System design 5 "There are various factors to be considered in designing antimicrobial systems. Antimicrobial systems can be constructed by using antimicrobial packaging materi- als, antimicrobial inserts (such as Sachets) to generate antimicrobial atmosphere c ditions inside packages, or antimicrobial-edible food. ingredients in the formulation of foods Since antimicrobial packaging systems are designed to control the e growth of micro-organisms in packaged foods, the systems essentially consistofpackaging mate- nals (or packages), foods, the in-package atmosphere, target micro-organims,. and antimicrobial agents. These five elements are related to one another and to the find System design tuatures. To study the effectiveness ofantimicrobial food packaging systems with respect to the relative effects of these elements, many choices of combinations should be exam- ined using real food. systems-The majority ofresearchh's sbeen conducted usingculture media, which provides the richest nutritional quality and the most favorable environment for microbial growth, and antimicrobial packaging materials. Most micro-organisms in culture media are not stressed compared to micro-organisms under normal condi-. tions in foods. Many antimicrobial systems that have shown strong antimicrobial activity against target micro-organisms in culture media do not demonstrate the Same antimi- crobial activity when they are actually in the food systems-This is very common, and clearly shows the interactive effects. of food ingredients, micro-organisms, and antim- crobial agents. All of these factors have complex a single chemical mechanism-Therefore, its strongly recommended that experiments regarding the efficiency examination of an antimicrobial packaging system should be conducted using a real food instead of. culture broth or agar media.-Table 6.2 lists examples of antimicrobial food packaging systems which have been tried, mostlyby university researchers, over the past two decades.