Quality Of Rainbow Trout Fillets Research Articles

Oil-in-water emulsion loaded with optimized antioxidant blend improved the shelf-life of trout (Oncorhynchus mykiss) fillets: a study with simplex-centroid design.

This study aimed to obtain optimized mixture with three essential oils (EOs) for maximum antioxidant activity through the augmented simplex-centroid mixture design and evaluate the effect of this optimized blend on total aerobic psychrotrophic count (TAPC), lipid and protein oxidation, instrumental color parameters and texture profile in rainbow trout fillets at refrigerated storage for nine days. Considering the DPPH and FRAP assays, the ideal EO blend was 66% lemongrass and 34% oregano. During refrigerated storage, this blend at 2000ppm was equally effective as BHT (100ppm) (p > 0.05), mitigating the discoloration (a* and b*), lipid, and protein oxidation in 38.83%, 12.95%, 76.13%, and 35.13%, respectively, besides shows greater effectiveness for preserving texture changes (p < 0.05) and extending the shelf life in 13h. The lemongrass + oregano EO blend reveals a promising natural alternative to enhance the quality of rainbow trout fillets under refrigerated storage. Furthermore, the multiresponse optimization showed to be a strong ally in enabling the use of these EOs by food industries.

Effect of microencapsulated bitter orange peel extract in coatings based on quince seed mucilage on the quality of rainbow trout fillets

Effect of microencapsulated bitter orange peel extract in coatings based on quince seed mucilage on the quality of rainbow trout fillets

Effect of Chitosan Coating Impregnated with Thymoquinone and Eugenol on the Quality Parameters of Rainbow Trout (Onchoryncus mykiss) during Cold Storage (4ºC)

ABSTRACT This study aimed to evaluate the effect of chitosan coating impregnated with Thymoquinone (TQ) and Eugenol (EUG) on the quality of rainbow trout fillets during cold storage (4ºC). In-vitro and In-vivo techniques were used to evaluate biopreservative effects of chitosan coating containing TQ, EUG and their combination. In-vitro evaluation of chitosan (2%) solution containing TQ, EUG demonstrated antibacterial and antioxidant effects. In-vivo assays on coated rainbow trout fillet as a food model demonstrated that the growth of spoilage bacteria, lipid oxidation and formation of volatile nitrogen bases reduced significantly in treated samples during 12 days cold storage in comparison with control samples and the treated samples were consumable until the 12th day without adverse sensory changes (P <0.05). Chitosan coating containing TQ and EUG can be used as a high quality packaging material to increase the shelf life of various foods, including fish, seafood, meat and meat products.

Impact of gelatin nanogel coating containing thymol and nisin on the microbial quality of rainbow trout fillets and the inoculated Listeria monocytogenes

This study aimed to assess the effects of edible gelatin nanogel coating containing thymol and nisin on the inhibition of microbial flora and inoculated Listeria monocytogenes in fish fillets during a 12-day storage period at the temperature of 4°C. Data were collected and analysed on several factors of microbiological change, including total viable count, total psychrophilic count, lactic acid bacteria and hydrogen sulphide-producing bacteria count, and the inhibitory effects of the coating on inoculated Listeria monocytogenes were determined during 3-day intervals. The highest reduction rate of total viable bacteria (0.95 log CFU/g), total psychrophilic (0.92 log CFU/g), Hydrogen sulfide producing bacteria (0.66 log CFU/g), lactic acid bacteria (0.95 log CFU/g) and L. monocytogenes count (0.65 log CFU/g) were observed in gelatin nanogel containing thymol and nisin in comparison with control samples. Furthermore, the separate use of these compounds led to the significant growth inhibition of the bacteria compared with the control. Therefore, it was concluded that the gelatin nanogel coating without an antimicrobial agent could not be effective in bacterial growth control, and the added thymol and nisin would be beneficial in the preservation of foods such as fish and its products.

Application of Black Cumin and Green Tea Extracts and Oils for Microbiological, Physicochemical, Textural and Sensorial Quality of Vacuum Packaged Rainbow Trout Fillets Stored at 2±1°C

ABSTRACT The study was conducted to evaluate the effect of black cumin extract (BCD), green tea extract (GTD), black cumin oil (BCO), and green tea oil (GTO) (10%) on the proximate, microbial, physicochemical, textural, and sensorial quality of vacuum packaged rainbow trout during 16 days of storage at 2 ± 1°C. Results indicated that both BCD and BCO had significant effects on reduction of bacterial growth. Thiobarbituric acid (TBA) values (0.21–0.48 mg MA/kg) of all groups at the end of storage did not exceed the limit values. The BCD and BCO showed lower total volatile basic nitrogen (TVB-N) values than control, GTD, and GTO during storage, and TVB-N limit value was exceeded on the 11th day in the CO, GTD, and GTO, and on the 16th day in the BCD and BCO. During the research, pH and water activity of trout fillets ranged between 6.03–6.34 and 0.9863–0.9942, respectively. The results also showed that the BCD and BCO significantly improved the sensorial quality of the samples compared to CO, GTD, and GTO. Based on the results, the application of black cumin extract and oil was effective with at least a 5-day extension of shelf life in preserving the quality of rainbow trout fillets.

Chia musilage coating: Applications with gojiberry extract for shelf life extension of Oncorhynchus mykiss and it's antibacterial and oxidative effects

The present study was carried out to evaluate chia mucilage coating and goji berry extract as preservative agents in filleted trout during storage for 18 days at 4℃. The trout fillets were separated into four lots and applied the following treatments by immersion processing: I) Control (without coating), II) Chia (Ch), III) Chia + 1% Goji berry extract (Ch + 1GE), and IV) Chia + 2% Goji berry extract (Ch + 2GE), then stored for 18 days at 4°C. Results demonstrated that microbial growth was delayed in 2%GE containing chia coated group. In addition, the chia coated samples retarded the increase in the contents of TVB-N, pH, and TBA during storage. In addition, shelf life of the samples stored at 4ºC was determined as 3 days in control group, 15 days in groups of coated with Ch and Ch+1%GE and 18 days in group of coated with Ch+2% GE. Practical applications Quality of rainbow trout fillets was keeped by edible coating formed from chia seed musilage With the prepared coatings were inhibed oxidation and microbial growht during fillet storage. A high shelf life was determined by the coatings formulated with 1% gojiberry extract and 2% gojiberry extract. Chia musilage coating may be an alternative to other coatings in the coating of meat and meat products.

Protein-based halochromic electrospun nanosensor for monitoring trout fish freshness

In the present study, a protein-based halochromic nanosensor was designed to assess the quality of rainbow trout fillets. Zein nanofibers containing alizarin as the indicator dye were electrospun. The sensors were characterised using SEM, FT-IR, DSC, XRD, dye leaching, response time experiments and colorimetric analysis. TVB-N, TVC and pH of fish fillets were also measured over 12 days of storage at 4°C. FT-IR results showed that the alizarin was incorporated in the zein matrix by intermolecular hydrogen bonding. DSC graphs of zein based samples showed that the temperature of dehydration, glass transition and protein unfolding in the halochromic nanofibers were lower than in powdered zein. The amorphous structure of the zein samples was confirmed by XRD analysis. No color changes were occurred in the first 4 days of storage, but later, a light purple color could be observed in the sensor by the naked eye. The color of sensor became magenta by the 10th and 12th day of cold storage indicating spoilage. This fabricated halochromic nanosensor can monitor fish freshness in real time through color changes. The colorimetric results correlated well with microbial and chemical changes in the fish.

The function of nanoemulsion on preservation of rainbow trout fillet.

This study was conducted to investigate the effects of nanoemulsions prepared with various concentrations of olive oil on the sensory, chemical and microbiological quality of rainbow trout fillets. The results showed that the shelf life of rainbow trout fillets were determined as 10days for the control, 12days for tween 80 group, 14days for the 15% olive oil nanoemulsion group (O15) and 16days for both 30% (O30) and 45% olive oil nanoemulsion groups (O45). It was determined that the use of olive oil suppressed the fish smell and improved the organoleptic quality of fish fillets, extending shelf life. Best sensory results were obtained from O30 and O45 treatment groups. The use of nanoemulsion had a positive effect on the biochemical parameters (TVB-N, PV, FFA, TBARs and pH), as well as inhibiting bacterial growth compared to the control group. Among nanoemulsion groups, the lowest bacteria content was found in O45 group. As a result, O30 and O45 treatment groups can be recommended for the preservation of fish fillets.

Impact of glazing based on chitosan-gelatin incorporated with Persian lime (Citrus latifolia) peel essential oil on quality of rainbow trout fillets stored at superchilled condition

In this research, a new ice-glazing based on chitosan-gelatin (Ch-Gl) incorporated with Persian lime peel essential oil (LEO), and superchilled storage was established to assess the microbial, physicochemical, and sensory quality of rainbow trout fillets. The fillets were immersed in distilled water (control), Ch-Gl, Ch-Gl + 1% LEO, and Ch-Gl + 2% LEO to form glazing layer on the surface, then stored at −1.4 °C for 30 days. All treatments delayed the growth of total mesophilic bacteria, total psychrotrophic bacteria, Enterobacteriaceae, and lactic acid bacteria compared to control during the storage period. The treatments also retarded the increase in the contents of total volatile nitrogen, conjugated dienes, thiobarbituric acid reactive substances, protein carbonyls, pH, and electric conductivity during storage. The freshness indexes i.e. K and Fr values were improved in treated groups compared to control group. The combined treatments (Ch-Gl + 1% or 2% LEO) were more effective than Ch-Gl alone to inhibit the microbial growth, retard the physicochemical deterioration, and improve freshness indexes in the fillets. It can be concluded that ice-glazing based on Ch-Gl incorporated with LEO, and superchilled storage is effective to enhance the quality and shelf-life of rainbow trout fillets.

Chitosan Coatings Containing Mentha spicata Essential Oil and Zinc Oxide Nanoparticle for Shelf Life Extension of Rainbow Trout Fillets

ABSTRACT The objective of the current study was to determine the effects of chitosan (CH) coatings containing Mentha spicata essential oil (MSO; 0.2 and 0.4%) and zinc oxide nanoparticle (ZnO; 0.2 and 0.4%) on chemical (total volatile basic nitrogen (TVB-N), 2-thiobarbituric acid reactive substances (TBARS) and peroxide value (PV)), microbial (total viable count, psychrotrophic count, Pseudomonas spp., and Enterobacteriaceae) and sensory (odor, color, and overall acceptability) properties of raw rainbow trout fillets during 14 days of refrigerated storage. Final microbial population of CH + MSO 0.4% + ZnO 0.4% and CH + MSO 0.4% + ZnO 0.2% retarded approximately 3–5 log CFU/g as compared to control groups (P < 0.05). At the end of storage time in control samples, TVB-N, TBARS, and PV reached 49.3 mg N/100 g, 3.31 mg malonaldehyde/kg, and 2.04 meq peroxide/kg lipid, while the values for the treated samples with MSO (0.2 and 0.4%) in combination with ZnO (0.2 and 0.4%) remained lower than 25 mg N/100 g, 2 mg malonaldehyde/kg, and 1.1 meq peroxide/kg lipid, respectively. The results indicate a potential use of CH coating containing MSO and ZnO as an effective type of antimicrobial packaging to maintain quality of rainbow trout fillets.

Biogenic Amines and Predictive Models of Quality of Rainbow Trout (Oncorhynchus mykiss) Fillets during Storage

To estimate biogenic amines and changes in quality of rainbow trout ( Oncorhynchus mykiss ) fillets at different temperatures, we determined the sensory attributes, total volatile basic nitrogen (TVB-N), total viable counts (TVC), and biogenic amines (BAs) of samples that were untreated (CK) or dry cured with 1.8% salt (T). There was no significant difference between CK and T samples in terms of TVB-N, TVC, and BAs. TVB-N and TVC increased significantly (P < 0.05) with storage time at 3, 9, and 15°C. Putrescine (PUT) and cadaverine (CAD) increased significantly (P < 0.05) at -3, 3, 9, and 15°C during storage. Histamine formed more easily when storage temperatures were higher. The kinetic models of sensory scores for TVB-N, TVC, PUT, CAD, and the sum of PUT and CAD (PUT+CAD) in T samples versus storage time and temperature were developed based on the Arrhenius equation. High regression coefficients (R2 > 0.9) indicated the acceptability of the kinetic model for predicting changes in the quality of the rainbow trout fillets. Relative errors between predicted and experimental values of TVB-N, TVC, and PUT+CAD were all within 10% except for TVB-N on day 6. The prediction model based on TVB-N, TVC, and PUT+CAD can be applied to evaluate changes in quality of rainbow trout fillets from -3 to 15°C (270 to 288 K).

Quality assessment of rainbow trout (Oncorhynchus mykiss) fillets during super chilling and chilled storage.

In order to evaluate the effect of super chilling (-3°C) and chilled (3°C) storage on the quality of rainbow trout fillets, total volatile base nitrogen (TVB-N), drip loss, pH, electric conductivity (EC), total aerobic count (TAC), K and related values, adenosine triphosphate (ATP) and related compounds, color and sensory score were determined and correlation between these indicators were analyzed. According to the comprehensive evaluation of TAC, K value and sensory score, the limit for acceptability of rainbow trout fillets was 5days at 3°C and 11days at -3°C. Additionally, the correlation coefficients between TVB-N and other freshness indicators (TAC, K value, sensory score) were relatively low. TVB-N may be inadequate for evaluating freshness changes of rainbow trout fillets compared with other indicators. Among the K and related values, H value was a better freshness indicator in rainbow trout fillets during chilled and super chilling storage for its better correlation coefficients with other freshness indicators. Super chilling storage could extend the shelf life of rainbow trout fillets by 6days compared to chilled storage.

Paraplantaricin L-ZB1, a novel bacteriocin and its application as a biopreservative agent on quality and shelf life of rainbow trout fillets stored at 4 °c.

Paraplantaricin L-ZB1 was produced by Lactobacillus paraplantarum L-ZB1, which was isolated from the traditional China fermented sausage. In this work, paraplantaricin L-ZB1 was used to maintain quality of rainbow trout fillets at 4 °C. Rainbow trout fillets were left untreated (CK) or treated with 200 activity units (AU)/ml paraplantaricin L-ZB1 (P1), 400 AU/ml paraplantaricin L-ZB1 (P2) or 200 AU/ml Nisin (N). The treated samples were stored at 4 °C for up to 10 days, and the quality changes were determined by microbiological (total viable count [TVC], Enterobacteriaceae, Pseudomonas, spore-forming bacteria), sensory, chemical (pH, total volatile basic nitrogen [TVB-N]) and biochemical (biogenic amines, K value) methods. Results show that paraplantaricin L-ZB1 could inhibit the growth of microflora, especially Enterobacteriaceae, Pseudomonas and spore-forming bacteria during sample storage. Meanwhile, the increases of pH, TVB-N, K value and biogenic amine levels were significantly delayed in paraplantaricin L-ZB1-treated samples compared to the control group. Paraplantaricin L-ZB1 of 400 AU/ml extended the rainbow trout fillets' shelf life to 4-6 days, and the sample showed good sensory characteristics. Therefore, paraplantaricin L-ZB1 could be used as a suitable biological preservative for chilled rainbow trout fillets.

Use of quince seed mucilage edible films containing natural preservatives to enhance physico-chemical quality of rainbow trout fillets during cold storage

In this study quality changes of rainbow trout fillet wrapped with quince seed mucilage QSM film incorporated with 0–2% (V/V) thyme or oregano essential oil, as natural preservatives, during storage of 18d at 4°C were investigated. The control and wrapped fillet samples were analyzed for texture, lipid oxidation, and color characteristics. After 6d of storage, a significantly increasing trend was observed for lipid oxidation in control samples. Peroxidation values (PV) varied for all treatments and remained lower than 8meq/kg throughout the storage time (18d). The lowest PV was obtained in fillets wrapped with QSM film containing 2% oregano essential oil. Compared to control samples, fillet samples wrapped with QSM films presented a significant reduction in pH after 12d (P<0.05). L* and b* color parameters were increased while parameter a* was decreased linearly for all treatments during the storage time.

The Effects of Sodium Alginate on Quality of Rainbow Trout (Oncorhynchus mykiss) Fillets Stored at 4 ± 2°C

Edible coating is a novel food packaging technology for controlling the growth of spoilage bacteria and chemical changes in ready-to-eat food products. Fresh fish are highly perishable foodstuffs and are very susceptible to spoilage. A sodium alginate coating was used to maintain the quality of rainbow trout fillets in chilled storage over a period of 20 days. Fillet samples were coated with an aqueous solution of 3% sodium alginate and then stored at chilled temperature (4 ± 2°C). The control and coated samples were analyzed periodically (every 5 days) for microbial (aerobic plate count and psychrotrophic count), chemical (total volatile basic nitrogen, thiobarbituric acid, peroxide value), and sensory characteristics. The results indicated that the sodium alginate coating helped protect the quality characteristics of treated fresh fish fillets and prolonged the shelf life during chilled storage of rainbow trout fillets.

Effect of Dietary Vitamin E Supplementation and Refrigerated Storage on Quality of Rainbow Trout Fillets

Rainbow trout were fed a low vitamin E (200 mg/kg; LVE) or a high vitamin E (5000 mg/kg; HVE) diet for 9 wk to characterize the effect of vitamin E supplementation at 5000 mg/kg on fillet quality. Fish were sampled at 2, 3, 4, 5, 7, and 9 wk of the trial. Fillets were stored at 2 °C for 0, 7, and 14 d, and analyzed for pH, psychrotrophic counts, color, cook yield, shear force, crude fat and moisture content, α-tocopherol, fatty acid composition, and lipid oxidation. There was a significant feeding duration by fillet storage time interaction for psychrotrophic counts, crude fat content, cook yield, and shear force. Fillet L* value was not affected by diet, feeding duration or storage time. Fillet a* was lowest at 14-d storage, and b* values increased with fillet storage time. High vitamin E diet increased fillet α-tocopherol from 33 to 155 mg/kg. High vitamin E decreased palmitic acid and increased linoleic acid and omega-6 fatty acids. Feeding through 9 wk increased the relative proportions of unsaturated, polyunsaturated, and omega-3 fatty acids, and decreased saturated and omega-6 fatty acids. At 0-d storage, HVE diet did not affect thiobarbituric acid-reactive substances (TBARS) at any sampling week, and fasted fish generated fewer TBARS compared to non-fasted fish.

Effect of Soybean Meal‐based Diets on the Product Quality of Rainbow Trout Fillets

ABSTRACT: This study investigated the long‐term effects of soybean meal (SBM)‐based diets on rainbow trout quality. Two levels of SBM inclusion diets, 20% and 40%, were employed and compared with a fish meal control diet. Rainbow trout were fed one of the three diets for 6 mo, then harvested and filleted. Proximate composition, color, lipid oxidation and sensory quality of the fillets were evaluated. Thiobarbituric acid reactive substances (TBARS) and headspace propanal in ground fillets stored at 4 °C were measured over a 9‐d period. Tristimulus color was measured on day 2 and day 13 of refrigerated storage. Sensory evaluation included discriminatory (difference) and affective (acceptance) testing. TBARS and propanal in the trout fed the highest (40%) SBM level were significantly lower than in the control and trout fed the 20% SBM diet. Significant differences in color were also recorded during refrigerated storage. Sensory difference testing revealed a significant difference between the trout fed the 40% SBM and the control. No significant differences were observed in the acceptability ratings of trout fillets from the three different dietary treatments.