From Photons to Peptides: Innovations in Food Preservation

Traditional food preservation methods such as heat pasteurisation, refrigeration and chemical additives have long ensured food safety. However, these methods come with trade-offs such as compromised nutritional quality, texture degradation, and consumer scepticism. Heat can degrade nutrients and alter food structure and chemical preservatives raise health concerns. Refrigeration slows microbial growth but does not eliminate pathogens. Science is advancing a new generation of precise, non-thermal preservation technologies. Innovations such as antimicrobial photodynamic therapy, adaptations of ionising radiation-based approaches, and natural antimicrobial peptides provide more targeted and effective solutions. These emerging tools are helping to overcome the limitations of conventional methods, making food safer, longer lasting, and more aligned with modern consumer and sustainability demands.

Antimicrobial Photodynamic Therapy (aPDT): Breaking the Thermal Barrier

Although light-based methods are increasingly preferred over heat-based techniques, traditional versions of such methods, such as UV treatment, often lack precision and can damage food quality, especially when inappropriately used. However, a more innovative method, aPDT, originally used in clinical medicine, makes progress by combining food-grade photosensitisers (e.g. curcumin or riboflavin) with specific light wavelengths to generate targeted antimicrobial reactions.

While broad-spectrum UV can indiscriminately affect food components, aPDT’s reactive oxygen species specifically attack microbial cells but leaves nutrients intact.  Chen et al recently showed that curcumin-based aPDT extended salmon shelf life by inactivating several groups of spoilage bacteria while maintaining texture and colour. Similar applications in dairy products also showed significant reduction of spoilage bacteria without impacting nutrient composition.

Nevertheless, further optimisation of the technology is needed to fully exploit their potential. For example, depth of light penetration can limit uniform treatment, and some photosensitisers may also alter food appearance. Advancements in photodynamic inactivation such as Light-Emitting Diodes (LED) array technology and development of colourless, food-grade photosensitisers are already solving these problems.

Ionising Radiation: The Deep-Penetration Solutions

Where surface treatments prove inadequate, short wavelength high intensity ionising radiation, such as gamma rays or x-rays, provides a more comprehensive solution by penetrating food products and disrupting microbial DNA without generating the heat that can compromise food quality. Ionising radiation has been used in food preservation for several decades. However, its large-scale adoption, particularly for meat and dairy products, has been limited by certain drawbacks. In addition to being energy intensive, ionising radiation interacts with water molecules to produce free radicals, which can accelerate lipid oxidation and degrade the sensory qualities of food. Combining irradiation with modified-atmosphere packaging (MAP) technology to create non-oxidative environments now helps manage this challenge for certain food types.

Despite International Atomic Energy Agency, and WHO endorsements, public perception remains a hurdle. Promoting broader adoption will require transparent communication about the safety and benefits of the technology, potentially supported by rebranding it as “cold pasteurisation”.

Antimicrobial Peptides: Nature’s Nano-weapons

Use of naturally-derived antimicrobial peptides (AMPs) in food preservation is gaining traction in response to growing consumer demand for clean-label, and chemical-free foods. These molecules, isolated from diverse sources including plants, insects, and marine organisms, provide targeted antimicrobial action with limited toxicity concerns compared to synthetic preservatives.

Nisin is the most widely used AMP in food preservation and has  demonstrated efficacy against certain food spoilage microorganisms such as Listeria monocytogenes. However,  newer discoveries, such as peptides from garlic or marine sources, show broader spectra of activity, effective against a wide variety of bacteria, viruses, parasites, protozoa, and fungi.

Nevertheless, stability of these delicate AMPs in food matrices will be critical for their widespread commercial application. Researchers are addressing these challenges  through innovative delivery systems such as encapsulation in edible films or nanoparticles.

Future Perspectives:  Integrated, Smart Preservation Systems

Next-generation food preservation systems will combine advanced technologies into smart, adaptive systems. These integrated solutions will enhance food safety while preserving quality and nutrition.  Public enlightenment through transparent communication about the safety and benefits of technologies will drive public acceptance and commercialisation. Nanotechnology will enhance natural preservative delivery and efficacy. Ultimately, this shift in preservation methods will reduce food spoilage, and food waste, helping to safeguard global food supply from farm to fork.

How We Can Help

At Braintree Innovation & Research Advisory, we stay at the forefront of emerging technologies in the agri-food sector, including food safety and preservation. Through our technology advisory services, we assist innovators in identifying and evaluating cutting-edge technologies, ensuring  alignment with product and market demands. Our technical and regulatory due diligence services also guide investors in making informed, innovation-driven investment decisions in science-led food innovations.