ABSTRACT
434This chapter describes the use of modified atmosphere (MA) as it relates to the storage, transportation, and packaging of fresh fruits and vegetables. Modifying the atmosphere surrounding fresh produce can have several beneficial attributes, including reduction in the produce respiration rate, delayed ripening, and enhanced inhibition of microbial growth. Physiological responses to modified atmospheres are reviewed along with the effects on microbial growth and produce decay. Four types of modified atmosphere packaging are covered: the common methods of using semi-impermeable films, perforations, and vacuum packaging, along with the use of diffusion tubes, which is primarily at the research stage. Differences between modified atmosphere storage and controlled atmosphere storage are covered along with an overview of the approaches that have been researched for modified atmosphere storage. The challenges to implement and maintain modified atmosphere during transportation are presented along with some approaches to overcome these challenges.
Owing to the nature of the packaging materials and methods used in modified atmosphere applications, quality control and quality assurances can be a challenge. This chapter presents the common off-line and in-line methods used for quality control and quality assurance and some of the instruments used for measurements, including headspace analyzers and leak package testers. An overview of regulatory 435compliance is given with regard to food safety when using modified atmosphere technologies.
The chapter ends with a discussion of recent advances in modified atmosphere technologies, much of which is still in the research stage. These advances include active packaging, environmentally conscious designs, use of essential oils, superatmospheric applications, nondestructive quality assurance measurements, and the use of computer software in the design of modified atmosphere packages.
