Modern packaging systems to prolong shelf life
Active Packaging Applied to Dairy Products
Ozlem Kizilirmak Esmer and Busra Sahin
Ege University, Engineering Faculty, Food Engineering Department, Bornova Izmir, Turkey
A great technological development in food packaging has occurred over the past few decades to maintain food safety and quality by satisfying consumer demands related to the use of more natural forms of preservation methods. And active packaging technology is definitely one of the most important innovations in food packaging and can be defined as a packaging technique that changes the condition of the packed food (EU, 2011) to extend shelf life or to improve safety or sensory properties, while maintaining the quality of the packaged food (Ahvenainen, 2003). Active packages are designed to perform a role other than to provide an inert barrier between the product and the outside environment, using the possible interactions between food and package in a positive way to improve product quality and acceptability (Singh et al., 2011).
Sometimes active packaging can be confused with another innovative packaging concept—intelligent packaging. But intelligent packaging monitors the condition of packaged food or the environment surrounding the food during transport and storage by the components integrated in or on to the package. Intelligent packaging provides the user with reliable and correct information on the conditions of the food, the environment and/or the packaging integrity (EU, 2011). But intelligent packaging concept and active packaging concept are not mutually exclusive. Both packaging systems can work synergistically to realize so-called smart packaging. Smart packaging provides a total packaging solution that on the one hand monitors changes in the product or the environment (intelligent) and on the other hand acts upon these changes (active) (Vanderroost et al., 2014).
Active packaging techniques can be divided into two categories for preservation and improving quality and safety of foods: 
compounds to the packaged food or into the head-space of the package, such as carbon dioxide, ethanol, antioxidants, and preservatives.
In active packaging, active compounds can be incorporated into the packaging material or integrated to the closure of the bottle, or can be directly added to the package in the form of sachets or labels.
Since the main objective of the active packaging is to extend shelf life and to enhance safety of food, it is especially useful for fresh foods and extended shelf life foods. Dairy products are one of the main food products that have found application area for active packaging technology since dairy products are very susceptible to microbiological spoilage, enzymatic and nonenzymatic spoilage because of the characteristics and processing conditions of the dairy products.
-  Absorbing systems (scavengers) • Releasing systems (releasers) Absorbing systems remove undesired compounds such as oxygen, carbon dioxide,ethylene, excessive water, taints, some unwanted aromatic compounds and other specific compounds from the package, whereas releasing systems actively add or emit Advances in Dairy Products, First Edition. Edited by Francesco Conto, Matteo A. Del Nobile, Michele Faccia, Angelo V. Zambrini, and Amalia Conte. © 2018 John Wiley & Sons Ltd. Published 2018 by John Wiley & Sons Ltd.