New technologies are increasingly emerging as alternatives to 10 conventional treatments. This review summarizes recent advances in packaging solutions that enable in-package applications of pulsed light, UV-C radiation, high-pressure processing (HPP), ohmic heating, ultrasound, microwave-assisted thermal sterilization (MATS) and microwave-assisted pasteurization (MAPS). Emphasis is given to polymer packaging materials, as these are the main structures currently employed in such applications. The prerequisites for each operation are mapped, such as high transmittance and optical homogeneity for pulsed light and UV-C radiation, isostatic compressibility, robust sealing, and dimensional recovery for HPP, electro-thermal stability and field uniformity for ohmic heating, and mechanical resilience to cavitation in ultrasound. Material choices and their characteristics are detailed, including thickness, crystallinity, additives, coatings, and properties related to barrier, mechanical, and optical performance. Adjustments involving barrier properties, sealing force, and transparency are discussed, along with polymer-dependent effects on overall or specific migration. A validation process flow and headspace guidelines are outlined to prevent shadowing, particularly for pulsed light and UV-C radiation, and defects in HPP. Studies also indicate that optimized processing can extend shelf life for products such as meats, dairy, fruits and vegetables, and fish. The conclusion highlights that enabling materials and customized process parameters make emerging routes scalable while maintaining food safety, quality, and sustainability.
Lima et al. (Mon,) studied this question.