Scientific Alert Note

Pulsed light technology, a promising new process for enhancing seafood quality

Pulsed light technology is a promising novel process for seafood products decontamination. This emerging non-thermal technology could be used as an alternative to traditional thermal and chemical treatments to improve safety and increase shelf life of lightly preserved fish products like cold smoked fish. The suitability of this method on seafood is evaluated within the SEAFOODplus project HURDLETECH.

Authors: Iñigo Martínez de Marañón and Amaia Lasagabaster, AZTI-Tecnalia, Spain

In one of the SEAFOODplus projects, HURDLETECH, a study is being performed to find out if pulsed light technology would be suitable for use in order to improve the safety of seafood products, as well as prolonging their shelf life.

Pulsed light technology is a novel non-thermal process which consists of a successive repetition of high power pulses of broadband emission light. The emitted light spectrum includes wavelengths from 200 to 1000 nm with a considerable amount of light in the short-wave UV spectrum. For the emission of a single light pulse, the electric power is stored in an energy storage capacitor and later released quickly to a Xenon lamp. Then, this lamp emits short duration (325 µs) and high intensity light flashes which are transmitted to the surface of the products.

The US Food and Drug Administration approved the use of pulsed light technology “for production, processing and handling of foods” up to light doses of 12 J.cm-2. Within the HURDLETECH project of SEAFOODplus AZTI-Tecnalia is studying the suitability of this emerging non-thermal technology to improve the safety and increase the shelf life of seafood products.

When using pulsed light technology on seafood, the method has proven to be a quick, effective and non-thermal decontamination process. The treatment reduces levels of spoilage and pathogenic microorganisms isolated from seafood products. However, since the light does not penetrate the product deep enough, the treatment is limited to only reduce microbial contamination of the surface of solid seafood products. It also decontaminate certain liquids, food processing devices applied in the seafood processing chain or even packaging materials.

Even if additional information is needed, pulsed light technology appears to be an efficient decontamination process which could be applied to improve the microbial safety (Listeria hazard) and prolong the shelf life of seafood products, in particular minimally processed and/or convenience fishery products. Due to the fact that the time required to inactivate microorganisms is very short, this technology could successfully be implemented in high speed processing lines for the food industry.