.05) correlations existed among various functional properties analysed, in both the fishes during the ice storage. © 1999 Society of Chemical Industry     

Effect of freezing time on the quality of Indian mackerel (Rastrelliger kanagurta) during frozen storage

The present study aims to find the effect of freezing methods on the quality of mackerel (Rastrelliger kanagurta) in commercial plate and air blast freezers during freezing and subsequent frozen storage (-18 degrees C). Total time for freezing was significantly different (P < 0.05) between the plate and air blast freezers (90 and 220 min, respectively). This difference in the freezing time could be attributed to the varied quality of the 2 samples. Upon freezing, the moisture content decreased in air blast frozen samples compared to plate freezer where protein content decreased in both the samples. Upon freezing and during frozen storage, lipid oxidation products (peroxide value, thiobarbutiric acid value, and free fatty acid value) and volatile bases (total volatile base nitrogen and trimethyl amine nitrogen) showed an increasing trend in both the samples with values slightly higher in air blast frozen samples compared to plate frozen samples. The total plate counts showed a significantly (P < 0.05) decreasing trend in both the samples. K value did not show any significant (P < 0.05) difference between the samples where as the histamine formation was significantly (P < 0.05) increased in air blast frozen samples compared to plate frozen samples. The taste and overall acceptability was significantly different (P < 0.05) in plate frozen samples compared to air blast frozen samples on 3rd month. Both samples were in acceptable condition up to 3 mo but the plate frozen samples quality was slightly better than the air blast frozen samples.     

Influence of feeding state and frozen storage temperature on the lipid stability of Atlantic mackerel (Scomber scombrus)

Lipid deterioration of mackerel caught in Icelandic waters was studied, as affected by different frozen storage temperatures (?18 °C vs. ?25 °C) and seasonal variation (August vs. September). The lipid stability was investigated by analyses of hydroperoxide value (PV), thiobarbituric acid reactive substances (TBARS), free fatty acids, as well as changes in fatty acid composition. Results showed significant lipid deterioration with extended storage time, where the lower storage temperature showed significantly more protective effects. Furthermore, a higher lipid oxidation level was recorded for fish caught in September than in August, although lipid hydrolysis occurred to be greater for fish in August than in September. Moreover, results indicated a rather stable level of omega‐3 fatty acid during the whole frozen storage period. The analysis indicated that both lipid oxidation and hydrolysis were affected by the frozen storage temperature and the stability differed with regard to season of catch.     

The effect of frozen storage of mackerel (Scomber scombrus) on its quality when hot-smoked

Whole mackerel (Scomber scombrus) were frozen using a horizontal plate freezer, wrapped in plastic bags and frozen stored at - 20°C. At suitable intervals (11, 22 and 33 weeks) the fish were removed from the cold store and subsequently hot smoked (in gutted from) using an AFOS-Torry Mini Kiln. All smoked mackerel samples, despite their different previous histories, were assessed by the panellists as moderately acceptable products in- terms of their texture and flavour, even after 33 weeks frozen storage prior to smoking. Protein denaturation, as related to salt-soluble protein, was influenced by the frozen storage history (24% drop after 33 weeks frozen storage) and seemed to be affected by the free amino acids formed during frozen storage. After smoking the denaturation was extensive (above 80%) in all mackerel samples. Lipid oxidation was quite extensive (PV 108 meq kg^?1) in the 22 and 33 weeks frozen stored mackerel samples. However, no rancid flavour in the latter smoked mackerel samples was detected by taste panellists. A 58% increase in free amino acids during frozen storage was observed. Extensive losses of 74% in available lysine were observed in the 22 and 33 weeks frozen stored mackerel samples after smoking which could be due to aminocarbonyl reactions with the products of lipid oxidation. A 40% loss of thiamine was observed in the 33 weeks frozen stored samples after smoking. The histamine contents did not exceed 94 mg kg^?1 and would not be expected to cause symptoms of scombrotoxin poisoning.     

The effects of freeze-drying and storage on the FT-Raman spectra of Atlantic mackerel (Scomber scombrus) and horse mackerel (Trachurus trachurus)

FT-Raman spectroscopy was undertaken for quantitative characterization of lipids in horse mackerel (Trachurus Trachurus) and Atlantic mackerel (Scomber scombrus). Peroxide value of fish lipids and protein extractability of the fish lipids and muscles were also measured by titration and Bradford assay, respectively.     

Use of kiam wood extract as gel enhancer for mackerel (Rastrelliger kanagurta) surimi

Kiam ( Cotylelobium lanceotatum craih) wood was extracted using water or ethanol. Water kiam wood extract (WKWE) and ethanolic kiam wood extract (EKWE) contained tannin at levels of 251.90 and 456.30 mg g⁻¹ of dry extract, respectively. Effects of WKWE and EKWE at different levels (0–0.60% of protein content) on the properties of gels from mackerel ( Rastrelliger kanagurta ) surimi were investigated in comparison with commercial tannin (CT). Gels added with 0.30% WKWE, 0.15% EKWE or 0.30% CT had the increases in breaking force by 134.81%, 136.09% and 121.34% and in deformation by 52.60%, 54.96% and 33.53%, respectively, compared with the control (without addition of extracts or CT). The lowered expressible moisture content and the formation of cross-linked myosin heavy chain were also observed in surimi gels incorporated with those additives. Thus, the extract of kiam wood can be used as surimi gel enhancer without affecting its sensory properties.     

不同解冻方式对智利竹筴鱼船上冻品贮藏品质的影响

以挥发性盐基氮（TVB-N）、三甲胺氮（TMA-N）、组胺以及硫代巴比妥酸（TBA）含量为指标,研究了不同解冻方式对智利竹筴鱼在-18℃下冻藏6个月品质的变化。结果表明,流水解冻相对于室温解冻和4℃解冻,在TBA和组胺含量上有显著性差异（p<0.05）,而室温解冻和4℃解冻在TVB-N,TMA-N,TBA和组胺上组间差异不显著（p>0.05）。结果表明,4℃解冻对于鱼体品质变化的控制较为理想。      

Chemical and nutritional quality of Indonesian dried-salted mackerel (Rastrelliger kanagurta)

Indonesian mackerel ( Rastrelliger kanagurta ) were sun dried or salted and sun dried and stored at 30°C for up to 20 weeks in air. During processing and storage polyunsaturated fatty acids oxidized to form thiobarbituric acid (TBA) reactive substances and fluorescent compounds. TBA values increased with increasing salt content (range 2.3–20.7%). Positive, highly significant correlations were found between the odour of the stored products and both fluorescent pigment production and the degree of browning. Amino acid analysis indicated loss of lysine, glutamic acid, serine, histidine, arginine and the sulphur containing amino acids, but these losses were far too small to account for the massive decreases found in net protein utilization (NPU) of the stored products, measured by rat-feeding trials. The latter were highly correlated with the fluorescent pigment content and degree of browning in products of intermediate (∼ 14%) salt content.     

The effect of different salting procedures and qualities of raw material on some nutrients during processing and storage of salted-dried mackerel

Salted-dried mackerel ( Scomber scombrus ) was prepared using fresh fish or fish which had been stored in ice for 75h and four methods of salting, namely 15% brine, saturated brine, pickle and dry salting. Samples were analysed for available lysine, thiamine and riboflavin before salting, after salting, after drying and after 1 month's storage at 20°C. Final losses of each of these nutrients were lowest when the fish were pickle cured. Losses were also lower when fresher raw material was used. the use of good quality fish and a pickle salting method is therefore recommended for this type of product.     

Preliminary development of intermediate moisture,pasteurised mackerel (scomber japonicus marplantensis) chunks

The objective of this study was to develop an intermediate moisture, pasteurised mackerel product combining the lowering of water activity (a_w) by means of selected solutes with pasteurisation. Loss of water was achieved by soaking in an equilibrium solution containing glycerol, salt, and potassium sorbate. An optimum cooking time of 20 min in the infusion solution and an optimum immersion time of 20 h in the same solution were determined. A final a_w value of 0.89 was obtained. These parameters were selected taking into account the sensory assessment, since the main problem in this kind of food is acceptance by the consumer. The product was pasteurised at 90°C for 40 min. The product obtained by this combination of conditions had a moderately sweet taste and a succulent texture.     

Effect of season on heavy metal contents and chemical compositions of chub mackerel (Scomber japonicus) muscle

Seasonal variations of heavy metals concentrations and overall chemical compositions were determined in chub mackerel caught in the Southern Sea of Korea. The average mercury and lead content varied between 0.04 and 0.08 mg/kg and between 0.01 and 0.02 mg/kg, respectively. Seasonal variations were not detected in lead, but mercury displayed maximal values in winter (P < 0.05). A distinct seasonal pattern was found in crude fat content with maximal values in December and minimal values in April. Fatty acid composition showed that monounsaturated fatty acids levels were the highest in August, while polyunsaturated fatty acids (PUFA) levels were the highest in April. The major contributing factors to the seasonal variation of PUFA amounted to 20:5n-3 and 22:6n-3. The total amino acids content varied from 180.6 to 187.7 mg/g. There were no significant seasonal variations in total amounts of amino acids. Practical Application: Mackerel (Scomber japonicus) is one of the most important fishing resources in Korea. The effects of polyunsaturated fatty acids (PUFA) on the human body have been identified, and consequently, the intake of fish lipids has steadily increased among the human population. There have been few studies on safety and alterations in chemical composition of mackerel attributed to seasonal fluctuations. Therefore, the results presented in this study could be used to improve the safety and nutrition information available to consumers.     

柠檬醛纳米乳液对鲅鱼鱼糜凝胶品质及贮藏稳定性的影响

目的 为了改善鱼糜制品的品质及其贮藏稳定性,添加不同浓度柠檬醛纳米乳液（0.35%-0.55%,添加量为3%）制备鲅鱼鱼糜。方法 测定鱼糜的凝胶性能、微观结构、挥发性盐基氮（total volatile basic nitrogen,TVB-N）值、氧化稳定性以及菌落总数。结果 柠檬醛纳米乳液的添加提高新鲜鲅鱼鱼糜的凝胶强度、持水性以及质构特性 (P < 0.05),降低蒸煮损失率 (P < 0.05),且凝胶网络结构致密有序,孔洞较小,表面光滑。当柠檬醛纳米乳液浓度为0.45%时,新鲜鱼糜凝胶品质最好。此外,在贮藏过程中,各处理组鱼糜的持水性、蒸煮损失、氧化稳定性、TVB-N值和菌落总数均优于对照组,表现最佳为0.45%组。结论 柠檬醛纳米乳液的加入能够提高鲅鱼鱼糜的凝胶性能,增强鱼糜在贮藏过程中的氧化稳定性,抑制鱼糜中微生物的生长,为进一步鱼糜凝胶品质的改善提供参考。     

真空预冷对芥蓝采后常温货架期品质的影响

以芥蓝(Brassica capitata)为实验材料,研究了采后真空预冷处理对芥蓝冷链物流运输后在常温货架期(25℃)品质的影响。通过测定相关指标,结果表明:采后真空预冷显著地降低了芥蓝在常温货架期间的失重率、黄化指数和相对电导率,延缓了叶片的叶绿素荧光参数(Fv/Fm)、可溶性固形物(TSS)、蛋白及V_C等含量的下降;至常温货架期第3 d,经过预冷的芥蓝,其失重率、黄化指数和相对电导率分别为未预冷的77%、73%和51%,而Fv/Fm、蛋白及V_C含量分别为未预冷的5.5、6.5和1.4倍。说明预冷能够较好地维持芥蓝在常温货架期间的品质。      

Effect of different thawing methods on the quality of mackerel (Pneumatophorus japonicus)

Food Science and Biotechnology - Five thawing methods such as flow water thawing, ultrasonic flowing water thawing, air thawing, microwave thawing and low temperature thawing were used, and the...     

不同贮藏温度下鲐鱼生物胺变化的研究

为探究不同温度和预处理对鲐鱼生物胺含量变化的影响,用高效液相色谱法分析了整鱼和去内脏鱼在不同贮藏温度下8种生物胺以及总生物胺含量的变化,结果发现,鲐鱼中主要的生物胺为组胺、腐胺、尸胺、酪胺。随着温度的升高,鲐鱼中总生物胺含量的增加迅速变快。在0、4、10、15、20、25和30 ℃贮藏1 d后,整鱼中总生物胺的积累量分别为40.34、93.44、107.95、73.39、119.99、4649.90、6446.43 mg/kg。在0、4、10、15、20、25和30 ℃贮藏条件下,整鱼中组胺的含量超过国家规定的高组胺鱼类安全限量(400 mg/kg)的时间分别为12、5、4 d和48、36、15、14~16 h,-18 ℃贮藏6个月,组胺积累量仅为13.45 mg/kg。另外,去内脏能减少生物胺的生成,在-18、0、4、10、15、20、25和30 ℃贮藏条件下,去内脏后总生物胺最终积累量减少程度分别为14.22%、39.79%、13.83%、29.06%、22.60%、13.56%、26.13%、21.26%。因此,低温冷冻和去内脏处理能够有效控制鲐鱼中生物胺的生成,防止腐败。本研究为有效控制鲐鱼生物胺的产生提供了参考依据。     

Effect of a flax seed (Linum usitatissimum) soaking treatment on the frozen storage stability of mackerel (Scomber scombrus) fillets

The effect of a flax seed (Linum usitatissimum) soaking on the development of rancidity in frozen mackerel (Scomber scombrus) was studied. Fresh mackerel fillets were soaked in an aqueous flax seed extract for 20 min and then kept frozen (?20 °C) for up to 7 months. A parallel experiment with non‐soaked fillets was carried out under the same conditions. The development of rancidity was measured by biochemical (free fatty acids, peroxides, conjugated dienes and trienes, secondary oxidation products, fluorescent and browning compounds and lipoxygenase activity) and sensory (general aspect, odour and colour) analyses. An inhibitory effect of the soaking treatment on rancidity development was observed according to the peroxide content and the formation of fluorescence and browning. A lower lipoxygenase activity was detected at 1 month in the soaked fillets; after this, no differences were obtained between either type of sample, whose activities at month 7 were negligible. According to the sensory analyses, non‐soaked fillets had fair quality at 1 month and were rejectable at 3 months, while the soaked ones were still of good quality at 1 month and rejectable at 5 months. According to the present results, soaking in an aqueous flax seed extract could be useful for inhibiting the development of rancidity in fatty fish fillets. Copyright © 2006 Society of Chemical Industry     

Effect of frozen-storage period on quality of American sirloin and mackerel (Scomber japonicus)

Food Science and Biotechnology - This study aimed to study the effect of frozen-storage period on the quality of sirloin and mackerel (Scomber japonicus). The samples were evaluated after being...     

Effect of pre‐treatment and smoking process (cold and hot) on chemical,microbiological and sensory quality of mackerel (Scomber scombrus)

The sensory, hygienic, toxicological and nutritional profiles of hot‐ and cold‐smoked mackerel samples were studied with various pre‐treatments. The panellists assessed all smoked samples as barely to quite acceptable products whilst the product immersed in 120 g kg^?1 sodium chloride and 60 g kg^?1 fructose prior to smoking was assessed as very acceptable regarding its sensory characteristics. The available lysine in all hot smoked samples was reduced to the same extent (32%) whilst a very good correlation (r = 0.912) was observed between loss of available lysine and colour formation of the cold‐smoked products, indicating the high contribution of lysine in the interactions with carbonyls. Histamine was found in highly unacceptable levels even in the unprocessed samples (600 mg kg^?1) and strongly increased (2220 and 2250 mg kg^?1) in the cold‐ and hot‐smoked samples, respectively, due to all treatments. These are levels which would be expected to cause symptoms of scombrotoxin poisoning. Benzo(a)pyrene, fluoranthene and perylene were at high levels both in cold‐ (2.1, 4.3 ± 0.04 and 7.2 ± 0.05 µg kg^?1) and hot‐smoked samples (9.2, 7.8 ± 0.03 and 9.4 ± 0.14 µg kg^?1, respectively) and were, as expected, influenced by the temperature. The aerobic bacteria remained at acceptable levels, since salt and high temperature prevent bacterial growth. Copyright © 2004 Society of Chemical Industry