Microplastic contamination in salt-cured fish and commercial sea salts: an emerging food safety threat in relation to UN Sustainable Development Goals (SDGs).

Microplastic (MP) contamination in seafood, particularly processed varieties like dried and salt-cured fish, poses a significant threat to human health. This study investigated MP levels in 22 salt-cured fish species and commercial sea salts along the Indian east coast. Results showed substantially higher MP concentrations compared to global averages, with fragments and fibres (< 250 µm) composing 70% of identified MPs, primarily PVC and PS polymers (> 55%). Station 2 exhibited high pollution levels, with salt-cured fish averaging 54.06 ± 14.48 MP items/g and salt containing 23.53 ± 4.2 MP items/g, indicating a high hazard risk index. A modest correlation was observed between MP abundance, morphotypes, polymer composition in the salt, and their impact on fish products. Given the critical link between food safety, security, and public health, further research is imperative to mitigate MP contamination, aligning with UN Sustainable Development Goals (Goal 2, Goal 3, Goal 14, and Goal 15) for enhanced food safety and security.

Extraction, optimization, and functional quality evaluation of carotenoproteins from shrimp processing side streams through enzymatic process.

The study aimed to develop an effective and eco-friendly enzymatic process to extract carotenoproteins from shrimp waste. The optimization of enzymatic hydrolysis conditions to maximize the degree of deproteinization (DDP) of carotenoprotein from shrimp head waste (SHW) and shrimp shell waste (SSW) was conducted separately using the Box-Behnken design of response surface methodology (RSM). To achieve a maximum DDP of 92.32% for SSW and 96.72% for SHW, the optimal hydrolysis conditions were determined as follows: temperature (SSW: 53.13 °C; SHW: 45.90 °C), pH (SSW: 7.13; SHW: 6.78), time (SSW: 90 min; SHW: 61.18 min), and enzyme/substrate ratio (SSW: 2 g/100 g; SHW: 1.18 g/100 g). The carotenoprotein effluent obtained was subjected to spray drying and subsequently assessed for color, nutritional, and functional characteristics. The carotenoprotein from shrimp shell (CpSS) contained a higher essential amino acid score than carotenoprotein from shrimp head (CpSH). CpSS had a higher whiteness index of 82.05, while CpSH had 64.04. Both CpSS and CpSH showed good functional properties viz solubility, emulsion, and foaming properties. The maximum solubility of CpSH and CpSS was determined to be 92.94% and 96.48% at pH 10.0, respectively. The highest emulsion capacity (CpSH: 81.33%, CpSS: 70.13%) and stability (CpSH: 57.06%, CpSS: 63.05%) were observed at 3% carotenoprotein concentration. Similarly, the highest values of foaming capacity (CpSH: 27.66%, CpSS: 105.5%) and stability (CpSH: 23.83%, CpSS: 105.33%) were also found at the same 3% carotenoprotein concentration. In conclusion, the carotenoproteins obtained from shrimp waste showed favorable attributes in terms of color, amino acid composition, and functional properties. These findings strongly suggest the potential applicability of CpSS and CpSH as valuable resources in various domains. CpSS, with its higher whiteness index, greater amino acid content, and superior functional characteristics, may find suitability as functional ingredients in human food products. Conversely, CpSH could be considered for incorporation into animal feed formulations.

Comparative efficiency of native and non-native starter culture in the production of bio-silage using composite waste from fish and vegetables.

The efficiency of native and non-native starter cultures in the production of bio-silage using composite waste from fish and vegetables was studied. An ensilage experiment was conducted in a natural way (without starter culture) of composite waste (fish to vegetable at 80 to 20%) to isolate the native fermentative microflora. An Enterococcus faecalis strain isolated from the natural ensilage of composite waste showed higher efficiency over other commercial LAB strains generally used for ensilation. A total of 60 isolates were screened and characterized biochemically from ensilaged composite waste. Among them, 12 proteolytic and lipolytic positive isolates were identified as Enterococcus faecalis, based on a BLAST search of the 16S rRNA gene sequences. Subsequently, composite bio-silage was prepared by inoculating starter cultures with three (3) treatments T1 (native-Enterococcus faecalis), T2 (non-native-Lactobacillus acidophilus), T3 (a mixture of E. faecalis and L. acidophilus) and compared with control (composite bio-silage without starter culture). The highest non-protein nitrogen (0.78 ± 0.01 mg of N /100 g) and degree of hydrolysis (70.00 ± 0.06% of protein/100 g) was seen in the T3 sample, and the lowest (0.67 ± 0.02 mg of N/100 g and 50.40 ± 0.04% of protein/100 g) was seen in the control. At the end of ensilation, the pH fell (5.95-3.88) in conjunction with the formation of lactic acid (0.23-2.05 g of lactic acid/100 g), and the lactic acid bacteria count nearly doubled (log 5.60-10.60). The lipid peroxidation products PV (0.11-0.41 milli equivalent of oxygen/kg of fat) and TBARs (1.64-6.95 mg of malonaldehyde/kg of silage) were changed within a reasonable range in the following pattern Control > T2 > T3 > T1, which led to oxidatively stable products. The findings revealed that native starter culture E. faecalis, which can be employed as a single or in combination with non-native L. acidophilus, performed better in the bio-ensilation process. Additionally, the finished composite bio-silage can be used as a novel, protein-carbohydrate rich feed component to help manage wastes from both sectors.

Comparative analysis of unwashed and single washed mince gel from Indian major carps.

The gelling properties and quality characteristics of unwashed and single washed mince of catla, rohu and mrigal have been investigated to find out suitability of Indian major carps for the preparation of mince gel. The higher moisture content and lower protein content was reported in the single washed mince. The single washing of mince did not improve the gel strength. The gel strength showed significant difference (p < 0.05) and decreased in single washed mince than its unwashed counterparts in catla and mrigal except rohu. It has been observed that gel did not set at pre-incubation temperature of 40 °C for 30 min treatment. SDS-PAGE patterns of proteins did not show any loss of myosin heavy chain (MHC) in single washed mince of Indian major carps. Texture profile analysis showed higher hardness in washed mince gel of Indian major carps while, non-significant difference (p > 0.05) was observed in cohesiveness, adhesiveness and elasticity properties. The whiteness index of washed mince showed improvement. The overall study indicated that mince gels can be made from unwashed mince of Indian major carps, alleviating the problems of waste water disposal leading to production of more value added products with better nutritional value.

Effects of lysine and arginine on the properties of low-salt mince gel from striped catfish (Pangasianodon hypophthalmus).

Effects of basic amino acids, lysine (Lys) and arginine (Arg), at different levels (0%, 0.5%, and 1%, based on mince weight) on properties of striped catfish (Pangasianodon hypophthalmus) mince gel containing low salt (LS) and high salt (HS) were investigated. Without Lys or Arg addition, HS gel had the higher textural properties including hardness, chewiness, as well as cohesiveness than LS gel (P < 0.05) and the highest values were achieved when 1% Arg was incorporated in both LS and HS gels (P < 0.05). Arg had no effect on acceptability of mince gel. However, whiteness was decreased in HS gel when Arg was applied. Autolysis of gel was lower in HS gel containing Arg. No differences in protein patterns among all gel samples were found. Addition of Arg could increase the gelling ability of both LS and HS mince during heating as evidenced by higher storage modulus (G') and viscous modulus (G″). Mince gel added with Arg had orderly interconnected structure and their microstructure was finer than that without Arg. Therefore, Arg could be used in LS gel from striped catfish mince, in which quality of gel was equivalent to HS counterpart. PRACTICAL APPLICATION: Basic amino acid, especially arginine (Arg) with guanidinium group, could increase repulsive force between protein molecules at low-salt concentration (0.5%). This resulted in high solubilization of muscle proteins, whereas gel formation or gel strength was higher than that containing high salt (2.5% to 3.5%). Thus, Arg could be used for production of fish mince gel containing low salt with lowered health risk.

Chitosan hydrogel inclusion in fish mince based emulsion sausages: Effect of gel interaction on functional and physicochemical qualities.

Chitosan has been reported to possess diverse applications in food industry. The cross linking properties of chitosan beneficially affects the protein-carbohydrate interactions which in turn enhances the functional properties in emulsion based meat products. In this context, the current study was conducted to incorporate hydrogel with different concentrations of chitosan (0%, 0.125%, 0.25%, 0.375% and 0.5%) into fish mince (Pangasianodon hypophthalmus) sausages in order to develop a functional sausage products with appealing flavour and desirable texture. The comparative analysis of various functional properties of the produced sausages showed that inclusion of chitosan gel had significant effect (p < 0.05) on the emulsion stability, gel-strength, pH, cooking yield, WHC, structural-compactness, texture, colour and sensory attributes of the products when compared with control. Further, from the study, it can be inferred that, sausages with 0.25% chitosan content (CS-2) uphold the best necessary functional and physiochemical attributes and presumed to be a superior ready-to eat product.

Antioxidant properties and instrumental quality characteristics of spray dried Pangasius visceral protein hydrolysate prepared by chemical and enzymatic methods.

Fish protein hydrolysates are digested form of protein with various bioactive properties where, the cleavages of molecular bonds of proteins can be broken by the enzymatic and chemical process. In this study, antioxidant properties of spray dried protein hydrolysate prepared from Pangasius viscera by using enzymatic (papain and pepsin), and chemical methods (hydrochloric acid and sodium hydroxide) were evaluated. Among the different treatments, pepsin-derived visceral protein hydrolysate showed the maximum antioxidant activity when used at higher concentrations. Essential amino acids (EAA) and hydrophobic amino acids are higher in papain-derived visceral protein hydrolysate. In pepsin-derived visceral protein hydrolysate, major proportion was contributed by glycine (Gly), glutamine (Glu), proline (Pro), and asparagine (Asp). Higher amount of aromatic amino acids are found in alkali-derived FVPH. Scanning electron microscopy (SEM) images of pepsin fish visceral protein hydrolysate showed better globular structure than the other treatments. It can be concluded that among the different treatments, the visceral protein hydrolysate prepared with pepsin had better overall quality regarding antioxidant properties and papain in nutritional point of view.