Recent advances in the application of pulsed light processing for improving food safety and increasing shelf life

Abstract

Background: New technologies of non-thermal disinfection such as pulsed light (PL) have emerged lately as an alternative to traditional (thermal and chemical) disinfection and preservation methods. PL can be used to decontaminate a wide variety of foods as well as to decontaminate contact surfaces, thus improving safety in foods and extending their shelf life. Moreover, this technology can prevent or reduce some of the detrimental effects of traditional methods on nutrients and bioactive compounds of food products. Scope and approach: The combination of PL with other techniques such as ultraviolet light (UV), thermosonication (TS), pulsed electric fields (PEF), manothermosonication (MTS), etc., can improve the effectiveness of the decontamination process. Therefore, in this review, some of the most relevant studies evaluating the potential application of PL treatments to decontaminate food samples, and its impact of nutritional and physicochemical quality parameters will be discussed. Key findings and conclusions: PL treatments are suitable for microbial decontamination in transparent drinks and for surface contaminated foods without complex microstructures. They also can be used for meat, fish and their by-products However, it is still necessary to evaluate the appropriate treatment conditions (number of light flashed, voltage, distance between sample and flash light, spectral range of light flashes and contamination) for each food and microorganism separately to improve the effectiveness and minimize the appearance of negative attributes reducing the quality of product as, in some cases, PL can have a negative impact on the photosensitive compounds and sensory properties of food products.

Biofilms Formed by Pathogens in Food and Food Processing Environments

“…PL is a technology that can be used to decontaminate surfaces by generating short-time high-energy light pulses (millions or thousands of a second) of an intense broad spectrum (200-1100 nm). PL can be used to decontaminate a great variety of foods as well as to decontaminate contact surfaces, thus improving safety in foods and extending their shelf life [137]. The antimicrobial effect is based on strand breaks that lead to the destruction/chemical modification of the DNA and thus prevent the replication of the bacterial cell [138].…”

“…A comprehensive review in the literature underlined the various researches directed mainly at inactivation of pathogens in food or on surfaces and for preventing biofilm formation [137]. While there are often considerable differences in the rate of microbial inactivation by PL, a maximum reduction of 3-log was typically achieved, which is below the reduction performance standard of 5-log required by HACCP regulation [138].…”

Edible Coating and Pulsed Light to Increase the Shelf Life of Food Products

“…Fundamentals PL, also known as pulsed UV light, high-intensity broad-spectrum pulsed light, pulsed white light, or intense light pulses, is a nonthermal technology that has gained increasing interest in the last decade, from both the research world and food processing industry, as an alternative to traditional chemical and thermal microbial decontamination methods of foods, food contact surfaces, and equipment [204,205].…”

“…The limitations to the use of PL technology in the decontamination of solid matrices are common to other methods applied in the food industry to decontaminate raw fruits and vegetables or packaging material, such as washing with solutions containing chlorine, peracetic acid, or hydrogen peroxide [205,209]. The challenge is, therefore, represented by engineering solutions as the re-design of the equipment to promote more uniform surface irradiation of rough surfaces of solid and opaque liquid products [13,204].…”

Packaging aspects for processing and quality of foods treated by pulsed light

“…Therefore, there must be efforts on the part of researchers aiming at understanding the real packaging requisites to package food processed by these technologies. Once these issues F I G U R E 1 Schematic diagram of nonthermal treatment of foods with pulsed light (Mahendran et al, 2019). Figure used with permission from Elsevier, Copyright 2019are clarified, together with issues inherent in foods, the successful commercialization of the technology will become prevalent (Guillard et al, 2010;Heinrich et al, 2015;Marangoni Júnior, Cristianini, et al, 2019).…”