Recent studies have highlighted treatments with high-energy ionizing radiation, which is able to inactivate degradative enzymes present in the food, delaying its deterioration, and to inhibit the multiplication of microorganisms or to prevent the germination of potatoes, garlic, and onions. The use of this method is rather limited in Europe (Directive 1999/2/CE, Directive 1999/3/CE), though it is authorized in many member states, while its use proves to be wider in countries outside the European Union. Irradiation is also authorized in the United States (§179.25; §179.26) for the following:
- • HPP: High-pressure processing
- • APP: Cold atmospheric pressure plasma
- • PEF: Pulsed electric field
- • Pulsed light for the treatment of food: allowed in the United States for microorganism control §179.41
- • Pasteurization of dry food
- • Power ultrasound
- • Radiofrequency radiation for the heating of food, including microwave frequencies (§179.30)
- • Ultraviolet radiation for the processing and treatment of food (§179.39)
- • Carbon dioxide laser for etching food (§179.43)
The problems associated with nonthermal methods include spore injury instead of death and the rise in product temperature associated with the processing method (Morris et al., 2007). The safety and microbiological quality of food processed using these technologies needs to be further explored.
Weiss et al. (2009) affirmed the use of nanoemulsions for the delivery of antimicrobials. Due to small droplet size (high ratio area to volume), antimicrobials such as lysozyme, nisin, and lauric alginate would have a better activity.