冷藏和微冻条件下长丰鲢鱼片品质变化规律的研究

通过测定长丰鲢（ Changfeng silver carp ）鱼片在冷藏（4℃）和微冻（-3℃）条件下的感官品质、菌落总数（ TAC）、汁液流失率、 pH、电导率（ EC）、挥发性盐基氮（ TVB-N）以及K值等指标的变化，评价两种贮藏条件对长丰鲢鱼片品质的影响。结果表明：长丰鲢鱼片分别在4℃贮藏至第8天和-3℃贮藏至第25天时失去感官食用价值。4℃贮藏第6天菌落总数为6.75 lg cfu/g，-3℃贮藏第20天为5.89 lg cfu/g。 TVB-N值在4℃贮藏至第8天为29.1 mg/100 g，-3℃贮藏至第25天为21.1 mg/100 g。与冷藏相比，微冻贮藏下长丰鲢有较高的汁液流失率。综合各项指标变化，冷藏和微冻贮藏条件下长丰鲢鱼片的货架期分别为6 d和20 d，微冻贮藏较冷藏长丰鲢鱼片贮藏期延长了2.3倍。     

三种生物保鲜剂结合冷藏对菊黄东方鲀的保鲜效果

为了研究生物保鲜剂对菊黄东方鲀品质的影响,以菌落总数、挥发性盐基氮及汁液流失率为指标,探讨在4℃贮藏条件下,不同生物保鲜剂(茶多酚、乳酸链球菌素以及溶菌酶)处理对菊黄东方鲀品质的影响。结果表明,在贮藏10 d时,0.5%浓度茶多酚组的菌落总数为4.71 lg(CFU/g),TVB-N值为12.82 mg/100 g,汁液流失率为6.12%。在贮藏15 d时,0.2%浓度乳酸链球菌菌落总数仅为4.44 lg(CFU/g),TVB-N值为13.16 mg/100 g,汁液流失率为6.91%。在贮藏10 d时,0.3%浓度溶菌酶组的菌落总数为4.68 lg(CFU/g),TVB-N值为13.25 mg/100 g,汁液流失率为4.47%。空白组在贮藏10 d时的菌落总数达到5.52 lg(CFU/g),显著高于其他保鲜剂处理组(P0.05)。空白组汁液流失率显著低于保鲜剂组。结论:0.5%茶多酚、0.2%乳酸链球菌素及0.3%溶菌酶对菊黄东方鲀的保鲜效果均最佳。     

0 ℃冷藏条件下鲢阻抗特性与鲜度变化的相关性

为了更好地了解0 ℃冷藏条件下鲢（Hypophthalmichthys molitrix）鱼体的阻抗特性与鲜度的变化规律及相关性，建立鱼体鲜度快速检测方法，分别测定了鲢鱼片的品质指标[菌落总数、肌苷和次黄嘌呤浓度总和/ATP关联物浓度总和（K值）、汁液损失、感官评价]以及鲢鱼体的阻抗变化率（Q值），分析了Q值与各品质指标的相关性。结果显示，随贮藏时间的延长，鱼片的菌落总数、K值和汁液损失率逐渐增加，感官评分和鱼体的Q值逐渐减小。第15天鱼片的菌落总数为（6.85±0.07）log cfu·g-1，K值为（63.97±1.93）%，汁液损失率为（6.26±0.01）%，感官评分为10.0±1.4分，Q值为（22.92±2.60）%，此时鱼片失去食用价值。Q值与菌落总数、K值、汁液损失和感官评价的相关系数R分别为0.972、0.976、0.945和0.984（P〈0.01），表明Q值与各鲜度指标具有良好的相关性。在0 ℃贮藏条件下用Q值可快速、无损伤地评估鲢鲜度。     

低盐低糖处理鲟鱼片冷藏过程中品质变化规律

文章通过测定感官分值、菌落总数(TAC)、挥发性盐基氮(TVB-N)、ATP关联物、生物胺等指标,研究了低浓度盐和糖处理对鲟(Acipenser sinensis)鱼片4℃冷藏过程中品质变化的影响。结果显示,T1(1.8%食盐干腌)和T2(1.8%食盐+1.0%绵白糖干腌)组鱼片感官可接受时间均比空白组延长了5 d;空白组菌落总数第6天达到7.34 log CFU·g-1,而T1和T2组在第16和第12天分别达到6.76 log CFU·g-1和6.78 log CFU·g-1;空白组TVB-N的增长速率也显著高于T1和T2组(P0.05);和空白组相比,T1和T2组HxR的含量显著高于空白组(P0.05),但K值及ATP、AMP、IMP含量差异不显著(P0.05);腐胺、酪胺和精胺的含量随贮藏时间的延长升高,T1和T2组腐胺含量显著低于空白组(P0.05)。结果表明,盐和糖的加入,明显改善了鲟鱼片冷藏过程中的品质变化。     

贮藏过程中凡纳滨对虾生物胺的变化

以邻苯二甲醛(OPA)为柱后衍生化试剂,采用反相HPLC法测定凡纳滨对虾(Litopenaeus vannamei)中的酪胺(Tyr)、腐胺(Put)、尸胺(Cad)、组胺(His)、胍丁胺(Agm)、精胺(Spe)和亚精胺(Spd)等7种生物胺。结合虾的感官分析、pH值和T-VBN值测定等方法评价凡纳滨对虾的品质,分析了凡纳滨对虾在不同贮藏温度和贮藏时间下的生物胺种类及含量的变化。结果表明,在0和4℃两种贮藏温度下,尸胺和腐胺发生的变化均最显著,可以其作为凡纳滨对虾新鲜程度的参考指标,确定最长贮藏时间分别为8d和6d。     

鲤鱼片真空包装与盐腌处理在冷藏过程中的品质变化规律研究

为了科学地了解鲤鱼(Cyprinuscarpio)鱼片贮藏过程中的品质变化规律,帮助建立高效的品质控制技术,研究了鲤鱼片生鲜真空包装及1.5%盐腌普通包装在4℃冷藏条件下,挥发性盐基氮(TVB-N)、p H、电导率、汁液损失和K值的变化情况。结果显示,在整个贮藏过程中,TVB-N、电导率、汁液损失和K值均随贮藏时间的延长而上升。其中,真空包装生鲜鲤鱼片的TVB-N在贮藏过程中上升较缓慢,与生鲜鱼片相比,盐腌鱼片的TVB-N在贮藏过程中上升较慢,但汁液损失和电导率明显偏高;真空包装能有效抑制鱼片K值的上升,但盐腌无明显抑制效果;p H在贮藏过程中呈"V"形变化,贮藏后期真空包装和腌制处理均能抑制p H的升高。研究表明,鲤鱼片生鲜真空包装和1.5%盐腌普通包装在冷藏期间均能保持较好的鱼肉品质,具有良好的应用前景。     

液熏罗非鱼片在25℃贮藏过程中生物胺的变化

为考察液熏罗非鱼片在贮藏过程中生物胺的质量分数及其变化,鱼片采用真空和普通2种包装方式在25℃下贮藏,使用HPLC-紫外检测器分析腐胺（Put）、色胺（Try）、组胺（His）、苯乙胺（Phe）和亚精胺（Spd）5种生物胺的变化。结果表明,5种生物胺在30min内得到有效的分离,并且在0.25～10.0μg.mL-1质量浓度范围内呈良好的线性关系（R2〉0.999）,最低检测限0.02μg.mL-1,回收率73.8%～113.6%,相对标准偏差（RSD）低于10%。在真空包装和普通包装样品中,Put的最终质量分数为（13.94±0.66）和（16.25±0.16）mg·kg-1,His为（8.76±0.17）和（6.38±0.21）mg·kg-1,Spd为（0.85±0.17）和（0.95±0.21）mg.kg-1,而Try和Phe在贮藏全程未被检出。真空包装能明显延缓且抑制Put质量分数的增加,但对His和Spd无影响,且在2种包装的鱼片中检出的His均未超过国家标准。     

水溶性壳聚糖对鱼糜制品保鲜效果的影响

研究了添加不同质量分数的水溶性壳聚糖对鱼糜制品冷藏保鲜效果的影响。以感官评分、菌落总数、挥发性盐基氮（TVB-N）、硫代巴比妥酸（TBA）和pH为指标,考察鱼糜制品在4℃冷藏过程中的品质变化。结果表明,水溶性壳聚糖能够明显抑制细菌的生长与繁殖,阻止感官品质的下降,延缓TVB-N和TBA的上升。其中,添加2.0%的水溶性壳聚糖保鲜效果最佳,与空白组相比,能将鱼糜制品的冷藏保鲜期从9 d延长至13～14 d。     

不同贮藏温度下马鲛鱼和秋刀鱼中生物胺含量变化

建立反相高效液相色谱法快速检测鲭科鱼类(马鲛鱼和秋刀鱼)中8种生物胺(色胺、2-苯乙胺、腐胺、尸胺、组胺、酪胺、亚精胺和精胺)含量的方法,进而研究马鲛鱼和秋刀鱼在不同贮藏温度下(-30、4和25℃)生物胺含量的变化情况。衍生后的样品经反相色谱柱C18分离,以超纯水和甲醇为流动相梯度洗脱,254 nm紫外检测生物胺含量。结果显示,8种生物胺在17 min内完全分离,加标回收率为96.80%~116.29%,检出限、定量限分别为0.06~0.31mg/L和0.20~0.75 mg/L。马鲛鱼和秋刀鱼中总生物胺含量与贮藏温度和贮藏时间显著相关(P0.05),且随着温度(4、25℃)的升高而增加。-30℃条件下,在前10天秋刀鱼与马鲛鱼总生物胺含量均降低;10 d后秋刀鱼中总生物胺含量升高。两种鱼在3种不同贮藏温度下,2-苯乙胺、尸胺和组胺均是贮藏过程中的主要生物胺;在-30℃贮藏条件下,马鲛鱼2-苯乙胺和尸胺含量在前10天随贮藏时间延长而降低,而秋刀鱼中两者的含量在前10天逐渐增加;在4、25℃条件下,秋刀鱼较马鲛鱼更易产生组胺;鲭科鱼中精胺含量在整个检测时间内无明显变化规律。秋刀鱼在-30、4℃贮藏条件下未检出色胺和酪胺;马鲛鱼中色胺含量较低且变化不显著;鲭科鱼中酪胺在4℃贮藏条件下显著性升高。在25℃贮藏条件下,除亚精胺和精胺外,鲭科鱼中其他生物胺均明显增加。结果表明,鲭科鱼类中生物胺含量与贮藏温度紧密相关,低温贮藏可有效抑制鱼肉中色胺、2-苯乙胺、腐胺、尸胺、组胺和酪胺的产生。本结果可为鲭科鱼类贮藏和生物胺监控提供参考依据。     

宰前预冷处理对大口黑鲈冰藏品质的影响

为探讨活鱼宰前预冷对后期鱼片冷藏保鲜品质的影响,将鲜活大口黑鲈(Micropterus salmoides)置于不同温度(15℃、10℃、5℃)的水槽中暂养0.5 h后,宰杀并取鱼片冰藏,分析第0、第3、第6、第9、第12、第15、第18和第21天时的鱼肉感官、理化指标[pH、挥发性盐基氮(TVB-N)、鲜度指标(K值)、硫代巴比妥酸(TBA值)]及微生物[菌落总数(TVC)]变化情况,综合评价宰前预冷处理对大口黑鲈冰藏品质的影响。结果表明,15℃预冷处理可较好地保持大口黑鲈冰藏期间的品质,维持鱼肉感官品质,降低细菌的生长繁殖速度,延缓pH、TVB-N、K值、TBA值及菌落总数的上升,货架期较对照组延长约3 d。     

高效液相色谱法测定生物胺衍生条件的优化研究

利用荧光检测器（FLD）,采用柱前衍生高效液相色谱法（HPLC）对组胺（HIS）、色胺（TRP）、2-苯乙胺（2-PHE）、腐胺（PUT）、尸胺（CAD）、酪胺（TYR）、亚精胺（SPD）和精胺（SPM）8种生物胺（BA）进行测定分析。通过探究丹酰氯（Dns-Cl）质量浓度、反应体系的pH、衍生时间及衍生温度对生物胺衍生反应的影响,确定最优的衍生条件。结果显示,当Dns-Cl的质量浓度为BA质量浓度的10倍、pH 11.0、40℃下避光反应45 min,所有BA均能有效分离。BA的相对标准偏差（RSD）在3%以内,能够满足分析要求。     

Chemometrics Approaches to Monitoring of Biogenic Amines Changes in Three Fish Species

The biogenic amine contents in fillets of three freshwater fish of kutum (Rutilus frisii), common carp (Cyprinus carpio), and Caspian salmon (Salmon caspius) were monitored during storage at 4°C for 20 days. The amounts of biogenic amines were determined at regular intervals using high performance liquid chromatography after derivatization with benzoyl chloride. Significant differences in the levels of selected biogenic amines among the fish samples were found (p < 0.05) during storage times. While the amount of putrescine, cadaverine, histamine, and tyramine in the fish fillets increased during the storage time, the changes in spermine and spermidine contents of the fish species were minor and both showed low and inverse correlations with storage time. For each of the three fish species, the sensory acceptability limit was found to be 4–8 days. The quality and biogenic amine indices of fish samples showed high correlation with storage time (r > 0.9). The principal component analysis of the results indicated that the formation of biogenic amines displays a certain behavioral pattern in all fish samples.     

鳙在冷藏和微冻贮藏下品质变化规律的研究

文章研究了鳙（Aristichthys nobilis）在不同贮藏温度下的品质变化规律。将经过前处理的鳙分别贮藏在4℃和-3℃中，通过测定其感官和理化指标，即总挥发性盐基氮（TVB—N）、硫代巴比妥酸（TBA）、鲜度K值、pH、汁液流失率和蒸煮损失率，评价不同温度对鳙品质的影响。结果显示，鳙分别在4℃贮藏至第10天和-3℃贮藏至第30天时失去感官食用品质。但K值在4℃贮藏至第6天和-3℃贮藏至第20天超过临界值。4℃下鳙的TVB—N显著高于-3℃。在整个贮藏过程中TBA均未超过2．00mg·kg-1。的限量值，说明TBA不适合单独用于评价鳙的品质变化。pH分别在4℃贮藏至第4天和-3℃贮藏至第10天达到最低值，分别为6．81和6．76。与4℃相比，-3℃下鳙的汁液流失率和蒸煮损失率较高，这可能与-3℃微冻条件下鳙肉组织冰晶生成导致持水力下降有关。综合K值和感官指标的变化，4℃和-3℃下鳙的货架期分别为6d和20d，且-3℃贮藏能明显延长鳙的货架期。     

Formation of Biogenic Amines and Associated Biochemical and Microbial Attributes of Whole Sutchi Catfish (Pangasianodon hypophthalmus) during Iced Storage

Sutchi catfish (Pangasianodon hypophthalmus) is a highly preferred farmed species that is produced in huge quantities. Meat from ice-stored (4 ± 2°C) whole Sutchi catfish was evaluated for formation of biogenic amines, such as putrescine, cadaverine, histamine (HIM), agmatine, tyramine, spermine, and spermidine, and compared with biochemical, microbial, and sensory attributes during 22 days. Analysis of content of biogenic amines in the meat was carried out by liquid chromatography with tandem mass spectrometry using a without derivatization method. Three amines, namely, tyramine, spermidine, and spermine, were only present on 0^th day of storage. Presence of cadaverine was noticed from 9^th day onwards, where the aerobic plate count (APC) reached 4.85 log CFU/g. Putrescine was detected on the 22^nd day of storage, where the APC crossed 7 log CFU/g. HIM was detected in lower quantities from 3^rd day onwards. A shelf life of 15 days was determined based on sensory and microbiological evaluation. Although the samples were biochemically acceptable throughout the storage period, APC exceeded the limit on day 19, and the gradual increase of H₂S-producing bacteria, Brochothrix thermosphacta, Aeromonas, and Enterobacteriaceae, was observed during storage.     

带鱼腌制加工过程理化指标、微生物和生物胺的动态变化及相关性

为探明鱼类腌制过程生物胺形成机理,本文研究了带鱼(Trichiurus haumela)在腌制加工过程盐度、水分含量、水分活度(Aw)、pH、蛋白质水解指数(P.I.) 非蛋白氮(NPN) 、游离氨基酸、微生物和生物胺的动态变化及相互关系,结果表明：pH在腌制阶段增加但在干燥阶段下降；盐度、P.I和微生物(菌落总数、乳酸菌、葡萄球菌和微球菌)在整个加工过程持续上升,水分含量和Aw则持续下降。整个加工过程,发生了明显的蛋白质降解反应,NPN 和游离氨基酸在干燥阶段含量显著上升；总生物胺含量增加了2.26倍(p＜0.05),其中尸胺含量显著增加了157倍,其次是组胺。带鱼腌制过程,游离氨基酸与生物胺显著正相关(p＜0.05),作为生物胺前体物质对生物胺的形成影响较大,微生物则起到了促进和抑制生物胺的作用,生物胺的形成还受pH、盐度、Aw等因素的共同影响,是一个极其复杂的过程。     

The Effects of Fermentation Process with Acid and Lactic Acid Bacteria Strains on the Biogenic Amine Formation of Wet and Spray-Dried Fish Silages of Discards

The impacts of fermentation process with acid and lactic acid bacteria strains (Lactobacillus plantarum, Lactobacillus brevis, Pediococcus acidilactici, Enterococcus gallinarum, and Streptococcus spp.) on the biogenic amine formation of wet and spray-dried fish silage obtained from whole gibel carp (Carassius gibelio, freshwater discard), whole ponyfish (Equulites klunzingeri, seawater discard), and processing by-products of seabass (Dicentrarchus labrax) were investigated. The results showed that among biogenic amines, cadaverine, putrescine, spermidine, spermine, serotonin, dopamine, and agmatine were predominant in all groups. Significant differences (p < 0.05) in biogenic amine concentrations of wet and spray-dried fish silage were observed. Raw fish and wet silages contained histamine level lower than the allowable limit of 50mg/kg, indicating the use of raw fish material with low microbial counts. In addition, no histamine was detected in spray-dried fish silage, except for seabass by-products with a trace quantity of histamine (<0.04mg/100g). The starter culture used for silage preparation did not effectively retard formation of biogenic amines compared to acid silage. It can be concluded that there is potential use of fermented fish silage as a protein source and possibly as a probiotic ingredient for animal feed in both wet and dry form.     

The Effects of Chitosan Coating on Biogenic Amines Inhibition and Microbial Succession of Refrigerated Grass Carp (Ctenopharyngodon idellus) Fillets

Chitosan coating and plastic wrap coating were investigated for their effects on the quality of grass carp fillets stored at 4 ± 1ºC for a period of 20 days. The fillets were divided into groups of untreated (Control), wrapped with sterile preservative film (PE), and chitosan-treated (1, 2, and 2.5% w/v corresponding to CH1, CH2, and CH2.5, respectively). The final result demonstrated that chitosan coating has positive effects on the microbial inhibition of total volatile count (TVC), lactic acid bacteria (LAB), Enterobacteriaceae, Pseudomonas, H₂S-producing bacteria (including Shewanella putrefaciens), and Staphylococcus. With regard to the results of biogenic amines (BAs), putrescine (PUT) and histamine (HIS) were the major amines, and their concentration was significantly (p < 0.05) higher in Control and PE than in chitosan-coated fillets at the end of storage. The final concentration in Control, PE, CH1, CH2, and CH2.5 was 143.7, 160.1, 83.0, 59.4, and 44.2 mg/kg for PUT and 228.0, 57.1, 4.1 3.2, and 2.9 for HIS, respectively. Chitosan coating was found to inhibit the increase of total volatile base nitrogen (TVB-N), microbial population, and total BAs and prolong the shelf life of grass carp fillets. However, sterile plastic wrap coating had little positive effect on maintaining the quality of grass carp fillets during refrigerated storage.     

Physicochemical and Microbiological Changes During Drying of Wolf Herring (Chirocentrus dorab) and Coastal Trevally (Carangoides coeruleopinnatus)

The aim of the present study was to assess the physicochemical and microbiological changes during sun drying of salted wolf herring (Chirocentrus dorab) and coastal trevally (Carangoides coeruleopinnatus). For that purpose, the pH value, moisture, sodium chloride (NaCl) content, total volatile base nitrogen (TVB-N), histamine, cadaverine, putrescine, tryptamine, tyramine, spermine, and spermidine, as well as total aerobic mesophilic count, amine forming bacteria, total coliforms, Staphylococcus spp., and Bacillus spp., were determined. The initial pH value was 6.4 and increased during the salt drying process to 6.9 in both cases. The initial moisture, salt, and TVB-N levels of C. dorab and C. coeruleopinnatus were 64.3 and 60.3%, 2.55 and 2.70%, and 22.8 and 16.2 mg/100 g, respectively. At the end of drying, moisture decreased to 31.3 and 35.6%, respectively; salt increased to 13.71 and 16.04%; and TVB-N increased to 35.9 and 33.13 mg/100 g, respectively. Regarding total aerobic mesophilic count, amine forming bacteria, total coliforms, Staphylococcus spp., and Bacillus spp., a statistically significant (P < 0.05) reduction of the population was observed in both cases. Regarding the biogenic amine forming bacteria, Morganella morganii and Klebsiella pneumoniae were isolated from C. dorab; Bacillus cereus, Staphylococcus xylosus, and Providencia rettgeri were isolated from C. coeruleopinnatus. During sun drying, the amount of histamine, cadaverine, putrescine, and tryptamine was reduced; spermine was detected in C. dorab only during the first day, whereas spermidine was not detected. This reduction may be attributed to the presence of biogenic amine decomposing bacteria. However, further research is necessary in order to verify in situ this capacity and exploit potential applications for fish and fishery products.