Pulsed light as a novel decontamination technology: factors affecting microbial inactivation
Special Symposium - Innovations in Food Technology (LMC Congress)
Hygiene, Hygienic Design & Unit Operations (Food-5b)
Keywords: pulsed light, non-thermal process, decontamination, microbial inactivation, minimally processed food
Pulsed light as a novel decontamination technology: factors affecting microbial inactivation
A. Lasagabaster and I. Martínez de Marañón*
AZTI-Tecnalia, Food Research Division, 48012 Sukarrieta (Bizkaia), Spain
*Corresponding author. imaranon@suk.azti.es
Tel.: +34 94 602 94 00; Fax: +34 94 687 00 06
Consumers have a growing preference for fresh-like, minimally processed and convenience food products, as well as for safe and high quality foodstuffs. The need to assure the microbiological safety of food products without compromising their sensory and nutritional quality has led to development of suitable non-thermal preservation technologies, such as pulsed light. Pulsed light is a novel process which consists of high power pulses of a broadband light emission with a considerable amount of light in the short-wave UV spectrum. The aim of this work was to study the impact of some pulsed light processing factors on microbial inactivation effectiveness by pulsed light and to establish the most effective conditions to inactivate Listeria innocua, a non-pathogenic surrogate for Listeria monocytogenes.
A single light pulse induced more than 7 Log CFU reduction at relatively low doses (0.7 J.cm-2) and short treatment time (325 µs) whereas no significant rise in temperature was observed. Microbial inactivation by pulsed light increased with the pulse energy and the number of pulses. Furthermore, the shorter the distance of the sample from the lamp the better the efficacy of the process. Finally, L. innocua reduction in both liquid and solid samples increased with the light dose received by the sample, i.e. the higher the microbial exposure to the light the better the efficacy of the pulsed light process. Although additional studies are needed to point out the suitability of this process to improve the safety of fresh or minimally processed food products, pulsed light appears as an economical and promising non-thermal decontamination technology for this kind of products.
Presented Thursday 20, 10:15 to 10:20, in session Hygiene, Hygienic Design & Unit Operations (Food-5b).
