Oxidative stability and quality characteristics of whey protein coated rohu (Labeo rohita) fillets

Edible Xanthan/Propolis Coating and Its Effect on Physicochemical, Microbial, and Sensory Quality Indices in Mackerel Tuna (Euthynnus affinis) Fillets during Chilled Storage

Worldwide aquaculture production is increasing, but with this increase comes quality and safety related problems. Hence, there is an urgent need to develop potent technologies to extend the shelf life of fish. Xanthan gum is commonly used in the food industry because of its high-water solubility, stability of its aqueous solutions in a wide pH range, and high viscosity. One of its modern food applications is its use as a gelling agent in edible coatings building. Therefore, in this study, the effect of xanthan coating containing various concentrations (0, 1, 2%; w/v) of ethanolic extract of propolis (EEP) on physicochemical, microbial, and sensory quality indices in mackerel fillets stored at 2 °C for 20 days was evaluated. The pH, peroxide value, K-value, TVB-N, TBARS, microbiological and sensory characteristics were determined every 5 days over the storage period (20 days). Samples treated with xanthan (XAN) coatings containing 1 and 2% of EEP were shown to have the highest level of physicochemical protection and maximum level of microbial inhibition (p < 0.05) compared to uncoated samples (control) over the storage period. Furthermore, the addition of EEP to XAN was more effective in notably preserving (p < 0.05) the taste and odor of coated samples compared to control.

Ultrasound-assisted extraction of guava and papaya leaves for the development of functional shrimp patties

The current study was aimed to evaluate the effects of guava and papaya leaves extract on the antioxidant profile and their outcomes in the storage stability of shrimp patties. Total of seven treatments were prepared by employing guava leaf extract (GLE) and papaya leaf extract (PLE) including control. Both the extracts were employed in the concentration of 1% and 2% each and in combination as 1:1% and 2:2%, respectively. The shrimp patties were kept in ziplock bags at refrigeration temperature, and further analysis was done after 21 days of storage period with intermittent evaluation interval of 7 days. The antioxidant capability of functional shrimp patties was determined by total phenolic content (TPC), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and ferric reducing antioxidant power (FRAP). Higher significant values of TPC, DPPH, and FRAP were observed in the functional shrimp patties enriched with GLE2%:PLE2% at start of the experiment. The physicochemical parameters were observed by hunter color, TVBN, TBARS, and peroxide value (POV). Higher significant values of TVBN, TBARS, and peroxide were observed in the control samples as compared to treatment group GLE2%:PLE2%. The bacterial counts were also higher in control samples as compared to the treatment group GLE2%:PLE2%. The sensorial attributes were observed regarding appearance, taste, texture, odor, and overall acceptability. The maximum scores related all parameters were gathered by control group but significantly lower scores were for the group GLE2%:PLE2%. In conclusion, functional shrimp patties enriched with GLE2%:PLE2% showed better antioxidant capacity, stability, and sensory characteristics during storage.

Preservative Effects of Gelatin Active Coating Enriched with Eugenol Emulsion on Chinese Seabass (Lateolabrax maculatus) during Superchilling (−0.9 °C) Storage

This research was to evaluate the effects of gelatin (G) active coating containing eugenol/β-cyclodextrin (βCD) emulsions combined with superchilling (−0.9 °C) on physicochemical, microbiological, and organoleptic properties of Chinese seabass samples during 30 days of storage. Results showed that seabass samples dipped in G-βCD coatings containing 0.15% or 0.3% eugenol combined with superchilling could significantly lower the total volatile basic nitrogen, K value, total viable count, H2S-producing bacteria, Pseudomonas spp. and Psychrophilic counts, and free fatty acids. Further, G-βCD coatings containing eugenol with superchilling (−0.9 °C) were more effective in retarding the water migration by low field NMR and MRI results, maintaining quality of seabass during storage according to organoleptic evaluation results.

Effects of whey protein films on the quality of thawed bigeye tuna (Thunnus obesus) chunks under modified atmosphere packaging and vacuum packaging conditions

To improve the quality of modified atmosphere (60% CO₂/15% O₂/25% N₂)-packaged or vacuum-packaged bigeye tuna (Thunnus obesus) chunks, an edible film containing whey protein isolates (WPI) were added. During storage at 2 °C, the samples coated with WPI prior to packaging exhibited slower microbial growth, thiobarbituric acid (TBA), and total volatile basic-nitrogen (TVB-N) values than did those without films. On comparing the two formulations of WPI with 4 and 8% (v/v) glycerol, it was observed that WPI containing 8% glycerol induced more severe weight loss but retarded the lipid oxidation more effectively. The usage of WPI films with 8% glycerol is proved to be helpful to enhance the effect of modified atmosphere packaging on the quality of tuna, as the samples (MAP-2) displayed the lowest bacterial counts (3.63 log CFU/g) and TBA (0.349 mg malondialdehyde (MDA)/kg) and TVB-N (12.94 mg N/100 g) contents.