**1. Introduction**

Food preservation involves the art and science of extending food quality/integrity or maintaining its nature for a specified period of time [1]. The food preservation techniques includes the use of packaging enclosure to protect food from external factors which may interfere with initial nature or quality of the food. As a food preservation element, food packaging provide enclosure to food and supports the food product against external invasion. It provide an integral role of *containment, protection communication and preservation* of the inherent quality of the package food [2]. Food packaging provide several advantage in food production that includes; nutrient stability/preservation, information containment and communication including information on ingredients (type and quantity), shelf life and also quality/integrity protection. Therefore, the role of food packaging in food reservation cannot be overemphasized. Food packaging are usually in direct contact with the food, therefore there is direct association which can result to some changes. Some of these changes may render the food unsafe for consumption or may speed up chemical process which may poses organoleptic loss. The advent of food-packaging interaction depends on the nature and quality of the

packaging material. Some packaging provide 100% barrier to any external factors why some may allow lite interaction with external system as such can easily pose the food to contamination and or other reactive changes, therefore a packaging selection is critical to the shelf stability of the food and needed to follow stringent process.

An important requirement in selecting packaging systems for foods is the barrier property of the packaging material. To keep a food product crisp and fresh, the package must provide a barrier to moisture. Food changes such as off-flavor and rancidity may occur if the packaging material has a poor barrier to oxygen, allow gas permeation and by allowing passage of light to the food. Original organoleptic properties of a food can be maintained by using a packaging material that offers a good barrier to moisture, gasses and aroma. Thus, properly selected packaging materials are beneficial in extending the shelf-life of foods. A food's characteristic flavor and aroma are the result of a complex construct of hundreds of individual constituent compounds interacting to produce a recognizable taste and aroma. Therefore, if one or more flavor constituents are altered or diminished, food quality may be reduced. A reduction in food quality may result from the interaction of the food component with external environment or with the internal packaging environment which hinders the ability of the packaging role. The way food package influences the integrity of the packaged food, food under packaging also affect the packaging integrity when it react or possess chemical changes to the packaging films therefore effective packaging system is the one which passes no effect to the food or to the packaging or vice-versa. Plastic and metal packaging usually react if used in direct contact with acidic/corrosive foods therefore needed to be incorporated together with second barer, transparent plastic and glass jars are not advisable to light reacting foods because light can react with food components (such as vitamin and lipid) and speed deteriorative chemical process such as oxidative rancidity. As interaction principle, permeation of volatile aromatic compound into or out of a packaging system causes unbalanced change in flavor profile which changes the sensory properties of the packaged food. Therefore effective packaging that can extend shelf life of a flavored food should provide a total barrier to volatile aromatic compound permeation. Packaging such as aluminum foil are used which provide inert barrier than other polymers/plastic [3]. Plastic packaging such as low-density polyethylene (LDPE), polypropylene (PP), polycarbonate (PC) and polyethylene terephthalate (PET) provide permeation flavor and oxygen as such cannot be used on highly flavored compound or products that are sensitive to oxygen such as fat and oils. The characteristic permeation of oxygen and flavor in LDPE and PP increase linearly while flavor permeation increase with increase in oxygen permeation in PC with increase in flavor absorption in PET with increase in storage duration [4]. Migration on the other hand, causes sensory changes at smaller rate and affect consumer health at a higher rate of occurrence. The effect of migration as interaction may be seen on food as color change, taints and off-flavors [5]. This chapter explored the interaction principles in a food packaging system as well as the preservation effect of the interaction and ways to estimate/ascertain the extent of the interaction, the chapter covers the interaction methods, the effects and included the methodical approach to ascertain the effect of food-packaging interaction.

#### **1.1 Food-packaging interaction**

When food products are packaged, the food is in direct contact with the inside surface of the packaging. It is possible for interaction between the food and the
