Aquatic Product Processing Research Articles

Influence of (ultra-)processing methods on aquatic proteins and product quality.

Aquatic products are a high-quality source of protein for humans, and the changes in protein during aquatic product processing are crucial for nutritional value, product performance, and consumer health. With the advancement of science and technology, aquatic product processing methods have become increasingly diverse. In addition to traditional methods such as thermal processing (steaming, roasting, and frying) and pickling, emerging non-thermal processing technologies, such as high pressure, ultrasound, and irradiation, are also being applied. During (ultra-)processing, aquatic products undergo complex biochemical reactions, among which protein oxidation significantly affects the quality of aquatic products. Protein oxidation can alter the molecular structure of proteins, thereby changing their functional properties and ultimately impacting product quality. This paper primarily explored the effects of protein changes under different processing methods on aquatic product quality and human health, as well as techniques for controlling protein oxidation. It aims to provide a theoretical basis for selecting appropriate processing methods, improving aquatic product quality, and controlling protein oxidation in aquatic products, and to offer scientific guidance for practical production.

Editorial: The aquatic product processing and by-product utilization

Editorial: The aquatic product processing and by-product utilization

Modification of steel slag and its application for phosphate and ammonia removal in aquatic products processing wastewater

ABSTRACT This study aims to modify different types of steel slag by heating, characterise the material and test its ability for adsorption of phosphate and ammonia from aquatic products processing wastewater. The materials were characterised by SEM, EDS, BET and FT-IR analyses. The effects of the type of steel slag, calcination temperature in steel slag modification, pH, contact time, adsorbent mass and initial pollutant concentration were investigated using the one-factor-at-a-time approach. The results show that the adsorption kinetic of the samples followed the pseudo-second-order model, whereas their adsorption isotherm fitted well with the monomolecular adsorptive Langmuir with a maximum phosphate adsorption capacity of 45.045 mgPO43-/g. Optimisation using Response Surface Methodology was conducted with the independent factors (adsorbent doses, contact time and calcination temperature of steel slag) and response (removal efficiency of phosphate). The temperature and dosage of the material significantly affected phosphate removal efficiency and optimisation conditions were suggested. Validation of one optimum condition at the calcination temperature of 801°C, the adsorbent dosage of 11.9 g/L and the contact time of 72 min using real aquatic products processing wastewater resulted in the removal efficiencies of 86.93, 87.59, 7.76 and 7.58% for phosphate, total phosphorus, ammonia and total nitrogen, respectively.

The interaction of Lactiplantibacillus plantarum and Latilatilactobacillus sakei regulated the formation of characteristic quality attributes of low-salt fermented tilapia

The regulation of quality characteristics of fermented aquatic food based on microbial metabolic interaction is a hot spot in the innovative processing of aquatic products around the world. In this study, electronic sensory system, gas phase method and liquid phase method based on mass spectrometry were used to study the effects of the interaction between Lactiplantibacillus plantarum and Latilactobacillus sakei on the quality and flavor of dry-cured tilapia. The targeted supplementation of Latilactobacillus sakei S199 can improve the texture and flavor characteristics of tilapia meat fermented by Lactiplantibacillus plantarum 550. Latilactobacillus sakei S199 can cross metabolize with Lactiplantibacillus plantarum 550 to produce more 1-Octen-3-ol, 3-methyl-1-Butanol, 1-Hexanol, 2-ethyl-1-Hexanol, (E)-2-Octen-1-ol, 2-Heptanone, 3-Octanone, 2-Pentyl-Furan, and 2,5-diethyltetrahydro-Furan, and reduce the content of Heptanal, Nonanal, and Benzaldehyde to enhance the aroma of fermented tilapia fish. The aroma intensity increased by three times, from 129.46 μg/kg to 373.02 μg/kg, white the bitterness of tilapia meat fermented by the two bacteria was reduced by half, from 231.26 μg/g to 153.65 μg/g. The interaction of Lactiplantibacillus plantarum 550 and Latilactobacillus sakei S199 promoted proteolysis and utilized the FAAs and other small molecular compounds to generate other flavor compounds. The results were helpful to understand the effect of the interaction between Lactiplantibacillus plantarum 550 and Latilactobacillus sakei S199 on the flavor formation of dry cured tilapia.

Evaluation of Proximate, Organoleptic and Vitamin C Changes of Seaweed Jelly Candy (Gracillaria Sp.) after the Addition of Honey Mango Juice

Aims: to determine the effect of the addition of honey mango juice on the characteristics of jelly candy Study Design: This research was designed using a completely randomized design (CRD) with four treatments namely A (addition of 0% mango juice), B (addition of 9.93%% mango juice), C (addition of 12.5% mango juice) and D (addition of 16.07% mango juice) with 2 replications. Proximate and sensory data of jelly candy were analyzed by analysis of variance (ANOVA) and followed by honest real difference test at α5% level Place and Duration of Study: This research was conducted at the Makassar Health Laboratory Center (Chemical Testing) and Departemen of Aquatic Product Processing and Storage Workshop (Organoleptic Test) of Pangkep State Polytechnic of Agriculture from April to July 2024. Methodology: The analysis conducted in this study included chemical and organoleptic analysis. Chemical analysis included: analysis of water content by distillation method, total sugar content. Vitamin C levels through iodometric titration. Organoleptic (sensory) analysis included Odor, taste, texture and color. Results: The results showed that the addition of mango juice to the characteristics of jelly candy was significantly different to water content, total sugar content and vitamin C. The best product based on chemical analysis is jelly candy in treatment D with the highest vitamin C content (5520.1 µg/g) and the highest total sugar content (38.92%) while the lowest water content (11.21%) was found in treatment A. Tests on organoleptic assessment of the highest panelists in treatment D, namely Odor 3.8 (like), taste 4.2 (like), texture 3.2 (normal), and color 3.7 (like).

Assessment and Spatio-Temporal Evolution of Marine Fisheries’ Carbon Sink Capacity in China’s Three Marine Economic Circles

With the increasing pressure of resource decline and environmental pollution faced by the green transformation of marine fisheries, marine fishery carbon sinks are an increasingly close link to national strategic interests and economic lifelines. It is, therefore, necessary to explore paths for the enhancement and development of the carbon sink capacity of marine fisheries. Based on the economic data of marine fisheries from 2002 to 2021, this paper measures the capacity and characteristics of marine fishery carbon sinks in provincial areas, applies the kernel density estimation method to depict the dynamic evolution of the distribution of absolute differences in marine fishery carbon sinks, and at the same time, identifies the factors influencing the spatial imbalance in the development of marine fishery carbon sinks as well as the spatial spillover effects. The results show the following: (1) From the total amount, the fishery carbon sink capacity of China’s three marine economic circles has fluctuated and increased over the past 20 years, with obvious differences among different circles, and the marine fishery carbon sink capacity of the eastern, northern, and southern marine economic circles has risen sequentially. This trend corresponds to the economic disparities among the three circles, demonstrating a transition from economic to industrial driving effects. (2) From the spatial point of view, the fishery carbon sink capacity shows a trend of increasing year by year, concentrating in the circles, and overflowing between the circles. (3) The results of a partial derivative test further show that among the main influencing factors of marine fishery carbon sinks, capital, labor, and market openness have direct positive effects on marine fishery carbon sinks, and the direct effect of innovation is the strongest, and the significance of the indirect effect of the three circles is weaker compared to the direct effect and total effect. As a result, the carbon sink of China’s marine fisheries has a large room for improvement, and in order to promote the high-quality development of China’s marine fisheries, it is still necessary to accelerate the circulation of resources within the marine economic circle, accelerate the research of fishery technology, actively develop the carbon sink fishery, and enhance the specialization of aquatic product processing.

Correlations of dynamic changes in lipid and protein of salted large yellow croaker during storage

Protein and lipid are two major components that undergo significant changes during processing of aquatic products. This study focused on the protein oxidation, protein conformational states, lipid oxidation and lipid molecule profiling of salted large yellow croaker during storage, and their correlations were investigated. The degree of oxidation of protein and lipid was time-dependent, leading to an increase in carbonyl content and surface hydrophobicity, a decrease in sulfhydryl groups, and an increase in conjugated diene, peroxide value and thiobarbituric acid reactive substances value. Oxidation caused protein structure denaturation and aggregation during storage. Lipid composition and content changed dynamically, with polyunsaturated phosphatidylcholine (PC) was preferentially oxidized compared to polyunsaturated triacylglycerol. Correlation analysis showed that the degradation of polyunsaturated key differential lipids (PC 18:2_20:5, PC 16:0_22:6, PC 16:0_20:5, etc.) was closely related to the oxidation of protein and lipid. The changes in protein conformation and the peroxidation of polyunsaturated lipids mutually promote each other’s oxidation process.

The impact of pressure-shift freezing on the three-dimensional network structure and properties of myofibrillar proteins in surimi gel derived from freshwater fish

Freezing treatment can prolong the shelf life of surimi products, but it will lead to deterioration of surimi gel quality. This study compared the effects of three different processing methods — non-freezing processing (control), conventional air freezing (CAF), and pressure-shift freezing (PSF) — on the three-dimensional (3D) network structure of grass carp surimi gel. After PSF treatment, the pores in the 3D gel network structure were denser compared to the control group which facilitates interaction of water and network structure. Furthermore, the ultraviolet and fluorescence spectral analysis indicated that PSF treatment mitigates the decline in stability of the tertiary structure of myofibrillar protein (MP) during freezing. The microstructure of MP showed that PSF treatment promotes the cross-linking of MP to form protein aggregates and then promotes the gelation of MP. Industrial relevancePSF can increase the commodity value of low-value freshwater fish products and has potential in the development of new products of surimi gels. This study reported a novel idea and theoretical basis for the application of PSF technology in the frozen food and aquatic product processing industry.

Effects of plasma-activated slightly acidic electrolyzed water on salmon myofibrillar protein: Insights from structure and molecular docking

The present study investigated the impact of plasma-activated water (PAW), slightly acidic electrolytic water (SAEW) and plasma-activated slightly acidic electrolytic water (PASW) treatment on myofibrillar protein (MP) in salmon fillets. Additionally, the interaction mechanism between myosin and reactive oxygen species was explored by molecular docking. Compared with the control group (719.26 nm), PASW treatment group exhibited the smallest particle size (408.97 nm). The PASW treatment exhibited efficacy in reducing MP aggregation and inhibiting protein oxidation. In comparison with other treatments, PASW treatment demonstrated a greater ability to mitigate damage to the secondary and tertiary structures of MP. O3 and H2O2 interact with myosin through hydrogen bonding. Specifically, O3 interacts with Lys676, Gly677, and Met678 of myosin while H2O2 binds to Thr681, Asp626, Arg680, and Met678. This study offers novel insights into the impact of PASW on MP, and provides a theoretical foundation for its application in aquatic product processing.

Changes in properties of myofibrillar protein and myofibrillar protein gel from freshwater fish after low-temperature and high-pressure collaborative treatment

This study investigated the effects of low-temperature and high-pressure collaborative and conventional air freezing (CAF) on myofibrillar protein (MP) characteristics from grass carp. Turbidity, solubility, and particle size analysis showed that the pressure shift freezing (PSF) treatment could inhibit the formation of large MP aggregates to a certain extent during freezing. Chemical interaction studies unveiled that PSF treatment not only mitigates damage to the inherent structure of MP during freezing but also enhances its crosslinking ability. Microstructure analysis revealed a densely woven fibrous protein network structure within the MP gel in the PSF group. MP gel with fiber shape network structure in the PSF group exhibited stronger water-holding capacity and mechanical properties compared to the CAF group having an incomplete protein network structure. This suggests that the combined application of low-temperature and high-pressure treatment holds promising potential for utilization in the surimi gel processing industry and aquatic products processing.Industrial relevance: The quality and safety of food are closely related to the commodity value of food. Combined low-temperature and high-pressure treatment can enhance the commodity value of low-value freshwater fish products and has potential in surimi gel new product development. This study provides theoretical guidance for high-pressure and low-temperature collaborative processing and industrial production of related aquatic products.

Control of multi-energy drying system: Optimal weighted combination prediction of moisture content and fuzzy compensation of wind speed

In order to monitor the moisture content accurately and improve the drying uniformity of the same batch of materials, an online moisture monitoring approach based on optimal weighted combination model (OWCM) was developed, and a fuzzy control strategy of wind speed compensation was established for multi-field coexistence. The Human Machine Interface (HMI) and remote monitoring modules are designed, which can automatically obtain, view and store environmental parameters on site and mobile devices. The system was loaded into a kelp drying equipment, and moisture content prediction and drying uniformity verification tests were conducted respectively. The results showed that Root Mean Square Error (RMSE) and Mean Absolute Error (MAE) of the OWCM are 0.022 and 0.019, the prediction accuracy was better than that of single model and average weighted combined model (AWCM). The drying time difference between the front and back of the same batch of kelp was shortened from 1 ∼ 1.5 h to 0 ∼ 0.5 h. This study provides theoretical and technical support for the synergistic utilization of multiple energies and the research and development of aquatic products processing equipment.

Research on Expansion of the Export Paths of Developing Aquatic Products in Hainan Province

Hainan Province is rich in marine resources, and the marine economy is one of the exceptional advantages of Hainan Province's economic development. As the eleventh free trade zone opened by China, Hainan Province, as a province supported by the double policies of special economic zone and free trade zone, should fully harness its strengths, and adopt scientific and correct development strategies to accelerate the construction pace of aquatic products’ export industry. At present, aquatic products in Hainan Province are mostly exported for sale in the form of primary agricultural products, developing marine culture technology is needed, otherwise it will lose its development force in the face of the red line of marine fishing. Furthermore, the lack of fine deep processing of aquatic resources has become the weakness of Hainan Province in the international market competition. Therefore, we should step up efforts to of Hainan Province in the construction of aquatic products’ export industry, establish and perfect a complete aquatic products’ export industry, develop and improve the upstream and downstream industries of Hainan Province's aquatic products export and give support to the aquatic products industry, and increase the research efforts on the fine deep processing of aquatic products and other related application technology.

Ultrasound‐assisted chlorogenic acid‐grafted chitosan soaking of sea bass (Lateolabrax japonicus) fillets to reduce protein oxidation and maintain gel properties

AbstractThe perishability of aquatic products is a challenge for the processing of aquatic products, so it is better to choose suitable preservatives to prevent the degradation of proteins and the fission of their gel properties. Thus, this study investigated the effects of ultrasound‐assisted chlorogenic acid grafted chitosan (GUA) soaking of sea bass (Lateolabrax japonicus) fillets on protein oxidation and gelation properties. The results showed that GUA could reduce the formation of protein carbonyls and maintain Ca2+‐ATPase activity. Intrinsic fluorescence intensity (IFI) and SDS‐PAGE results demonstrated that GUA stabilized the tertiary structure of protein and inhibited protein degradation. Interestingly, ultrasound attenuated the protein aggregation induced by the use of chitosan‐grafted‐chlorogenic acid (CS‐g‐CA), which has good particle size during storage. Meanwhile, GUA treatment endowed the gel with a dense network microstructure, increased water holding capacity (WHC), reduced water mobility, and improved MP gel color as well as textural properties.

Occurrence, removal, and risk assessment of emerging contaminants in aquatic products processing sewage treatment plants.

Emerging contaminants (ECs) in aquatic environments have attracted attention due to their wide distribution and potential ecotoxicities. Sewage treatment plants (STPs) are proven to be the major source of ECs in the aquatic environment, while there remains insufficient understanding of the removal and risk assessment of ECs in STPs. Here, we clarified the degradation and risk impact of 13 ECs in two aquatic product processing sewage treatment plants (APPSTPs) along the southeast coast of China. The concentrations of ECs followed the order: endocrine-disrupting chemicals (1877.85-15,398.02ng/L in influent, 3.37-44.47ng/L in effluent) > > sulfonamide antibiotics (SAs, 75.14-906.19ng/L in influent, 1.14-15.33ng/L in effluent) > pharmaceutical and personal care products (PPCPs, 44.47-589.93ng/L in influent, 2.54-34.16ng/L in effluent) ≈ fluoroquinolone antibiotic (54.76-434.83ng/L in influent, 10.75-32.82ng/L in effluent) > other antibiotics (16.21-51.96ng/L in influent, 0.68-6.17ng/L in effluent). Moreover, the concentrations of PPCPs (decreased by 55.33-87.65% in peak fishing season) and antibiotics (increased by 44.99% in peak fishing season) were affected by fishing activities. In particular, the sequencing batch reactor (SBR) process had a better removal effect than the anaerobic-anoxic-oxic (A2/O) process on the treatment of some contaminants (e.g., norfloxacin and nonylphenol). Risk evaluations of ECs demonstrated that nonylphenol and SAs were at high- and low-risk states, respectively. Overall, our results provide important information for the degradation treatment of ECs, which is essential for pollutant management policy formulation.

Intelligent pulsed ultraviolet c radiation sterilization system: A cleaner solution of raw ready-to-eat aquatic products processing

The sterilization of raw ready-to-eat aquatic products is a crucial method for ensuring their safety for consumption after production. However, achieving intelligent decision-making and higher sterilization efficiency remains a technical challenge. In this paper, an intelligent ultraviolet c radiation (UVC) pulse sterilization system for raw ready-to-eat aquatic products processing lines is presented. The objective of intelligently classifying and grading aquatic products in an automated production line and then sterilizing them is attained. On the basis of the thermal radiation perspective factor method, an irradiation prediction model for the columnar pulsed UVC field is developed, and an automated decision model for the UVC sterilization level is developed in conjunction with the hierarchical analysis method. Automatic control of the UVC lamp is achieved with precision. Using a combination of direct measurements and simulation calculations, the accuracy of the prediction structure is verified. In addition, the system's key model, the UVC intensity decision model, was evaluated, and the results indicated that the decision model had an error rate of 13.3% in the sterilization of raw ready-to-eat aquatic products and that the system's sterilization rate could reach approximately 95%. Additionally, the economics of implementation and overall performance of the sterilization system were evaluated and determined to be effective in reducing spoilage rates and human resource losses, thereby promoting sustainable and clean production in the raw food fish processing industry.

Overview of research progress on new processing technologies for aquatic products

China is rich in aquatic resources and the aquatic processing industry is developing rapidly, and the market potential of products produced using various aquatic raw materials is huge. The socio-economic development and the improvement of people's consumption level have put forward higher requirements for aquatic products, which further promote the technological innovation of related processing. The article classifies aquatic products into six categories: fish, shellfish, algae, crustaceans, echinoderms and cephalopods, and introduces the technological innovations and applications in freezing and preservation, sterilization, and by-product utilization in recent years, respectively, to provide reference for the continued development of aquatic products processing industry in the future.

Surimi freshness monitoring of 4D printing material with anthocyanin

This study proposed a new idea about 3D printing. It provided a feasible attempt for the application of 3D printing in the preservation and processing of aquatic products. Surimi is a kind of food rich in protein and easy to deteriorate. We tried to add xylo-oligosaccharide and CaCl2 to surimi, which improved twice gel strength and quadruple hardness of surimi. It is difficult to detect deterioration during refrigeration. We have designed a gel that can be wrapped on surimi through a dual nozzle 3D printer. The gel was in direct contact with surimi. The gel made of 5% carrageenan, 5% xanthan gum and 1% hydroxymethyl cellulose would change color with the change of pH of surimi after wrapping the surimi. Because anthocyanins have different color characteristics at different pH, the pH of surimi can be known through color change.

Development and evaluation of an intelligent UVC sterilization system for raw aquatic food production

AbstractRaw aquatic food is regarded as an important source of proteins. However, the presence of various bacteria can increase the risk of disease in humans. As a result, a crucial step in the processing of aquatic products is the disinfection of raw aquatic food. An intelligent ultraviolet c radiation (UVC) sterilization system was established and evaluated in this study. On the automated production line, the UVC lamp's sterilization intensity can be automatically adjusted to achieve intelligent sterilization of the various aquatic product categories. The system was implemented and evaluated for oyster surface sterilization experiments in the production line. The quality indicators of oysters, such as volatile salt nitrogen content and aerobic bacterial count, were measured before and after sterilization. The average sterilization rate of the intelligent system is 96.4%. The results showed that the system had an excellent sterilization effect and improved the shelf life of aquatic products.

Legacy and novel perfluoroalkyl substances in raw and cooked squids: Perspective from health risks and nutrient benefits

Perfluoroalkyl substance (PFAS) existed ubiquitously in the environment and could be ingested unconsciously with food which posed a disease risk to human health. Swordtip squid (Uroteuthis edulis) is one of the most popular and highly consumed seafood worldwide, with wide distribution and abundant biomass. Therefore, it is of great importance to the health of the public by reducing the health risks of squid consumption while preserving the benefits of squid to humans. In this study, the PFAS and fatty acids in squids were tested from the southeast coastal regions of China, a major habitat for squids. Relative higher concentrations of PFAS in squid were found in the subtropical zone of southern China (mean: 15.90 ng/g·dw) compared to those of the temperate zone of northern China (mean: 11.77 ng/g·dw). The digestive system had high tissue/muscle ratio (TMR) values, and the pattern of TMR among the same carbon-chain PFAS was similar. Cooking methods have a significant contribution to eliminating PFAS (in squids). PFAS were transferred from squids to other mediums after cooking, so juice and oil should be poured out to minimize PFAS exposure into body. The result showed that squids can be regarded as a healthy food by health benefits associated with fatty acids. Estimated daily intake (EDI) had the highest level in Korea via consuming squids through cooking processes compared with other countries. Based on the assessment of the hazard ratios (HRs), there was a high exposure risk of perfluoropentanoic acid (PFPeA) via taking squids for human health. This research provided the theoretical guidance of aquatic product processing in improving nutrition and reducing harmful substances.

Design and research of shrimp automatic processing equipment

In view of the lack of shrimp deep processing equipment in my country's aquatic product processing industry, this paper takes Penaeus vannamei (hereinafter referred to as shrimp) as the research object. and other key technologies to carry out research, design and develop a new type of shrimp peeling processing equipment. In order to realize the automatic processing of shrimp shell and meat separation, simplify the processing process, reduce manufacturing and production costs, and further improve the economic benefits of shrimp product processing and production.