This study investigates the morphology, ultrastructure, and degeneration patterns of hydrated oocytes in captive broodstock of Acanthopagrus berda during the breeding seasons from 2022 to 2024. Ovarian biopsy samples consistently revealed the presence ofhydrated oocytes, identified as large, transparent, spherical cells that progressively degenerated when not spawned. Light microscopy and scanning electron microscopy (SEM) provided detailed insights into oocyte developmental stages, from early vitellogenic oocytes to hydrated oocytes (300-700 μm), with an emphasis on the degeneration of hydrated oocytes in female broodstock and hormone- induced females that failed to spawn. Notable surface changes included pore canal opening patterns and zona radiata folding, indicative of hydration-related structural modifications. Hydrated oocytes exhibited a smoother zona radiata with widely spaced pore openings compared to the densely pitted surface of mature oocytes. Progressive degeneration was characterised by membrane folding, shrinkage, rupture of the zona radiata, and eventual disintegration into irregular cellular debris. Similar patterns were confirmed in hormone induced females at an inshore hatchery, where hydrated oocytes retained within the ovarian lumen failed to ovulate and underwent similar degeneration. The degeneration process was marked by cytoplasmic collapse, persistent nuclei in early stages, and complete structural breakdown in advanced stages. The study underscores the importance of optimising hormonal treatment protocols and environmental conditions to prevent oocyte retention and to improve reproductive outcomes in marine fish broodstock management.
Fish is a key protein source in coastal urban diets, yet market-related factors shape consumer purchasing behaviour. This study examines direct fish purchasing behaviour at physical markets in Mumbai City and Mumbai Suburban regions, based on a survey of 180 consumers across eight markets (April–June 2024). Using Rank-Based Quotient and Normalized Response Priority Index methods, taste (92.94), nutritive value (88.22), and freshness (86.63) emerged as the top selection factors. Market hygiene was the leading constraint in Mumbai City (NRPI: 0.84), while market hygiene (0.71) and price fluctuation (0.70) were the leading constraints in Mumbai Suburban markets, with significant regional differences (p < 0.01) in hygiene perception. Findings are limited to consumers purchasing fish directly from markets.
The present study aimed at developing a fibre-incorporated surimi gel with improved functional properties by incorporating banana pseudostem flour (BPF), an abundant agro-industrial waste, into Nemipterus japonicus (Japanese threadfin bream) surimi. Surimi gel with varying concentrations of BPF (0-5%) was prepared using trial and error method and named as S1 (0%), S2 (1%), S3 (2.5%), and S4 (5%). Results indicated that S4 significantly improved (p < 0.05) gel strength, water-holding capacity, and sensory acceptability of the gel, although it caused a slight reduction in whiteness. The incorporation of 5% BPF (S4) was found to be optimal for enhancing the dietary fibre content without compromising the quality of the surimi gel. The total dietary fibre content of S4 was 2.52 ± 0.06%. Addition of BPF also significantly improved the thermal stability of surimi gel, as evidenced by an increase in the first endothermic peak temperature from 33.67 °C in S1 to 50.71 °C in S4 in Differential Scanning Calorimetry (DSC) analysis. Thermal stability analysis and structural characterisation were performed to compare the differences between S1 and S4. Scanning electron microscopy revealed a denser, more heterogeneous structure in S4 than in S1. Addition of BPF modified the surimi microstructure by promoting protein–fibre interactions, resulting in a more integrated network that enhances gel strength and waterholding capacity. Fourier transform infrared spectroscopy (FTIR) results confirm that BPF incorporation does not disrupt the fundamental protein structure but rather promotes intermolecular interactions, thereby improving gel network stability and functional properties. Overall, this study demonstrates that banana pseudostem flour, a valuable secondary raw material, can be effectively utilised at an optimal level of 5% to enhance the functional properties of surimi gel.
Online marketplaces are booming, and in cities like Kochi, Kerala, many households rely on them for supplies, including fish. Antimicrobial resistance is a growing trend across the food sector. Therefore, this research investigated the presence of cefotaxime resistant Escherichia coli in fish sold through these online platforms. A total of 100 fish samples obtained from online retailers in Kochi, India, were screened for cefotaxime-resistant E. coli using MacConkey agar supplemented with cefotaxime (1 μg/mL). Confirmed isolates underwent antimicrobial susceptibility testing (17 antibiotics), double disc synergy testing (DDST), and PCR detection of ESBL-associated genes (blaCTX-M-1, blaCTX-M-2, blaCTX-M-9, blaTEM, blaSHV, blaOXA-1-like). Multiple antibiotic resistance (MAR) index and multidrug resistance (MDR) of the isolates were calculated. Cefotaxime-resistant E. coli was detected in 28% of samples, yielding 57 isolates. Among these, 85.9% (49/57) were multidrug resistant (MDR). High resistance was observed to amoxicillin-clavulanic acid (98%), followed by cefpodoxime (84%) and ceftazidime (60%). Phenotypic ESBL production was confirmed in 67% (36/ 57) of isolates. However, ESBL-associated genes were detected in a smaller proportion: blaCTX-M-1 (16.6%), blaTEM (20.8%), and both genes (4.1%). No isolates carried blaSHV or blaOXA-1-like genes. The MAR index ranged from 0.059 to 0.824, with 37% of isolates exhibiting MAR > 0.2. While cefotaxime resistance enabled selection of multidrug-resistant isolates, molecular confirmation demonstrated that only a subset carried ESBL genes, suggesting additional resistance mechanisms were involved. These findings highlight the importance of surveillance of antimicrobial-resistant E. coli in emerging food distribution systems such as online seafood markets.
This study optimised brine blanching conditions to produce freeze-dried shrimp bites from Parapenaeopsis stylifera using a multilevel factorial design. The effects of brine concentration (1%, 2%, 3% w/v) and blanching duration (1, 3, 5, and 7 min) at 90 °C were assessed on physicochemical, sensory, and structural quality attributes, including blanching loss, sensory acceptability, rehydration ratio, water activity, colour parameters, salt content, astaxanthin content, and texture properties. Both processing variables significantly affected most measured quality attributes, although the magnitude and significance of the main and interaction effects varied across responses. Short-time, low-salt treatments (1–3 min, 1–2% brine) yielded the highest sensory acceptability and rehydration capacity, while effectively preserving colour and texture. Multi-response optimisation identified 3 minutes of blanching at 2% brine concentration as optimal, achieving a composite desirability of 0.511. In contrast, extended treatments (5–7 min, 3% brine) enhanced preservation traits by lowering water activity and improving astaxanthin content, but reduced sensory appeal and rehydration performance. Colour analysis showed that minimal processing better maintained lightness, whereas longer treatments intensified red–yellow pigmentation due to controlled carotenoid release. Texture firmness increased progressively with processing intensity, likely due to enhanced formation of the protein gel network. Overall, the study shows how brine concentration and blanching time can be adjusted to achieve a suitable balance among the physicochemical, textural, rehydration, and sensory properties of freeze-dried shrimp bites.
