Packaging: Aseptic Filling

Abstract

Aseptic packaging is a well-accepted technique for the preservation of liquid and particulate foods. Sterilization of food packaging materials and food contact surfaces is indispensable in the aseptic packaging system. The common methods of sterilization include chemical methods, thermal methods, and radiation methods. Hydrogen peroxide sterilization followed by hot air is the most common method used in aseptic packaging. Sterilization of packaging materials using hydrogen peroxide followed by ultraviolet (UV) irradiation and heat also has been accepted for industrial application, and its application is expected to grow for aseptic processing and packaging. Dry heat sterilization is not suitable for heat-sensitive packaging materials like many plastic items. Hot air is used as a sterilizing agent for paper-based packaging materials, while saturated steam is a preferred treatment method for sterilizing metal food contact surfaces. The combination of peracetic acid with hydrogen peroxide and heat also deserves attention to the sterilization of food contact surfaces in aseptic packaging. Light pulse technique appears to be an effective nonthermal method of sterilization of packaging materials and equipment surfaces in aseptic packaging systems and is being used in many commercial aseptic systems. Ionizing radiation is not commercially implemented in-line with aseptic packaging systems due to its high cost and nonuniform dose delivery to preformed containers. Presently, industries are trying to move away from chemical methods to new nonthermal methods such as light pulse, UV laser light, γ-rays, electron beams, and plasma discharge for the sterilization of packaging materials. The design of cost-effective machines and sterilization processes of these methods are the most important tasks to be accomplished before in-line sterilization of food packaging materials and food contact surfaces.