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Suitability of Pangasius as a source for salt fermentation and its physicochemical and microbiological changes during fermentation were evaluated for a period of 150 days. Biochemical and microbiological parameters such as proximate composition, pH, non-protein nitrogen, total volatile base nitrogen, free α-amino nitrogen, free fatty acid, peroxide value, thiobarbutric acid reactive substances, salt content, total titratable acidity, total viable count, and Escherichia coli were analyzed during the fermentation. Peroxide value and thiobarbutric acid reactive substances indicated that maturation started on the 90th day of fermentation. The highest non-protein nitrogen (NPN)/total nitrogen (TN) ratio was observed on the 120th day and the highest sensory scores were observed on the 150th day of fermentation. NPN/TN ratio and sensory scores showed that salt fermentation accelerate from the 90th day and attains maturation on the 120th day. The study revealed that Pangasius can be an ideal fish for salt fermentation, and this technique can be adopted by small-scale farmers. [ABSTRACT FROM AUTHOR]

Application of High pressure and low temperature setting condition on microbial transglutaminase (MTGase) mediated gelation was studied against conventional cooking in pink perch mince. A high pressure of 250 MPa was given to pink perch mince samples added with and without MTGase enzyme, for a holding time of 12 min and a setting condition of 25 °C for 30 min was given prior and after the treatments. Nine random experiments (T1 to T9) were made against high pressure and cooking and analysed its textural and functional properties. Addition of MTGase and setting conditions had significant effect on the textural properties of the both samples especially in inducing the gel strength. Reduction in total and reactive sulfhydryl groups observed was due to the formation of disulfide linkages, which was found more in T6 to T9. Setting condition had significant effect on protein hydrophobicity in both pressure and heat induced gels. No significant variation in the Ca2+-ATPase enzyme activity was observed among treatments. SEM images revealed more closed and dense fibrous network in samples with enzyme (T6 to T9), due to more protein polymerisation. So MTGase enzyme along with pressure treatment enhanced the conformational stability and produce stronger networks through the formation of non sulfide bonds between proteins and setting reinforced these networks. Hence the synergistic effect of high pressure and MTGase can enhance the textural and functional properties of fish gels, when compared with the conventional cooking. [ABSTRACT FROM AUTHOR]

Abstract: The aim of the present study was to develop an extruded product fortified with seaweed (Sargassum tenerrimum) using a co-rotating twin screw extruder and to optimize the process parameters using response surface methodology. The Box-Behnken design was employed with three independent variables i.e. feed moisture (X1), Sargassum powder level (X2) and barrel temperature (X3) with three levels for designing the experiment. The expansion ratio and porosity were considered as response variables. Feed moisture had the most significant (p < 0.05) linear effect on both the response variables whereas Sargassum level and barrel temperature shown significant (p < 0.05) quadratic effect. The optimum level of independent variables i.e. feed moisture, Sargassum level and barrel temperature for maximum expansion ratio were 16.45%, 4.33% and 123.08 °C respectively whereas for maximum porosity were 16.06%, 4.51% and 124.04 °C respectively. The present investigation can be used to develop extruded products fortified with seaweeds as functional food using the optimized process condition as a means to increase the nutritional quality of the traditional extruded snacks which is considered as a junk food.Graphical Abstract: [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: Functional extruded snacks were prepared using paste shrimp powder (Acetes spp.), which is rich in protein. The process variables required for the preparation of extruded snacks was optimized using response surface methodology. Extrusion temperature (130–144 °C), level of Acetes powder (100–200 g kg−1) and feed moisture (140–200 g kg−1) were selected as design variables, and expansion ratio, porosity, hardness, crispness and thiobarbituric acid reactive substance value were taken as the response variables. RESULTS: Extrusion temperature significantly influenced all the response variables, while Acetes inclusion influenced all variables except porosity. Feed moisture content showed a significant quadratic effect on all responses and an interactive effect on expansion ratio and hardness. Shrimp powder incorporation increased the protein and mineral content of the final product. The extruded snack made with the combination of extrusion temperature 144.59 °C, feed moisture 178.5 g kg−1 and Acetes inclusion level 146.7 g kg−1 was found to be the best one based on sensory evaluation. CONCLUSION: The study suggests that use of Acetes species for the development of extruded snacks will serve as a means of utilization of Acetes as well as being a rich source of proteins for human consumption, which would otherwise remain unexploited as a by‐catch. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The present study was carried out to examine the effect of gelatin-based coating solutions enriched with natural preservative agents like chitosan, garlic ( A llium sativum) and lime ( C itrus aurantifolia) on quality and shelf life of refrigerated fresh Indian salmon ( E leutheronema tetradactylum) fillets. Three different coating solutions were prepared (T1: 10% gelatin; T2: 10% gelatin + 1.5% chitosan + 30% lime juice; T3: 10% gelatin + 1.5% chitosan + 30% garlic extract) and evaluated for antimicrobial activity. The antimicrobial activity of coating solutions was evaluated against eight fishborne pathogens and spoilage bacteria by agar well diffusion and micro broth dilution methods. The coating formula was found to be highly efficient in extending the shelf life of Indian salmon fillets up to 16 days in refrigerated storage by dip treatment. Among the three different treatments, garlic containing coating solution (T3) was found to be the best in extending the shelf life of fish fillets. Practical Applications The need for natural edible coatings in food industry is of great demand and it is challenging to have natural compounds exhibiting better preservative role as comparable with chemical preservatives. The present study evidenced that edible coatings made of gelatin, chitosan and garlic/lime extracts exhibit preservative action and extend the shelf life of fish fillets. [ABSTRACT FROM AUTHOR]

Extrusion cooking plays an important role in the production of puffed snacks, which enjoy wide acceptance all over the world and are potential vehicles for increasing the consumption of n-3 fatty acids. Response surface methodology (RSM) with central composite design was adopted to investigate the effects of four independent variables (fish powder, fish oil, moisture, and screw speed) at five levels on expansion ratio, breaking strength index, hardness, color, and thiobarbituric acid reactive substances (TBARS). A second order polynomial model was used to study the main, interactive, and quadratic effects of the independent variables and to explain the relationship between the responses and independent variables. Moisture was found to be the most significant factor (p< 0.001) influencing expansion ratio, breaking strength index, and color. Inclusion of fish powder and fish oil were found to be negatively associated with the expansion characteristics, resulting in decreased lipid oxidation due to less exposed surface area of the extrudates to air. Further, the absence of linear effect of fish powder and fish oil on TBARS demonstrated the possibility to incorporate higher levels of these ingredients to produce oxidatively stable extruded snacks rich in fish proteins. [ABSTRACT FROM PUBLISHER]

Utilization of shrimp head waste from the processing industry offers a solution to environmental pollution and also produces valuable bioactive peptides. The present study was aimed to optimize the alcalase assisted extraction conditions by response surface methodology (RSM) to obtain protein hydrolysates from shrimp (Metapenaeus dobsoni) head waste with maximum antioxidant activity. Based on the models derived by RSM, the optimized conditions for maximum degree of hydrolysis (DH) were pH 8.2, temperature of 45.4°C, and enzyme/substrate (E/S) of 1.8%. Meanwhile, the optimized conditions for maximum antioxidant activity of protein hydrolysates as measured by 2, 2-diphenyl-1-picrylhydrozyl (DPPH) and ferric reducing antioxidant power (FRAP) assays were pH 8.2 and 8.1, temperatures of 49.7 and 59.4°C, and E/S of 2.1 and 2.7%, respectively. The maximum predicted values for DH, DPPH, and FRAP were 42.44%, 39.64% inhibition, and 8.3μM Fe (II)/g wet wt. of sample, respectively. The extraction of protein hydrolysates at optimal conditions derived by these models resulted in DH, DPPH, and FRAPs of 40.31%, 38.93%, and 8.21μM Fe (II)/g of sample, respectively, demonstrating the fitness of the models. The present study demonstrates the potential ofMetapenaeus dobsonihead waste as a source of protein hydrolysates with prospective antioxidant activity. [ABSTRACT FROM AUTHOR]

Fortification of cakes with fish oil encapsulates was performed to enhance the consumption of health-beneficial polyunsaturated fatty acids like eicosapentaenoic acid and docosahexaenoic acid. Fish oil-in-milk emulsions prepared by ultrasonication at different amplitudes were encapsulated by spray drying using different wall materials. The oxidative stability of fish oil encapsulates was determined for 32 days at room and refrigerated temperatures. Oxidatively stable encapsulates and organoleptic quality of fortified cakes reveal that emulsification of fish oil-in-milk and encapsulation by spray drying are potential processes to produce fish oil encapsulates suitable for fortification of bakery products with omega-3 fatty acids. [ABSTRACT FROM AUTHOR]

ABSTRACT The antibacterial activity of essential oils (EOs) isolated from ginger ( Zingiber officinale), eucalyptus ( Eucalyptus camaldulensis) and sweet orange ( Citrus sinensis) was evaluated against fish spoilage and fish-borne pathogenic bacteria by agar well diffusion and microbroth dilution method. Chemical profiles of EOs by gas chromatography-mass spectrometer revealed that zingiberene, α-phellandrene and limonene were the major components of ginger, eucalyptus, and sweet orange EOs, respectively. Among the three EOs evaluated, ginger oil had the best antibacterial activity against all the bacteria tested. Bacillus subtilis was found as the most sensitive bacterium against ginger EO. Vibrio parahaemolyticus and Aeromonas hydrophila were the most resistant to all the EOs. Antibiotic resistant Yersinia enterocolitica was found as the most sensitive bacteria among gram-negative bacteria tested. PRACTICAL APPLICATIONS The results of the present study reveal the scope of the plant essential oils (EOs) in the shelf life extension of fish. The fresh fish after catching need to be ice-preserved before undergoing further processing. In addition, the preservation during the postharvest handling and transportation of fish is important, during which there are chances for microbial contamination from the food contact surfaces, containers and transport vehicles. The use of plant EOs will definitely help in reducing the level of microbial contamination, preserving the fish and extending their shelf life. They are cheaper in economical terms as well and easy to use by dip or spray treatment. The fishermen can use the plant EOs onboard to preserve the fish. The retailers and vendors can use it for the quality maintenance of fish. [ABSTRACT FROM AUTHOR]

The study was aimed at evaluating three polymer hydrocolloids from aquatic sources in batter composition for developing enrobed fish fingers with less oil uptake and improved coating properties. Alginate, chitosan, and fish gelatin were incorporated at 1% (wt/wt) level in batter mix and coating parameters such as coating pickup, adhesion degree, frying loss, and cooked yield were studied. Proximate composition, chemical quality parameters, and oil absorption/oil reduction due to hydrocolloids were studied, and the results indicated that chitosan‐treated fish fingers are found to have better coating functions, biochemical quality with lower total volatile basic nitrogen value (6.02 mg/100 g), peroxide value (0.05 meq O2/kg), and thiobarbituric acid reactive substances (0.15 MDA/kg fat) than alginate and gelatin treated samples. The results indicated that lowest fat uptake (3.73%), lowest hardness value, and highest fat reduction were observed in fish finger coated with chitosan containing batter. Among the three aquatic polymers evaluated, chitosan was found to be more effective in oil reduction and physicochemical quality improvement as compared to alginate and fish gelatin. Practical applications: This study highlights the screening and evaluation of three biological macromolecules of aquatic origins such as alginate, chitosan, and gelatin for the development of battered and breaded fish finger with better functional qualities including minimum oil absorption and improved shelf‐life. The outcome of this work can be used to extend the development of functional fishery products, and it can be utilized to extend the market potential of alginate and chitosan and promote the battered and breaded product consumption with more health benefits. [ABSTRACT FROM AUTHOR]

Chitosan is a natural polymer having diverse applications in food industry. The present study was undertaken to evaluate chitosan as a hydrocolloid in batter composition in developing enrobed fish sticks with better functional properties and improved quality. Different concentrations of chitosan gel were made in acetic acid medium and incorporated into batter for making enrobed fish sticks. Coating parameters, fat uptake, oil reduction, chemical quality parameters, instrumental texture analysis and colour were studied. Addition of chitosan gel had a significant effect (P < 0.05) on the coating pickup, adhesion degree and cooking yield of the product. Total volatile basic nitrogen, pH, lipid oxidation parameters like peroxide value and thiobarbituric acid reactive substances of par-fried fish sticks also showed significant differences. The oil reduction in par-fried samples were 36.84, 65.05, 73.83, 77.65% respectively for 0.5, 1.0, 1.5, 2.0% chitosan added samples. Addition of chitosan significantly reduced crispness, gumminess, Warner-Bratzler shear force and toughness (P < 0.05) of the product. The study clearly demonstrated that the inclusion of chitosan at 1.0% in batter can improve functional and other quality aspects of enrobed products. [ABSTRACT FROM AUTHOR]