The global population growth has intensified food security challenges, making aquaculture a crucial source of aquatic food. Rising costs and limited fish meal availability have prompted the exploration of alternative protein sources for aquafeeds. While plant-based ingredients are used, they face issues like low protein content and palatability. Fish silage, created from fish waste, emerges as a sustainable and cost-effective alternative. It is produced by adding acids or lactic acid bacteria to fish waste, resulting in a nutrient-rich mixture beneficial for animal diets. This review focuses on promoting sustainable aquaculture practices by evaluating the benefits and drawbacks of fish silage and highlighting emerging trends in this area.
Introduction
Aquatic foods are essential for food security and nutrition, recognized for their high protein content and unique micronutrients. By 2020, global per capita consumption of aquatic food reached 20.2 kg, a significant increase from 9.9 kg in the 1960s, with projections suggesting further growth to 21.4 kg by 2030. This rising demand has propelled aquaculture, which produced a record 122.6 million tonnes in 2020, but it faces challenges such as high feeding costs and reliance on fish meal and fish oil. These ingredients, primarily sourced from wild fish, are crucial for aquaculture but their production is energy-intensive and economically challenging.
The industry is shifting towards reducing fish meal and fish oil in feeds due to supply and price fluctuations. Alternative protein sources are necessary for the sustainability of aquaculture. While plant-based ingredients have been explored, they present challenges such as inadequate protein content and competition with human food resources. Insect meals and food waste offer promising alternatives, with bioconversion and biotransformation methods enhancing their utility in aquafeeds.
Animal-based proteins, particularly poultry by-product meal, are viable alternatives, though they may lack certain essential amino acids. Fermentation processes can improve the nutritional quality of both plant and animal protein sources. Additionally, fish waste from processing industries can be preserved through ensiling, producing fish silage, a cost-effective and nutritious feed ingredient.
Fish silage, rich in essential amino acids, has gained attention for its high nutritional value and has been successfully integrated into livestock diets, improving growth rates and health. Its production parameters significantly influence its quality, and proper storage is crucial to maintain its nutritional properties. Overall, fish silage represents a sustainable alternative to traditional fish meal, contributing to the nutritional needs of aquaculture and livestock while addressing environmental concerns.
2. Ensiling Technology of Fish Waste
This document provides a comprehensive summary of the ensiling technology applied to fish waste, detailing the types of fish waste, the processes involved in fish silage production, and the implications for animal feed. Fish waste, often comprising parts of the fish not suitable for human consumption, presents significant environmental challenges when not repurposed. The document outlines the methods of converting fish waste into valuable fish silage, which is rich in nutrients and beneficial for animal feed, while also addressing potential risks associated with biogenic amines and lipid oxidation.
v Overview of Fish Waste
Fish waste includes various discarded parts of fish, such as heads, tails, scales, bones, viscera, and skin, as well as fish unsuitable for sale. Approximately 20-80% of fish caught results in waste, influenced by processing methods and fish species. The waste generated poses environmental issues and incurs costs related to disposal.
v Fish Silage Production
Fish silage production is an effective biotechnological approach to repurpose fish waste. This low-energy process transforms fish waste into a nutrient-rich liquid through the action of proteolytic enzymes during milling and homogenization. Two primary methods exist for producing fish silage: acidified fish silage, which uses acids to lower pH and prevent spoilage, and fermented fish silage, which relies on anaerobic microbial fermentation.
Key Factors in Silage Production
The success of fish silage production depends on various factors, including:
- Type and quality of raw materials
- Acids used and their concentrations
- Microbial strains for fermentation
- Environmental conditions (temperature, pH, moisture)
An optimal pH of 3.5 to 4.0 and temperatures between 5 to 40 °C are crucial for effective enzymatic degradation.
v Nutritional Benefits and Digestibility
Fish silage is rich in hydrolyzed proteins and micronutrients, making it highly digestible for animals. Studies indicate that fish silage may be more digestible than traditional fish meal due to the presence of short-chain peptides and free amino acids. However, caution is warranted regarding biogenic amines, which can form during fermentation and pose health risks to animals.
v Lipid Oxidation Concerns
Fish waste contains crude lipids that are prone to oxidation, particularly in acidic conditions. This oxidation can reduce nutritional value and sensory quality. To mitigate lipid oxidation, antioxidants such as ethoxyquin and butylated hydroxytoluene (BHT) are recommended.
Fish silage production offers a sustainable solution for managing fish waste while enhancing animal feed quality. However, careful consideration of the fermentation process, microbial strains, and antioxidant use is essential to maximize the benefits and minimize risks associated with fish silage.
2.1. Acidified Fish Silage Production
Acidified fish silage production is an effective and economical method for preserving fish processing waste, suitable for various operational scales. The process involves adding organic or inorganic acids, typically at a concentration of 2–3% (w/w), to homogenized fish waste, which lowers the pH to 4 or below. This acidification prevents the growth of pathogenic and spoilage microorganisms. The choice of acid is influenced by cost and availability, with organic acids like formic acid being favored for their ability to produce less acidic silages that do not require neutralization before use. The subsequent autolytic liquefaction, driven by endogenous proteolytic enzymes, primarily occurs in fish waste containing stomach viscera, leading to the hydrolysis of proteins into free amino acids and short-chain peptides, while lipids are broken down into fatty acids.
The application of organic acids in fish silage not only serves as a preservation method but also has potential benefits for animal health and growth in aquaculture. Short-chain organic acids, such as formic acid, are being investigated as growth promoters in animal feeds, particularly as alternatives to non-therapeutic antibiotics. These acids exhibit antimicrobial properties and can positively influence gut microbiota, while also enhancing the absorption of essential minerals. Formic acid in fish silage hydrolysate may improve fish growth and health, especially under adverse microbiological conditions. However, the effectiveness of these acids can vary based on several factors, including the type of acid, its application form, and environmental conditions. Limitations exist regarding the amount of formic acid that can be included in fish feed without adverse effects, although recent studies suggest that amino acids and peptides from acidified silage could enhance the welfare of farmed fish during stressful periods.
2.2. Fermented Fish Silage Production
Fermented fish silage is created through the fermentation of fish waste using lactic acid bacteria (LAB) such as Lactobacillus and Lactococcus, combined with carbohydrate sources like molasses or vegetable waste. This anaerobic fermentation process produces lactic acid, which lowers the pH to around 3.5–4.0, inhibiting pathogenic microorganisms and enhancing the action of proteolytic enzymes that hydrolyze fish waste. The dominance of lactic acid in the silage not only preserves it but also improves its quality, making it a valuable product for animal feed. The careful selection of LAB strains, particularly those isolated from the same source, is crucial for effective fermentation, although the process requires meticulous monitoring.
The fermentation of fish silage significantly boosts its nutritional value, increasing crude protein content and enhancing the stability of fats, which is beneficial for animal feed. Studies have shown that incorporating fermented fish silage into animal diets can improve growth performance and intestinal health, making it a viable alternative to traditional protein sources like fish meal and soybean meal. Additionally, innovative approaches, such as using lemon peel during fermentation, have been shown to enhance protein levels and protect LAB from low pH conditions. The digestibility of proteins from fermented fish silage is also higher than that of acidified silage, attributed to the breakdown of proteins into short peptides and free amino acids during fermentation, which serve as nutritious stimulants for various animal species.
2. 3. Fish Silage Oil Production
Fish silage oil, extracted from fish waste, has emerged as a significant feed ingredient for aquaculture, demonstrating effective recovery methods through the ensiling process. Research indicates that fermentation can recover over 85% of the oil from fish viscera, with studies comparing silages prepared through acidic and fermentation processes. Notably, fermented fish viscera silage has shown a higher potential for oil extraction, while acidified silage serves as a valuable protein source for animal feed. Investigations into the lipid quality and fatty acid compositions of oils derived from these silages reveal that fermented options outperform their acid-preserved counterparts, suggesting their viability as additives for both animal and human diets.
The potential of fish silage oil as a feed ingredient is further underscored by its rich content of essential fatty acids, particularly polyunsaturated fatty acids (PUFAs), making it a cost-effective alternative to traditional fish oil in aquaculture. This approach not only enhances the nutritional profile of fish feeds but also promotes sustainability by reducing reliance on wild-caught fish. By incorporating fish silage oil into aquaculture practices, the industry can benefit from a more sustainable and nutrient-rich feeding strategy, aligning with the growing demand for environmentally responsible aquaculture solutions.
3. Nutritional and Health Benefits of Fish Silage
Fish silage is a valuable product made from various fish materials, including whole fish and fish waste. Its nutritional quality is influenced by the type and freshness of the raw materials, with typical compositions showing around 80% moisture, 15% protein, and less than 4% ash. Research indicates that the nutritional profile of fish silage is closely tied to the freshness and composition of its ingredients. Studies have shown that fish silage can offer high protein digestibility and essential amino acids, making it a promising alternative protein source in aquafeeds. However, factors such as protein hydrolysis and lipid oxidation can negatively impact its nutritional stability.
3.1. Protein Content of Fish Silage
Research has demonstrated varying protein content in fish silage, with studies showing increases in crude protein during fermentation. For instance, Banze et al. (2017) found that acidified fish viscera silage had a crude protein content of 669.40 g/kg after 30 days. However, prolonged ensiling can lead to protein loss due to excessive hydrolysis, which can reduce essential amino acids.
3.2. Amino Acid Profile of Fish Silage
The amino acid profiles of fish silage often surpass those of fish meal, particularly in essential amino acids. Banze et al. (2017), noted that fish viscera silage contained higher amounts of essential amino acids compared to fish meal, with glutamic acid being prevalent. This high concentration can enhance the immune response in animals, although low pH levels may compromise the stability of certain amino acids like tryptophan.
3.3. Lipid Content and Fatty Acids Composition of Fish Silage
Fish silage is a source of beneficial fatty acids, including monounsaturated and polyunsaturated fatty acids, which are important for fish health. Studies have shown that fish viscera silage contains significant levels of n−3 fatty acids, such as EPA and DHA. The fatty acid composition can vary, with some silages showing higher unsaturated fatty acids, which are favorable for aquafeed formulations. Additionally, fish silage oil has been found to be a cost-effective alternative to traditional fish oils, improving production performance and gut health in tilapia.
3.4. Ash Content of Fish Silage
The ash content in fish silage is another important parameter, this ash content of fish silages depends on the composition of the raw material and can range from 11.9% to 21.5%. Generally, the ash content can influence the overall mineral profile and nutritional value of the silage. High ash content is undesirable in fish diets, as some mineral needs can be met directly through the water in the aquaculture system. Fish silage produced from fish viscera (intestine, stomach, liver, pancreas, swimming bladder, kidney, spleen, gonads), without bones, fins, and heads, had low mineral content. This low mineral content in the fish viscera silage is considered a positive aspect, as excess minerals in fish diets are undesirable
3.5. Microbial Characteristics of Fish Silage
Tropea et al.(2021) emphasized the necessity of rapid pH reduction to ensure microbial hygiene and product quality in aquafeed. Their findings indicated a significant decrease in total coliform counts during fermentation, with complete absence after 96 hours, likely due to bacteriocins produced during lactic acid fermentation and environmental acidification. This reduction enhances bioconservation against harmful microorganisms, resulting in a final product rich in beneficial microbes. Banze et al. confirmed the absence of significant microbial growth in both raw materials and the produced silage, underscoring the quality of fish viscera and the role of acetic acid in inhibiting microbial proliferation.
3.6. Biogenic Amines
Biogenic amines, which are low-molecular-weight products of amino acid decarboxylation during fermentation, can pose toxicity risks in fermented foods. Proper management of raw materials and hygiene practices can control their levels. Banze et al. observed an increase in various biogenic amines during fish silage production, attributing this to high ambient temperatures. Özyurt et al. identified several predominant biogenic amines and concluded that fermented fish silage could serve as a potential protein source and probiotic ingredient in animal feed.
3.7. Protein and Lipid Digestibility of Fish Silage
Many studies reported that the apparent digestion coefficients for fish viscera silage were comparable to fish meal, with silage showing higher dry matter digestibility due to acid hydrolysis. The high lipid content in fish viscera silage resulted in a superior lipid digestion coefficient compared to other oils. This digestibility is crucial for the nutritional value of fish diets, particularly for tambaqui juveniles.
3.8. Beneficial Effects of Fish Silage on Animal Health and Feed Quality
Organic acids in fish silage possess antibacterial properties and act as natural preservatives. Kuley et al. found that selected lactic acid bacteria (LAB) strains produced significant amounts of organic acids during fermentation, enhancing food safety and quality. Fish diets supplemented with organic acids showed improved growth performance and feed utilization. Additionally, peptides and free amino acids from protein hydrolysis in fish silage can stimulate non-specific immunity in aquatic animals. Research indicates that fermented diets can enhance gut morphology and nutrient absorption in fish, leading to better overall health.
Organic acids present in fish silage, such as lactic, acetic, and propionic acids, exhibit antibacterial properties that enhance food safety and quality. Studies have shown that diets supplemented with organic acids lead to improved feed intake and growth performance in both terrestrial livestock and aquaculture animals. Additionally, fish viscera silage has been found to stimulate non-specific immunity in fish species, providing essential dietary protein and amino acids that positively influence growth and immune response. The structural integrity of the gut is crucial for nutrient absorption, and research indicates that fermented diets can enhance gut morphology, leading to better health outcomes. Fermented fish silage has shown to improve the intestinal health of both fish and broiler chickens, suggesting its potential as a viable protein source in animal diets. Furthermore, the antimicrobial properties of silage oil contribute to improved feed hygiene and reduced microbial competition in the gastrointestinal tract, further enhancing the nutritional benefits of fish silage.
4. Utilization of Fish Silage in Aquaculture Feeds
The utilization of fish silage in aquaculture feeds presents a promising avenue for enhancing the nutritional value of diets for various fish and crustacean species. Fish silage can be incorporated as acidified or fermented silage, protein hydrolysate, or in combination with plant-based ingredients, offering advantages such as cost-effectiveness and sustainability. Research indicates that moderate inclusion levels of fish silage can improve growth performance in species like Japanese sea bass and Atlantic salmon, while also providing essential amino acids and nitrogen compounds that are often lacking in plant-based feeds. Studies have shown that fish silage can replace significant portions of fish meal without adversely affecting growth, with some formulations demonstrating improved digestibility and feed efficiency.
However, it is essential to carefully manage the inclusion levels of fish silage in aquafeeds, as excessive amounts can lead to negative outcomes, including reduced growth performance and increased mortality rates. Research has identified an upper limit for fish silage incorporation, beyond which detrimental effects on fish health and growth may occur. For instance, high replacement levels of fish meal with fish silage have been linked to metabolic disruptions and stress in fish. Overall, while fish silage and its derivatives offer a sustainable and nutrient-rich alternative to traditional fish meal, their application in aquaculture feeds must be optimized to ensure the health and growth of farmed species.
5. Fish Silage as Feed Ingredients: Advantages, Challenges, and Considerations
Fish silage, derived from fish waste or discarded fish, is gaining recognition as a valuable ingredient in aquafeeds. This document explores the advantages and challenges associated with fish silage, emphasizing its potential as a sustainable and cost-effective feed ingredient while addressing the complexities involved in its production and use.
5.1. Advantages of Fish Silage
1. Waste Utilization and Environmental Sustainability: Fish silage repurposes fish waste and discarded fish, providing an environmentally friendly disposal method that mitigates the impact of poor waste management.
2. Cost-Effectiveness: As a more affordable alternative to traditional fish meal, fish silage can significantly reduce feeding costs, making it an economically viable option for aquaculture.
3. Nutrient-Rich Feed Ingredient: Fish silage is rich in hydrolyzed proteins and lipids, offering essential nutrients that promote animal growth and health. Its digestibility is often superior to that of conventional fish meal.
4. Improved Feed Conversion: The use of fish silage can enhance feed conversion rates, leading to more efficient biomass production and a lower environmental footprint.
5. Simple and Accessible Process: The production of fish silage is straightforward and less costly compared to traditional fish meal production, making it accessible for small-scale operations.
5.2. Challenges and Limitations
1. Natural Compositional Variability and Quality Control: Variability in raw materials and processing methods can lead to inconsistent quality and nutritional value in fish silage.
2. Accessibility and Availability of Raw Materials: The seasonal availability of fish waste can limit the supply chain stability for fish silage production.
3. Transport and Storage Challenges: High water content in fish silage complicates transportation and storage, necessitating specialized conditions to maintain quality.
4. Processing Costs and Energy Consumption: While ensiling is generally cost-effective, advanced processing methods may increase energy consumption and overall costs.
5. Processing Time: The production process can be time-consuming, which may affect efficiency.
6 . Microbial Contamination: Improper storage can lead to microbial contamination, impacting safety and shelf life.
7. Biogenic Amine Formation: The fermentation process can lead to biogenic amine formation, which poses risks to feed safety and fish health.
5.3. Considerations for Improvement
1. Stable Supply of Raw Materials: Ensuring a consistent and quality supply of fish waste is essential for commercial viability.
2. Separation and Processing of Different Fish Species: This can enhance product consistency and quality, particularly in relation to regulatory compliance.
3. Coordinated Collection and Transport Network: A well-organized system for collecting and transporting raw materials is crucial for maintaining quality.
4. Advanced Processing Techniques: Utilizing methods like spray drying and encapsulation can improve product quality and handling.
5. Optimization of the Fermentation Process: Monitoring and optimizing fermentation conditions can help control biogenic amine formation and ensure product safety.
6. Addressing Regulatory Requirements: Compliance with quality standards and legislation is necessary for successful fish silage production in developed markets.
These considerations underscore the need for a comprehensive approach to enhance the quality and scalability of fish silage as a feed ingredient in aquaculture.
6. Emerging Technologies for Enhancing the Nutritional Value and Efficiency of Fish Silage Production
Fish silage, while a valuable feed component, faces challenges due to its high water content, which complicates transportation and storage. Traditional drying methods are often costly and environmentally detrimental, prompting the exploration of more sustainable alternatives such as spray drying encapsulation, microencapsulation of bioactive compounds, and refractance window drying technology.
Overview of Fish Silage Challenges
Fish silage is typically produced in a liquid state, which presents logistical challenges due to its high water content. This not only increases transportation and storage costs but also limits its direct application in feed formulations. Moreover, the necessity for airtight storage to prevent spoilage from aerobic pathogens adds to the complexity of handling fish silage.
Advantages of Drying Fish Silage
Drying fish silage can enhance its value by improving handling, reducing packaging and transportation costs, controlling microbial growth, and increasing protein concentration. However, conventional drying methods are often energy-intensive and environmentally harmful. Solar drying presents a more sustainable option, though it has limitations such as longer processing times and potential microbial contamination.
6.1. Spray Drying Encapsulation
Spray drying encapsulation is emerging as a promising technique for transforming liquid fish silage into powdered form. This method involves spraying the liquid into a hot gas stream, allowing for rapid moisture removal while preserving the nutritional integrity of the product. The use of maltodextrin as a carrier material is common due to its cost-effectiveness and protective qualities, although its low emulsifying capacity can be a drawback. Combining maltodextrin with other biopolymers may enhance microencapsulation effectiveness. Additionally, spray drying can protect sensitive compounds like omega-3 fatty acids from oxidation, making it a valuable method for producing high-quality fish silage.
6.2. Microencapsulation of Bioactive Compounds
Microencapsulation technology is increasingly utilized in animal nutrition to protect sensitive compounds and enhance their bioavailability. This method is particularly beneficial for lactic acid bacteria (LAB) in fish silage production, as it helps maintain their viability under harsh conditions. Research on Weissella paramesenteroides has shown that encapsulation can significantly improve the survival of LAB during fermentation, thereby enhancing the quality and safety of fish silage.
6.3. Refractance Window Drying Technology
Refractance window (RW) drying is a nonthermal dehydration technique that offers several advantages over traditional methods. By utilizing a combination of heat transfer modes and the principle of light refraction, RW drying effectively preserves the nutritional quality of products while achieving rapid drying times. Studies indicate that RW drying can efficiently reduce moisture content in fish silage while maintaining its color, flavor, and nutritional properties. The method is cost-effective and energy-efficient, making it a viable option for the drying of fish silage.
7. Innovative Approaches to Sustainable Protein Alternatives through Waste Valorization
The focus is on utilizing by-products from agricultural processes, such as fruit and vegetable biomass, to create eco-friendly aquafeeds. Techniques like fermentation are highlighted for their potential to convert waste into valuable animal feed, thereby promoting a closed-loop economy and reducing environmental impact.
The aquaculture sector is increasingly exploring sustainable protein sources to replace traditional fish meal and plant-based ingredients. A promising approach involves repurposing agricultural waste, such as fruit and vegetable biomass, which can serve as a sustainable protein source for aquafeeds. This method not only reduces reliance on land-based feed production but also minimizes waste, aligning with eco-friendly aquaculture practices.
Fermentation of agri-food waste is identified as a key technique for transforming waste materials into high-value products, including animal feed. This environmentally friendly and cost-effective method addresses issues of digestibility and contamination in waste. Tropea et al. demonstrated a fermentation process that converts non-sterilized fish waste and lemon peel into a high-protein supplement for aquaculture, enriched with beneficial microorganisms and low spoilage levels.
Additionally, agricultural by-products like apple pomace, rich in fermentable sugars, are being explored for their potential in aquafeed production. Combining apple pomace with marine biomass to create fish silage exemplifies how waste can be valorized, contributing to sustainable raw material utilization.
Munekata et al. (2021) reviewed the valorization of pomaces from juice and olive oil extraction, emphasizing their incorporation into animal feed. The production of silages from fermented pomaces can enhance animal health and growth performance, showcasing the nutritional benefits of this approach.
Panyawoot et al. (2022) investigated the effects of fermented discarded durian peel in the diets of goats. Their findings indicated that fermentation with molasses and Lactobacillus casei significantly improved nutrient digestibility and reduced methane production, demonstrating the viability of using fermented agricultural waste in livestock diets.
8. Utilization of Fish Silage as a Fertilizer
Fish silage serves as an effective fertilizer when it does not meet animal feed quality standards. Its nutrient-rich profile includes nitrogen, phosphorus, potassium, calcium, magnesium, and trace elements, which may be lacking in some industrial fertilizers. The nutrient composition varies based on raw materials, with higher bone content leading to increased phosphorus and magnesium levels. Free amino acids and short peptides in fish silage are readily absorbed by plants, promoting growth and aiding in cellular processes, including pH regulation and stress defense.
Research indicates that applying 2–5% liquid fish silage to irrigation water can yield results comparable to traditional fertilizers. A study by Karim et al. (2015) assessed the effects of different concentrations of fish silage on pak choi growth, revealing that 5% fish silage produced similar outcomes to commercial fertilizers while being more economical.
The study by Gauthankar et al. (2021) further explored the amino acid composition of fish silage from different fish species, noting that fermentation duration significantly influences nutrient content. Indian mackerel silage exhibited higher total and free amino acid levels, suggesting that a 25–30-day fermentation period enhances its value as an organic fertilizer.
Overall, fish silage presents a cost-effective and environmentally friendly alternative to conventional fertilizers, aligning with circular economy principles by repurposing fish waste into valuable agricultural inputs. Further research is necessary to understand the effects of fish species and processing methods on its nutritional profile, ultimately contributing to sustainable farming practices.
9. Conclusions and Future Remarks on Sustainability in Aquaculture
The principles of Blue Growth advocate for sustainable marine resource development and waste reduction, highlighting the importance of repurposing fish waste and discarded fish. By transforming these often-overlooked materials into valuable products such as animal and aquafeed, as well as organic fertilizers, the industry can significantly enhance its sustainability efforts. The use of organic acids, specifically formic acid, has emerged as a cost-effective and scalable technology that not only preserves fresh fish raw materials but also contributes to the production of fish silage and protein hydrolysate, which are beneficial for animal and fish feed.
The future of aquaculture appears promising with the incorporation of fish silage into aquafeeds, as it presents a unique opportunity for protein replenishment while enhancing the nutritional quality of feeds. Fermentation processes involved in producing fish silage improve nutrient availability and digestibility, while also fostering beneficial microorganisms that positively influence the health and growth of aquatic species. This approach aligns with the principles of a circular economy by repurposing food waste and by-products, thereby reducing the environmental footprint of aquaculture. The integration of fish silage into feed formulations not only supports sustainability but also addresses the growing demand for alternative protein sources in the industry.
To fully realize the benefits of fermented feed ingredients in aquaculture, ongoing research and development are essential. Advancements in fermentation techniques, optimization of microbial cultures, and thorough nutritional assessments will be vital in enhancing aquafeed formulations. Additionally, exploring the long-term effects of fermented feeds on aquatic organisms, including their impact on gut health, disease resistance, and product quality, remains a critical area for future investigation. As the aquaculture industry continues to evolve towards more sustainable practices, the exploration and implementation of fermented feed ingredients are expected to play a pivotal role in shaping its future.
Source : Maksimenko, A.; Belyi, L.; Podvolotskaya, A.; Son, O.; Tekutyeva, L. Exploring Sustainable Aquafeed Alternatives with a Specific Focus on the Ensilaging Technology of Fish Waste. Fermentation 2024, 10, 258. https://doi.org/10.3390/fermentation10050258
