Influence of new packaging technologies on the growth of microorganisms in produce

Abstract

Several new technologies which are intended to extend the shelf life of respiring fruits and vegetables have been or are being developed. This is in response to the increased consumption of fresh fruits and vegetables and the desire to distribute branded products. The most widely studied and adopted technologies are controlled or modified atmosphere packaging. These packaging methods alter the gases surrounding a respiring product in order to slow the normal senescence or decay of the product. Controlled or modified atmosphere packaging can also affect the types and growth rates of microorganisms associated with produce. This may slow the rate of deterioration of the produce but could also provide sufficient time for human pathogens to develop rendering the product unsafe while still edible. This possibility has not been thoroughly researched and so interest in the safety of these technologies exists. Of primary importance is the relationship between the growth rate of pathogenic microorganisms and the rate of decay of the produce. Produce which has spoiled beyond the point where it is edible is of much less risk than produce which remains edible while becoming infectious or toxic. The relationship between the formation of botulinum toxin and "edibility" of extended shelf-life packaged tomatoes is an example of such concern. Often measures of toxin formation are available but not directly compared to the likelihood that a product is acceptable and would be eaten. This paper discusses one such approach.