Microbiological and Physicochemical Quality of Carp sausage Enriched With Propolis Natural Extract during Chilled Storage

This study aimed to determine the effect of propolis extract on quality of liquid smoked carp (Cyprinus carpio) sausage stored at 2°C for 9 weeks. Carp sausages were separated into three groups: control group, without propolis extract; second group, with 1% (w/w) propolis extract added; and third group, with 2% (w/w) propolis extract added. Propolis extract added carp sausages showed lower total volatile basic nitrogen (TVB-N) value, peroxide value (PV), and free fatty acid (FFA) content compared to control during the storage period. During 9 weeks of storage, propolis extract added carp sausages showed significantly lower total aerobic mesophilic bacteria (TAMB) and psychrophilic bacteria count (PBC) than those of control samples (p < .05). Yeast and mold were not detected in all fish sausages throughout the storage period.     

Shelf-Life of Spanish Mackerel (Scomberomorus commerson) from Northern Australian Waters

Abstract

The shelf-life of Spanish mackerel caught by line fishing in Northern Australian waters was evaluated. Spiked fish were stored in ice either headed and gutted or left uncut and subjected to sensory, nucleotide, pH, histamine and microbial analysts and the rigor pattern recorded. There was little difference between the two product forms. Rigor in uncut fish lasted for 14 ± 9.8 hours and in headed and gutted fish for 19.6 ± 16.3 hours. Spanish mackerel retained good sensory quality for up to 14 days. The bacterial load reached 105 cfu/g by 18 days. K values were low for most of the storage time, < 40%. Histamine levels did not develop more than 10 mg/kg during storage. The pH of Spanish mackerel did not change much even though bacterial levels become high.     

Effect of Traditional and Liquid Smoke on the Quality of Sea Catfish Sausages (Sciades herzbergii,Bloch, 1794)

ABSTRACT

Smoking is a technique used to improve the sensory attributes and increase the shelf life of fish. The objective of the present study was to evaluate the nutritional, physicochemical, microbiological, and sensory characteristics of sausages made with sea catfish (Sciades herzbergii) fillets subjected to the traditional and liquid smoking processes. The traditionally smoked sausages showed lower (p < .05) moisture content and higher protein, fat, and mineral levels, higher weight loss during processing, higher pH, higher a* (red intensity), and lower L* (luminosity) values. The percentage of shrinkage, water holding capacity, water activity, hardness, cohesiveness, and elasticity were not influenced (p > .05) by the smoking methods tested. The microbial counts of both treatments were in compliance with the current Brazilian legislation. The sensory acceptance of the liquid smoked sausages was higher (p < .05) when compared to the traditionally smoked sausages for the attributes of color, aroma, texture, flavor, and overall acceptance, with scores ranging from 6 (liked slightly) to 7 (liked moderately). Between the two smoking methods tested, liquid smoking presented better sensory acceptance, easier execution, greater process control, and less environmental impact; thus, it is a viable alternative to the traditional smoking of sea catfish (Sciades herzbergii) sausages.     

Quality and Shelf Life Assessment of Puffer Fish (Lagocephalus guentheri) Fillets during Chilled Storage

The aim of the study was to quantify the shelf life and quality characteristics of puffer fish, Lagocephalus guentheri, fillets on chilled storage at 2 ± 1°C. The puffer fish muscle contains 16.14% protein, 80.76% moisture, 0.99% ash, and 0.17% fat. The mouse bioassay proved the absence of tetradotoxin in muscle, liver, skin, and gonads of the fish. The polyunsaturated fatty acid to saturated fatty acid (P/S) ratio of puffer fish was found to be 1.3, with n-3 to n-6 ratio of 3.27. The puffer fish had hypocholesterolemic/hypercholesterolemic ratio (H/H) value of 2.68, artherogenicity index of 0.43, and thrombogenicity index of 0.29. Beheaded and deskinned fishes were filleted and were studied for 10 days of chilled storage. The physical, chemical, sensory, and microbiological parameters showed significant (p < 0.05) changes during the entire storage period. While the hydrolytic rancidity was significantly correlated to springiness, gumminess, and chewiness of fillets, the peroxide value (PV) correlated with the color attributes and pH. The hardness of the samples decreased significantly and was evident in both sensory and instrumental analysis. With storage time, the yellowness of the fillets increased steadily. The results of this study can help in improving processing, preservation, and marketing aspects and enhance the utility of puffer fish.     

琼胶寡糖及EGCG对冰藏花鲈鱼片新鲜度与蛋白质生化特性的影响

花鲈贮运期间易受微生物与内源酶的联合作用,导致新鲜度及蛋白质生化特性改变,影响其食用价值。因此,采用适当的保鲜方式对花鲈贮运流通过程中的品质变化加以调控,以保证其品质安全显得尤为重要。为探究表没食子儿茶素没食子酸酯(EGCG)及琼胶寡糖(AO)对冰藏花鲈鱼片的保鲜效果,对硬度值、色差及新鲜度指标(硫代巴比妥酸值、K值、挥发性盐基氮、菌落总数、感官评分)进行测定,并对蛋白质生化特性(肌原纤维蛋白含量、二级结构、巯基、羰基含量)进行分析。结果显示,对照组在第16天时感官得分低于8,且菌落总数和K值已分别高达(6.78±0.15) lg(CFU/g)与67.37%±1.75%,不可食用,而EGCG组(EG)、琼胶寡糖组(AO)及复合组的样品仍具有较好的硬度、色泽及新鲜度。贮藏至20 d时对照组的TBA值高达(0.81±0.03) mg/kg,而EG组、AO组及复合组的TBA值在贮藏期间均未出现大幅度增加,且始终低于对照组。另外,贮藏至12 d时对照组的羰基含量已显著高于其他保鲜处理组,对照组在贮藏末期的羰基含量上升至(1.63±0.04)nmol/mg,而EG组、 AO组及复合组的羰基含量仅为(1.14±0.03)、(1.28±0.08)与(0.99±0.09) nmol/mg。贮藏末期复合组的蛋白含量、α螺旋、巯基均高于对照组和单一保鲜组。研究表明,EGCG及琼胶寡糖均能较好地维持鱼片的新鲜度,能显著抑制蛋白质变性与氧化,且二者复合后的保鲜效果优于单一保鲜剂,延长鱼片保质期至20 d以上。该研究为EGCG及琼胶寡糖的保鲜机理提供了理论基础,为开发高效的新型生物保鲜剂提供参考。     

The Effects of Natural Antioxidant Extract Isolated from Giant Red Shrimp (Aristaeomorpha foliacea) Shells on Fatty Acid Profiles of Anchovy (Engraulis encrasicolus) During Refrigerated Storage

The aim of the present study was to determine the effects of natural antioxidant extract isolated from the shells of giant red shrimp (Aristaeomorpha foliacea) on the changes in fatty acid profile of anchovy (Engraulis encrasicolus) during refrigerated storage (2.7°C). Total antioxidant activity of shell extract was determined as 45.84%, total phenolic compound as 17.87 mg/100 g shell, and total carotenoid content in shell as 20.31 mg/100 g shell. Total saturated fatty acid (SFA), monounsaturated fatty acid (MUFA), and polyunsaturated fatty acid (PUFA) contents in the control group and the group with 0.1% shell extract addition were found to be affected by the duration of storage (p < 0.05). A percentage increase was determined in MUFA content, while decreases were observed in PUFA content. No statistically significant change was detected in SFA, MUFA, and PUFA contents of groups with added butylated hydroxytoluene (BHT) and 0.5% of shell extract (p > 0.05). It was concluded that the extract isolated from shrimp shells could be used during the cold storage of fish fillets instead of synthetic antioxidants.     

真空包装淡腌青鱼品质和细菌类型及数量

在零售市场和生产企业抽取4批真空包装淡腌青鱼,对其感官、化学和细菌学品质特性进行分析,并对细菌类型和数量进行研究。结果显示,产品栅栏因子及强度存在差异,盐分含量6.68%~12.06%,平均值(9.36±2.2)%;水分活度值0.75~0.91,平均值0.82±0.07;pH值6.00~6.30,平均值6.20±0.13。栅栏因子种类和强度的不同决定产品品质的差异,感官评价均可接受,过氧化值均值为19.65±8.75 meq/kg,挥发性盐基氮均值为24.50±15.30 mg/100 g,菌落总数均值为4.45±1.15 cfu/g,大肠菌群均低于30 MPN/100 g。从4批淡腌青鱼样品分离到234株细菌,73.9%是革兰氏阳性细菌,其中36.3%是葡萄球菌,31.6%是链球菌,并出现少量微球菌和棒状杆菌;由需氧革兰氏阴性杆菌不动杆菌、摩氏杆菌和鞘氨醇单胞菌组成较小的细菌菌群约占总细菌群落的18.4%,显示水分活度、盐分含量和pH值等栅栏因子与产品细菌类型和数量呈一定相关性。     

养殖大黄鱼加工和冰藏过程中鲜度和细菌类型的变化

通过对养殖海水以及捕获、加工、流通和冰藏等整个供应链过程养殖大黄鱼的温度履历、感官、化学、微生物的品质监测,评估养殖海水、碎冰和加工过程中大黄鱼细菌卫生状况,分析其在整个过程鲜度和细菌相变化。结果表明,养殖海水和碎冰的菌落总数分别为4.99±0.41 lg cfu/g和3.90±0.32 lg cfu/g,大肠菌群数分别为30~450 MNP/100 g和低于30 MNP/100 g;新捕获养殖大黄鱼的菌落总数为3.82±0.38 lg cfu/g,假单胞菌数为3.13±0.58 lg cfu/g,嗜冷菌数为2.82±0.60 lg cfu/g,大肠菌群数为低于30 MPN/100 g;冰藏第18天时TVBN含量为28.62±0.51 mg/100 g,菌落总数、假单胞菌数、嗜冷菌数和大肠菌群数分别为6.24±0.06lg cfu/g、6.01±0.25 lg cfu/g、5.68±0.21 lg cfu/g和30 MPN/100 g。养殖海水和新捕获鱼中细菌种类繁多,革兰氏阴性菌分别占其总菌株数的64.9%和56.8%;革兰氏阳性菌分别占其总菌株数的27.0%和42.0%;优势菌群为黏性威克斯菌、腐败希瓦氏菌和假单胞菌属。加工结束后,假单胞菌(34.9%)、玫瑰小球菌(32.6%)和缺陷短波单胞菌(14.0%)成为主要菌群。冰藏第4天时仅分离出4种不同类型的细菌,腐败希瓦氏菌比例上升明显,冰藏第10天和第18天时,所占比例分别为63.5%和69.1%,是冷却链养殖大黄鱼产品的优势腐败菌。     

花鲈冰藏过程中肌原纤维蛋白生化特性与新鲜度变化的相关性

为研究冰藏期间花鲈鱼片的品质及蛋白质生化特性的变化,通过感官评分、pH、质构、色差、硫代巴比妥酸值(TBA值)、挥发性盐基氮(TVB-N)值、菌落总数(TVC)和肌原纤维蛋白含量、巯基、羰基含量的测定及十二烷基硫酸钠—聚丙烯酰胺凝胶电泳(SDS-PAGE)确定了冰藏花鲈鱼片理化指标变化,并对肌原纤维蛋白生化特性与主要的...     

Properties of Fish Sausages Containing Common Carp (Cyprinus carpio) Roe Oil and Defatted Roe Protein Hydrolysate during Refrigerated Storage

Influence of emulsified or non-emulsified common carp roe oil (CRO) and carp defatted roe hydrolysate (CDRH) on properties of crucian carp (Carassius auratus) sausages was determined during 30-day storage at 4°C. Sausages containing CRO and CDRH were lighter and had better textural properties including hardness, gumminess, and chewiness. These textural attributes were significantly higher in the sample prepared with pre-emulsified CRO and 7 g/100 g CDRH (p < 0.05). The sausages fortified with CDRH also presented better microstructure, as evidenced by fewer voids and smaller oil droplets. When incorporated at 7 g/100 g, CDRH could significantly reduce microbial spoilage in sausages in terms of the total viable count and the psychrophilic bacterial count (p < 0.05); however, pre-emulsification had no significant effect on antibacterial activity of hydrolysate in the samples (p > 0.05). Sausages with pre-emulsified roe oil and 7 g/100 g hydrolysate were more resistant against lipid oxidation and had a higher level of polyunsaturated fatty acids, especially docosahexaenoic acid and eicosapentaenoic acid after 30 days of storage at 4°C. Furthermore, the sausages with pre-emulsified CRO and 7 g/100 g CDRH exhibited better organoleptic properties at day 30.     

鲤鱼冷藏中的鲜度变化与货架期

以感官、化学和微生物为指标,研究了养殖鲤鱼在0℃(冰藏)、5℃、10℃和15℃贮藏过程中的鲜度变化和货架期,并对菌落总数、嗜冷菌、假单胞菌、挥发性盐基氮与感官评价的一致性程度进行了探讨。结果表明,在0℃、5℃、10℃、15℃的贮藏过程中,鲤鱼的高品质期分别为426 h、189 h、95 h和58 h,货架期分别为713 h、382 h、146 h和87 h。各温度高品质期终点和货架期终点时菌落总数分别为6.63±0.45 lg cfu/g、7.18±0.29 lg cfu/g,假单胞菌数分别为5.69±0.75 lg cfu/g、6.50±0.33 lg cfu/g,挥发性盐基氮均值分别为9.90±0.52 mg/100 g、20.52±0.34 mg/100 g。各温度下高品质期终点和货架期终点时各指标均值均无显著差异(P0.05),表明菌落总数、假单胞菌和挥发性盐基氮作为鲤鱼低温贮藏的鲜度指标与感官鲜度评价有较好的一致性。     

Impact of Dietary Oil Source on the Shelf-Life of Gilthead Seabream (Sparus aurata)

Gilthead seabream were fed two diets containing 100% fish oil (FO) or a 75% vegetable oil blend (VO) (50/50 soybean and rapeseed oil) in order to study the effect on shelf life. The fish were stored at 4 ± 1ºC for 0, 7, 14, and 21 days. Physicochemical, microbiological, and sensory analyses were performed. The fatty acid composition of muscle reflected the profile of dietary lipids. A smaller quantity of highly unsaturated fatty acids (HUFAs) in the VO group resulted in lower lipid oxidation. In this group, lower thiobarbituric acid reactive substances (TBARS) values were observed during the storage and an increase in saturated fatty acid (SFAs) occurred later than in the group FO. Higher water holding capacity (WHC) of muscle was also observed in the VO group. A higher redness (a* value) was observed in the VO group, although discoloration occurred with the same intensity in both groups. Despite the differences among groups observed in psychrophilic and Pseudomonas counts and in some sensory attributes, shelf-life was equal for both groups.     

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.     

Effects of Handling Methods on Quality Changes of Giant Freshwater Prawns (Macrobrachium rosenbergii)

Abstract

Prawns (Macrobrachium rosenbergii) were subjected to conditions, which simulated domestic and export handling practices. Prawns were mixed with crushed ice to maintain the prawn samples temperature at 0°C and were stored at room temperature (25 ±2°C) for 48 hr for the domestic handling trial, while for export handling, the samples were kept in a cold room at (0 ±1°C) for 72 hr. Both processes showed sensory, chemical and instrumental changes but the magnitude of the changes for domestic handling was greater than for those of the export trial. Maximum load (firmness), energy to the breaking point (chewiness) and percent of cooking loss increased as storage time increased up to 12 hr, after which prolonged storage resulted in a decrease in these parameters in the cooked samples. Expressible juice decreased during the first 12 hr, later increased gradually. Other chemical parameters such as the soluble-insoluble collagen ratio, proteolysis index (PI) and total volatile nitrogen (TVN) of cooked prawn increased with the increase in storage time. Good correlations among instrumental, chemical and sensory evaluation results were obtained for texture and taste-odor attributes of samples from both of the handling trials. Blanching and deheading of the prawns were found to maintain qualities very well, while samples, which underwent proper handling procedures, exhibited some quality changes after 48 hr.     

Effect of Thermal Microbial Inactivation and Washing on Quality Properties of Fish Sausage During Cold Storage (4°C)

The effect of microbial inactivation and washing process on physicochemical and sensory quality of pasteurized fish sausage during cold storage (4°C) was evaluated. Mince was obtained after the grinding; washed mince (WM) was obtained by single washing of mince; and surimi was obtained after three washing and dewatering cycles. Texture profile analysis results demonstrated that textural characteristics of pasteurized fish sausages remain stable during storage period (p > 0.05). Color analysis showed that Hunter L* had an increasing trend, and a* and b* had a decreasing trend over time (p < 0.05). Thus, it is possible to inactivate all microorganisms in pasteurized fish sausage without any undesirable effect on physicochemical and sensory quality.     

Quality preservation of salted,vacuum packaged and refrigerated mahi sefid (Rutilus frisii kutum) fillets using an onion (Allium cepa) extract

The combined effect of light salting, vacuum packaging and onion extract on the shelf life of mahi sefid (Rutilus frisii kutum) fillets under refrigeration was assessed using chemical, microbiological and sensory methods. The shelf life of control, air‐packaged, salted (APS), vacuum‐packaged, salted (VPS) and vacuum‐packaged, salted with onion extract (VPSOE) samples was determined to be up to 6, 9, 15 and 18 days respectively. The values of total volatile basic nitrogen, free fatty acid and thiobarbituric acid increased progressively during the storage period for all the treatments. However, the preservative methods applied led to an extended shelf life of fillets based on chemical indices and sensory attributes in the following order: VPSOE>VPS>APS>control group. The assay of the total viable count (TVC) revealed that 2% and 4%VPSOE produced a decrease in TVC throughout the storage period. According to the results obtained, the best method to preserve the mahi sefid fillet was by 4%VPSOE treatment.     

Effects of Partial and Complete Replacement of Synthetic Cryoprotectant with Carrot (Daucus carota) Concentrated Protein on Stability of Frozen Surimi

ABSTRACT

The study aimed to evaluate the effects of carrot concentrated protein (CCP) as additive on the functional and textural properties of surimi from striped catfish (Pangasianodon hypophthalmus) during six months of frozen storage (?20°C). The CCP (82.22% crude protein) was used as an additive either a lone or with a synthetic cryoprotectant (sucrose-sorbitol-sodium tri-polyphosphate). Control was made with synthetic cryoprotectant only. Molecular weight of CCP was found to be 36 kDa. After six months, the results revealed that up to 50% of synthetic cryoprotectants could be replaced by CCP during frozen storage of surimi. Biochemical parameters such as protein solubility, Ca²⁺ATPase activity, and gel strength decreased significantly (p < .05) during storage. Treatment T-3 (CCP 0.5% + 50% of synthetic cryoprotectant) maintained quality of protein significantly superior (p < .05) in respect to denaturation and other functional and sensory attributes compared to all the treatments. The microstructure images of surimi confirmed that addition of CCP modified the ice crystal growth during frozen storage. This study suggests that CCP can be a potential additive to protect protein from denaturation along with partial replacement of chemical cryoprotectants.     

Biochemical,Physical, Chemical,and Microbiological Assessment of Blue Shrimp (Litopenaeus stylirostris) Stored in Ice

Postmortem changes in blue shrimp (Litopenaeus stylirostris) muscle were studied on the basis of biochemical, chemical, physical, and microbiological changes during an 18 day storage period at 0°C. Adenosine 5′-triphosphate (ATP) content, breakdown products, K-value, pH, trimethylamine nitrogen (TMA-N), total volatile basic nitrogen (TVB-N), water holding capacity (WHC), color, and texture (shear force) changes were examined. Also, total mesophilic and psychrophilic bacterial counts were measured. K-value increased linearly (r² = 0.98) from an initial value of 1.37 ± 0.59 to 59.42 ± 6.05% at Day 18. Spoilage indicators TVB-N and TMA-N increased from 29.56 ± 1.33 and 0.69 ± 0.25 to 39.04 and 2.04 ± 0.59 mg of N/100 g at Day 18, respectively; meanwhile, the total viable counts of mesophilic and psychrophilic bacteria increased from 3.48 ± 0.44 and 2.61 ± 0.29 log CFU/g to 6.27 ± 0.21 and 7.14 ± 0.39 log CFU/g, respectively, which indicated spoilage at the end of the storage period. The pH, texture, WHC, and color were affected (p < 0.05) during the storage period. Overall, results indicate that blue shrimp muscle quality was maintained for 12 days of storage in ice.     

Changes in Biochemical Compositions and Quality of White Shrimp (Litopenaeus vannamei) During Storage

ABSTRACT

To understand biochemical characteristics, storage stability, and freshness indicators of white shrimp (Litopenaeus vannamei), changes in extractable nitrogenous compounds, microbial count, and sensory rating of white shrimp during storage at 25 and 4°C were investigated. Free amino acids showed a slow increase during storage at 25°C, but no obvious change was found at 4°C. Adenosine triphosphate (ATP) and adenosine diphosphate (ADP) were found at initial stage and decreased rapidly after storage. Both inosine 5′-monophosphate (IMP) and adenosine monophosphate (AMP) increased and then decreased during storage. Inosine, hypoxanthine, and the K-value gradually increased with time. The levels of total volatile basic nitrogen (TVB-N), NH₃, and trimethylamine (TMA) of white shrimp increased with storage time at 25 and 4°C. The TVB-N, NH₃, TMA, inosine, hypoxanthine, and K-value could be considered as freshness indicators of white shrimp during storage. However, the total plate count did not corroborate the acceptability recommended limits for white shrimp during storage. The sensory evaluation, associated with TVB-N, TMA, and K-value, showed the quality was unacceptable after 6 h storage at 25°C and 7 days at 4°C.     

大黄鱼冷藏过程肌肉蛋白质生化特性与新鲜度的相关性

为研究大黄鱼冷藏期间肌肉蛋白质变化与鲜度品质的相关性,以色差值、质构、挥发性盐基氮(TVB-N)以及感官评分等鲜度指标判断鱼肉品质,并结合肌肉蛋白质中盐溶性和水溶性蛋白质含量、总巯基含量、羰基含量、蛋白质分子量以及粒径分布等蛋白质生化特性指标,分析大黄鱼4℃冷藏10 d肌肉蛋白质变化与鲜度品质的相关性。结果显示,冷藏期间大黄鱼肌肉的L*、a*和W值下降,b*值上升;鱼肉咀嚼性、黏着性和硬度下降;TVB-N由(4.42±0.21) mg/100 g增至(38.46±0.87) mg/100 g,并于第8天达二级鲜度标准,感官评分第8天不可接受。冷藏期间大黄鱼盐溶性和水溶性蛋白质含量、总巯基含量、羰基含量变化趋势相似。盐溶性蛋白质含量呈先小幅上升后下降的变化趋势,由(159.36±6.51) mg/g降至(91.99±13.82) mg/g,质量分数下降了42.27%,水溶性蛋白质含量由(33.68±2.13) mg/g降至(17.57±0.70) mg/g,质量分数下降了47.77%。盐溶性蛋白质的巯基含量和羰基含量分别由(3.95±0.04) mol/105g pro降至(1.08±0...