High-Pressure Processing (HPP) in Organic Systems

High-Pressure Processing (HPP), also referred to as high hydrostatic pressure (HHP) or pascalization, has emerged as one of the most transformative innovations in modern food preservation, particularly for the organic and clean-label food industry. This non-thermal preservation method relies on applying extremely high levels of isostatic pressure, typically between 300 and 600 MPa, to packaged food products in order to inactivate pathogenic and spoilage microorganisms without the need for synthetic preservatives or heat-based pasteurization.

This technological advancement is a direct response to the evolving preferences of health-conscious consumers who demand food products that retain their natural sensory qualities, nutritional integrity, and safety while being free from artificial additives. Organic food systems, governed by stringent regulations that prohibit most chemical preservatives and synthetic processing aids, have found in HPP a unique method that aligns with their foundational principles of naturalness and minimal processing, while also addressing the shelf-life limitations traditionally associated with organic products.

The fundamental principle behind HPP is deceptively simple but scientifically sophisticated. Food items, pre-packaged in flexible and waterproof materials, are inserted into a pressure vessel filled with water, which acts as the medium for transmitting pressure. Pressure is then applied uniformly and instantaneously from all directions through the incompressible water, ensuring that the entire product experiences the same force regardless of its shape, size, or composition.

This uniform pressure inactivates vegetative microorganisms such as Listeria monocytogenes, Escherichia coli, and Salmonella without causing significant heat generation. Since the process is conducted at or near room temperature, thermally sensitive nutrients like vitamin C, folate, and certain polyphenolic antioxidants remain largely intact, unlike in conventional heat treatments that often degrade these compounds. This unique attribute has made HPP particularly valuable for organic products where freshness and nutrient retention are paramount selling points.

The benefits of HPP for organic systems extend beyond nutrient preservation. One of the persistent challenges faced by organic producers is the limited shelf life of their products due to the absence of chemical preservatives such as sodium benzoate, potassium sorbate, and nitrates. For example, fresh organic juices without pasteurization may spoil within 3–5 days, and ready-to-eat organic dips or deli meats may develop microbial spoilage within a week under refrigeration.

HPP can extend the shelf life of such products significantly—cold-pressed organic juices treated with HPP have been shown to maintain microbial safety and sensory quality for 30 to 60 days under chilled storage, while organic deli meats can achieve shelf lives of several weeks without the use of synthetic curing agents. This shelf-life extension not only improves consumer convenience but also has profound implications for reducing food waste across the supply chain, an important consideration for sustainable organic practices.

One of the most important features of HPP in the organic context is its compatibility with clean-label marketing. Because HPP is a physical process rather than a chemical intervention, it does not require the addition of substances that might appear on ingredient lists, allowing organic food brands to maintain short, simple labels composed of familiar, natural ingredients. This transparency resonates strongly with consumers who often interpret clean-label foods as being healthier, less processed, and more trustworthy. Indeed, many companies actively promote HPP under consumer-friendly terminology such as “cold-pressured” or “cold pasteurized,” framing the technology as a natural way to ensure safety and freshness.

From a sensory perspective, HPP preserves the taste, aroma, color, and texture of organic foods far better than traditional pasteurization. Volatile aroma compounds, which are responsible for the fresh scent of fruits and vegetables, are often lost or altered during heat treatments, leading to “cooked” or “caramelized” flavor notes that are undesirable in fresh juices or purees.

In contrast, HPP maintains the volatile profile almost unchanged, resulting in a product that tastes as if it were freshly prepared. In terms of texture, HPP-treated organic seafood retains its delicate firmness, organic plant-based protein products avoid the mushiness that can result from heat treatments, and fresh-cut organic produce maintains a crisp bite for a longer period. These qualities are essential for premium-positioned organic products where sensory appeal justifies higher price points.

Scientifically, the microbial inactivation achieved by HPP is due to the disruption of cellular membranes, denaturation of proteins, and interference with the enzyme systems essential to microbial survival. Vegetative bacteria, yeasts, and molds are particularly sensitive to high pressure, whereas bacterial spores are significantly more resistant. As a result, HPP is highly effective for acidic and refrigerated foods but less suited for low-acid, shelf-stable foods unless combined with other hurdles such as mild heat or natural antimicrobials. For the organic industry, this means HPP works exceptionally well in fresh juices, fruit-based products, fermented vegetables, and chilled ready-to-eat meals but still requires careful formulation considerations for products intended to be stored at ambient temperatures.

Nutritional studies have confirmed the superiority of HPP in preserving bioactive compounds compared to thermal processing. Research on HPP-treated organic carrot juice, for example, has shown retention rates of over 90% for beta-carotene and vitamin C after processing, with minimal changes even after 30 days of refrigerated storage. Similar results have been reported for phenolic compounds in organic berries and antioxidant capacity in green leafy vegetable juices. These findings reinforce HPP’s alignment with the organic principle of delivering food in as close to its natural state as possible, without sacrificing safety.

The environmental footprint of HPP is another area of relevance for organic systems, which often emphasize sustainability. While HPP equipment represents a substantial capital investment and the process consumes energy to generate high pressures, it is generally more energy-efficient than prolonged thermal treatments for equivalent microbial kill levels. Additionally, the water used in HPP systems is typically recirculated within the closed processing loop, reducing waste.

 The extended shelf life enabled by HPP further contributes to sustainability by lowering product losses at retail and in consumer households. However, one environmental trade-off lies in the packaging: the process requires packaging materials that can withstand extreme pressures without compromising seal integrity, and currently, most of these are multi-layer plastics that are not biodegradable. This poses a challenge for organic brands seeking to integrate compostable or bio-based packaging into their products. Research into high-barrier, plant-based, and pressure-resistant packaging materials is underway, and its successful implementation will further enhance HPP’s compatibility with the organic ethos.

Commercial adoption of HPP in organic systems spans diverse product categories. Organic beverage producers use it to stabilize cold-pressed juices, almond milk, and kombucha while retaining fresh flavors. Organic meat and seafood companies apply HPP to sliced turkey, smoked salmon, and ready-to-eat chicken to ensure safety without nitrites or artificial preservatives In organic products that are plant-based and vegan, HPP helps preserve the fresh and minimally processed charm of dips, spreads, and meat alternatives. Even organic baby food brands have embraced HPP to deliver nutrient-rich purees with extended refrigerated shelf life, providing peace of mind for parents who avoid heat-processed jars.

The integration of HPP into the organic supply chain has not been without challenges. The equipment’s high cost, often several million dollars per unit, makes it impractical for many small and mid-sized organic producers to own. Instead, many rely on HPP tolling facilities co-packers who process products for multiple brands. While this makes the technology more accessible, it also adds complexity in terms of logistics, transportation to processing sites, and coordination of packaging requirements. Additionally, HPP does not sterilize food, meaning treated products must still be kept under refrigeration, which necessitates robust cold chain management from production to retail.

From a regulatory standpoint, HPP is widely accepted in the organic sector as it does not involve ionizing radiation, synthetic chemicals, or genetic modification. Both USDA Organic and EU Organic frameworks recognize it as a physical processing method consistent with organic principles. However, product-specific regulations particularly regarding shelf life claims, pathogen testing, and pH requirements must still be adhered to. The acceptance of HPP by organic certifiers has paved the way for its rapid adoption, but continued consumer education is necessary to dispel misconceptions and position the technology as both natural and safe.

Looking ahead, the role of HPP in organic systems is expected to expand as consumer demand for fresh, clean-label products continues to grow.

The combination of food safety, nutrient retention, sensory quality, and extended shelf life makes it a powerful tool for overcoming the constraints traditionally associated with organic foods. Future developments may focus on combining HPP with natural antimicrobial agents such as essential oils or plant extracts to enhance spore inactivation, or integrating it into multi-hurdle preservation systems tailored for ambient-stable organic products. Equally important will be advancements in sustainable packaging solutions that can withstand high pressures without undermining the organic sector’s environmental commitments.

In summary, High-Pressure Processing represents a rare convergence of technological sophistication and natural-food integrity. For the organic industry, it offers a way to maintain safety and extend shelf life without betraying the clean-label promise that lies at the heart of organic branding. While capital costs, packaging sustainability, and spore resistance remain areas for further improvement, the alignment of HPP with the sensory, nutritional, and ethical priorities of organic systems ensures it will remain a cornerstone technology in the sector for years to come. By preserving the essence of freshness while meeting the demands of modern distribution, HPP has become not just a processing method but a strategic enabler for the continued growth and credibility of organic foods in a competitive, quality-driven marketplace.

Modified Atmosphere with Organic Compatibility

Modified Atmosphere Packaging (MAP) with organic compatibility represents a rapidly evolving frontier in clean-label food preservation, where the primary goal is to extend the shelf life of perishable products while maintaining strict compliance with organic food standards. MAP works by altering the composition of gases surrounding the food within a sealed package, most commonly adjusting oxygen (O₂), carbon dioxide (CO₂), and nitrogen (N₂) concentrations to slow down spoilage processes.

While conventional MAP often relies on synthetic or non-organic-compatible materials, organic-compliant MAP seeks to ensure that every aspect of the system from the gas mixtures used to the packaging materials themselves meets regulatory requirements set by certifying bodies such as USDA Organic, EU Organic, and other global standards.

This approach demands innovation in both material science and food preservation technology because organic regulations prohibit the use of certain synthetic additives, require sustainability in material sourcing, and prioritize minimal chemical intervention. As a result, developing MAP systems that align with these principles has become a critical research area for the organic food industry, particularly in the fresh produce, dairy, bakery, and ready-to-eat sectors.

In traditional MAP systems, the role of oxygen reduction is crucial, as lowering oxygen slows oxidative reactions, microbial growth, and enzymatic activity that lead to quality deterioration. However, excessively low oxygen can trigger anaerobic microbial growth or off-flavors, especially in fresh produce. In organic-compatible MAP, the challenge lies not only in optimizing gas ratios for different food types but also in ensuring that gases are sourced and handled in ways that meet organic certification requirements. For example, food-grade CO₂ must be derived from approved sources and must not be contaminated with non-permitted substances during processing or storage.

Additionally, nitrogen, which is used to displace oxygen and reduce oxidative damage, must be produced and purified through organic-compliant processes. These technical requirements increase the complexity of MAP implementation for organic producers, making research into alternative gas generation and purification technologies essential. Furthermore, organic-compatible MAP often integrates natural antimicrobial systems, such as plant-derived essential oils or naturally fermented gases, to boost microbial control without resorting to synthetic preservatives. The synergy between controlled atmosphere and natural antimicrobials can enhance shelf life while ensuring compliance with both clean-label and organic philosophies.

Another significant area of innovation in organic-compliant MAP is the packaging material itself. Conventional MAP frequently uses multilayer films with synthetic barrier coatings such as ethylene vinyl alcohol (EVOH) or polyvinylidene chloride (PVDC), which provide excellent gas barrier properties but are not always permitted in certified organic systems due to their petrochemical origins and non-biodegradable nature. To address this, researchers and industry innovators are developing bio-based, compostable films derived from plant sources such as polylactic acid (PLA), starch, or cellulose, which can still provide the necessary barrier properties while meeting organic and sustainability requirements.

These films are often combined with natural waxes, chitosan, or protein-based coatings to improve moisture and gas barrier performance. Modified permeability is another critical aspect, as films for organic produce need to balance oxygen ingress and carbon dioxide egress to avoid anaerobic conditions while still slowing respiration rates. Advances in nano-structured coatings, derived from natural clay minerals or plant-based nanoparticles, are being explored to enhance barrier properties without compromising compostability or organic compliance. The development of these materials not only extends shelf life but also addresses the increasing consumer demand for plastic-free, eco-friendly packaging solutions.

From a physiological standpoint, MAP for organic produce must be carefully tailored to the respiration rates and metabolic activity of the food product. Fresh fruits and vegetables, for example, continue to respire after harvest, consuming oxygen and releasing carbon dioxide and water vapor. In organic systems, where synthetic chemical coatings and preservatives are avoided, MAP plays an even more critical role in slowing senescence and microbial spoilage. However, because organic produce is often grown without synthetic pesticides, it can have a higher initial microbial load, making precise control of gas composition even more important.

Research has shown that an atmosphere with slightly reduced oxygen (typically 3–5%) and elevated carbon dioxide (3–10%) can significantly extend the storage life of many organic fruits and vegetables without compromising flavor or texture. For example, studies on organic strawberries and leafy greens have demonstrated that organic-compliant MAP can maintain freshness for up to two to three times longer than conventional air storage, provided that the gas ratios and packaging films are correctly matched to the product’s respiration characteristics. For products such as organic cheeses or bakery goods, low oxygen and high nitrogen environments help to inhibit mold growth and oxidation of fats, while maintaining the sensory qualities valued by consumers.

Beyond produce, MAP is increasingly being applied to organic-ready meals, fresh pasta, and minimally processed meats. These categories face particular challenges because organic certification limits the use of common synthetic antimicrobials such as sodium nitrite or sorbates, which are widely used in conventional foods to inhibit spoilage and pathogenic microorganisms. In organic systems, MAP serves as a crucial non-chemical preservation tool, often combined with refrigeration and high-hygiene processing environments to achieve the desired shelf life.

For organic meats, elevated CO₂ concentrations (up to 60–70%) can be used to suppress aerobic spoilage bacteria, while nitrogen fills the remaining headspace to prevent package collapse and oxidative damage. For organic dairy products like soft cheeses, lower oxygen levels and controlled CO₂ can significantly delay mold growth without the need for chemical preservatives. The combination of MAP and vacuum skin packaging (VSP) is also gaining popularity for organic protein products, as it enhances barrier protection and reduces gas exchange, further extending shelf stability.

One of the emerging frontiers in organic-compliant MAP is the integration of active packaging technologies that complement the modified atmosphere. Active packaging involves incorporating natural substances into the packaging material or headspace that interact with the internal atmosphere to maintain optimal conditions. Examples include oxygen scavengers derived from natural iron or ascorbic acid, CO₂ emitters based on natural fermentation processes, and ethylene absorbers made from minerals like zeolite or activated carbon coated with natural potassium permanganate alternatives.

In the context of organic standards, these active components must be sourced from permitted natural origins and must not involve synthetic processing methods. Such active systems can help fine-tune the package atmosphere over time, compensating for the inevitable changes in gas composition caused by product respiration or permeation through the packaging film. This makes it possible to achieve longer shelf life while maintaining compliance and avoiding any compromise in product safety.

Regulatory compliance plays a central role in defining what constitutes an “organic-compatible” MAP system. In the United States, USDA Organic regulations (7 CFR Part 205) do not explicitly prohibit MAP, but they require that all inputs, including gases and packaging materials, meet the National List of Allowed and Prohibited Substances. This means that MAP gases must be food-grade and free of prohibited contaminants, and packaging films must either be made from approved synthetic substances or natural materials.

The European Union’s organic regulation (Regulation (EU) 2018/848) follows similar principles but also places strong emphasis on environmental sustainability, pushing for recyclable or biodegradable packaging wherever possible. In both cases, the combination of MAP with clean-label preservation methods aligns with the broader organic ethos of minimal processing, environmental responsibility, and avoidance of synthetic additives. As a result, organic-compatible MAP is increasingly positioned not just as a preservation method, but as a marketing tool that resonates with consumer expectations for naturalness, transparency, and sustainability.

The consumer perception of MAP in the organic sector is generally positive, especially when the technology is explained as a natural way to keep food fresher for longer without chemicals. However, there remains a degree of skepticism among some organic consumers who associate “modified atmosphere” with industrial processing. This places a responsibility on organic brands to educate their customers about the natural principles of MAP, emphasizing that the gases used are the same as those naturally found in the air and that the method avoids any synthetic preservatives.

Transparency in labeling, such as indicating “packaged in a protective atmosphere,” can help maintain consumer trust. Moreover, when MAP is combined with compostable and plant-based packaging films, it strengthens the sustainability narrative, making it more appealing to environmentally conscious organic consumers.

The future of organic-compatible MAP is closely tied to advancements in both material science and environmental sustainability. As the organic food sector grows and global supply chains expand, the need to maintain quality over longer transportation times will make MAP even more critical. The ongoing development of high-barrier, compostable films; renewable gas sourcing; and bio-based active packaging systems will likely shape the next generation of organic MAP solutions.

Moreover, integrating MAP with other non-thermal preservation technologies, such as high-pressure processing (HPP) or pulsed light, could provide synergistic effects that further enhance safety and shelf life without compromising organic principles. Ultimately, the success of these innovations will depend on balancing technical performance, regulatory compliance, cost-effectiveness, and consumer acceptance—a complex equation that continues to drive research and collaboration across the organic food industry.

Active Packaging with Natural Preservative Release in Organic Foods

Active packaging with natural preservative release is one of the most significant innovations in modern food preservation, particularly for the organic sector where synthetic additives are prohibited, and consumer trust relies heavily on maintaining a clean-label profile. The concept differs fundamentally from conventional packaging by transforming the package from a passive protective barrier into an active participant in maintaining food quality.

Instead of merely preventing external contamination, active packaging interacts directly with the food or the headspace inside the package, releasing natural compounds that help control spoilage organisms, inhibit oxidation, and preserve sensory attributes over time. This technology offers a unique opportunity for organic food producers to bridge the gap between consumer expectations for naturalness and the practical need for longer shelf life and food safety.

The fundamental science behind active packaging with natural preservative release centers on controlled migration. The active agents—antimicrobial, antioxidant, or both—are either embedded within the packaging material or applied as coatings. Over time, and in response to environmental triggers such as moisture, temperature, or pH, these agents are released into the surrounding space or onto the surface of the food. The migration process is carefully engineered to be gradual and sustained, preventing rapid depletion of the active substance and ensuring consistent protection throughout the intended shelf life. In organic systems, these active substances must be sourced from approved natural materials. Examples include plant-derived essential oils (thyme, oregano, cinnamon, rosemary), naturally occurring organic acids (lactic, acetic, citric), fermentation-derived antimicrobials (nisin, natamycin), and antioxidant-rich extracts (green tea catechins, tocopherols, grape seed extract).

A major advantage of embedding natural preservatives into packaging is that it allows the preservative to act where it is most needed: at the food surface. Since microbial growth and oxidation typically begin at this interface, localized delivery is often more effective than incorporating preservatives into the bulk food matrix. For example, in organic cheese production, nisin-containing biodegradable films have been shown to suppress Listeria monocytogenes growth at the surface while maintaining compliance with organic labeling laws. Similarly, rosemary extract-infused PLA (polylactic acid) films have been applied to organic meat cuts, reducing oxidative rancidity without introducing synthetic antioxidants such as BHA or BHT.

One of the most studied categories of natural actives for organic active packaging is essential oils (EOs). Essential oils such as oregano, thyme, cinnamon, and clove have broad-spectrum antimicrobial activity against both Gram-positive and Gram-negative bacteria, as well as antifungal properties against molds and yeasts. In packaging applications, their effectiveness depends heavily on how they are incorporated.

Direct blending into a polymer matrix can result in rapid volatilization, reducing long-term efficacy. To address this, researchers have used microencapsulation and nanoemulsion techniques to trap EO molecules in carriers such as cyclodextrins or lipid nanoparticles. These carriers protect the oils from degradation during film processing and release them gradually under storage conditions. The result is a stable antimicrobial effect without overwhelming the food with strong aromatic notes—an important factor in consumer acceptance.

Other natural preservatives used in active packaging for organic foods include organic acids like lactic acid and acetic acid, which are well known for lowering pH and inhibiting bacterial growth. When immobilized in biodegradable films, these acids can be released slowly to maintain a mildly acidic microenvironment around the product. This method has been particularly effective in packaging fresh organic produce, where mild surface acidification can delay microbial spoilage without affecting taste.

Fermentation-derived antimicrobials such as nisin and natamycin are also highly compatible with organic standards in many regions. Nisin, a bacteriocin made by Lactococcus lactis, works well against Gram-positive bacteria and remains stable across a broad spectrum of pH levels. Natamycin, a natural antifungal agent, is particularly valuable for preventing mold growth in organic cheese, baked goods, and dried fruit. Both can be incorporated into edible coatings or biodegradable packaging films for targeted release.

From a materials perspective, active packaging systems for organic products often employ biodegradable polymers such as PLA, starch-based films, cellulose derivatives, chitosan, or protein-based matrices. These not only align with environmental sustainability goals but can also serve as effective carriers for natural preservatives. Chitosan, in particular, has dual functionality: it acts as a natural antimicrobial due to its polycationic nature and also serves as a matrix for embedding other natural actives. This makes it ideal for packaging organic fresh produce, seafood, and meat. Protein-based films derived from whey, soy, or gelatin can also be enriched with antioxidant plant extracts to protect high-fat organic foods from oxidative deterioration.

Real-world case studies demonstrate the effectiveness of this technology in the organic sector. One notable example comes from a study on organic strawberries packaged with alginate-based films containing oregano oil. The packaging extended shelf life by up to 10 days while maintaining firmness, color, and flavor.

Another application involved organic poultry meat stored in rosemary-extract-infused PLA films, which showed significantly reduced lipid oxidation compared to controls. In organic dairy, biodegradable films containing nisin successfully delayed spoilage in semi-hard cheeses without the need for synthetic mold inhibitors. Even in bakery applications, active packaging containing encapsulated cinnamon oil has proven capable of suppressing mold growth for several extra days under ambient storage conditions.

However, the implementation of active packaging with natural preservative release in the organic sector is not without challenges. One major issue is release rate control—ensuring that the preservative is delivered at a rate that provides effective protection without causing undesirable sensory changes. For example, too much oregano oil release can impart a strong herbal flavor that may not be acceptable to all consumers. Another challenge is the stability of natural actives during packaging production and storage. Many natural compounds are sensitive to heat, light, and oxygen, which means that production methods must be adapted to avoid degradation. This is where encapsulation technologies and cold-processing methods become critical.

From a regulatory standpoint, compliance with organic certification bodies such as USDA NOP in the United States or EU Regulation 2018/848 in Europe is crucial. All active substances must be naturally derived and listed as approved additives for organic food contact applications. Additionally, migration limits set by food safety authorities (such as the European Food Safety Authority or FDA) must be respected, meaning that the amount of preservative migrating into the food must not exceed established safety thresholds. Manufacturers must also provide scientific documentation proving both safety and functional benefit, which often involves conducting migration studies, antimicrobial efficacy tests, and shelf-life trials.

Consumer perception plays a pivotal role in the adoption of this technology. Organic food buyers are generally more skeptical of packaging innovations, fearing hidden chemicals or unapproved additives. Transparency in labeling such as stating “packaged in natural preservative-infused biodegradable film”can help alleviate these concerns. Market surveys indicate that consumers respond positively to packaging innovations when they understand that the preservatives are plant-based, safe, and intended to reduce food waste.

Economically, active packaging systems are currently more expensive to produce than conventional packaging, primarily due to the higher cost of natural actives and the additional processing steps required for incorporation and encapsulation. However, these costs may be offset by the reduction in product losses from spoilage, the premium pricing of organic goods, and the marketing advantage of offering longer shelf life without compromising clean-label claims. Large-scale adoption could also drive down costs as supply chains for bio-based packaging materials and natural actives become more developed.

Looking ahead, the integration of smart packaging technologies with natural preservative release could revolutionize the organic food industry. Imagine packaging that contains sensors to detect microbial activity and releases more preservative only when spoilage is imminent. Alternatively, time-controlled release systems could be developed using biodegradable polymers with specific degradation rates, ensuring optimal preservation during transportation and storage.

Advances in nanotechnology could allow for more precise control of active agent distribution and release kinetics, further enhancing performance. As sustainability, food waste reduction, and clean-label trends continue to shape consumer behavior, active packaging with natural preservative release is poised to become a standard feature in high-value organic food products.

Seaweed and Marine-Derived Preservatives

Seaweed and other marine-derived ingredients have emerged as one of the most promising frontiers in the search for natural, clean-label preservatives for organic food systems, combining functional efficacy with sustainability and consumer appeal. The use of marine bioresources in preservation is not entirely new coastal communities have historically used seaweed for food wrapping, moisture retention, and mild preservation but recent advances in marine biotechnology, extraction techniques, and food science have greatly expanded our understanding of the antimicrobial and antioxidant potential of seaweed-derived polysaccharides, peptides, and secondary metabolites.

These compounds, which include alginates, carrageenans, agar, laminarin, fucoidan, and marine-derived bioactive peptides, are being investigated not only for their preservative capabilities but also for their compatibility with organic certification standards and their ability to fit into the broader sustainability narrative that increasingly influences consumer purchasing decisions.

The antimicrobial action of seaweed-derived compounds is multifaceted and often synergistic. Sulfated polysaccharides such as fucoidan from brown algae and carrageenan from red algae possess inherent biological activity that can disrupt bacterial adhesion, inhibit biofilm formation, and interfere with viral and fungal replication. Some of these polysaccharides act by binding to microbial cell surfaces, altering membrane permeability, and ultimately causing cell lysis.

Fucoidan, in particular, has demonstrated broad-spectrum antimicrobial activity against Listeria monocytogenes, Escherichia coli, and Staphylococcus aureus—microorganisms of concern in fresh and minimally processed organic foods. Meanwhile, laminarin, another brown algal β-glucan, has shown immunomodulatory effects that may help enhance the natural defense systems of host cells, indirectly contributing to preservation in fresh produce and seafood.

Beyond polysaccharides, seaweed is also an abundant source of bioactive peptides with strong antimicrobial properties. These peptides can be generated naturally during the enzymatic hydrolysis of seaweed proteins or through targeted fermentation with lactic acid bacteria. They often act by penetrating microbial cell membranes and cr