To meet the burgeoning demand for shelf-stable beverages, manufacturers are employing several methods for controlling microbial growth in beverage systems stored at ambient temperatures. Canned and bottled beverages are typically pasteurized or filled under aseptic conditions, eliminating the need for preservative systems. However, it is difficult to consistently maintain 100% aseptic operating conditions, and “hot packing” is not an option for beverages in non-rigid containers. One alternative is a preservative system of potassium sorbates and/or sodium benzoate to control the microbial growth of yeasts and mold in non-rigid containers to allow for extended shelflife stability.
Scientific research strongly supports that the antimicrobial efficacies of these preservatives can be greatly enhanced with the addition of polyphosphates. Sodium hexametaphosphate has demonstrated the ability to behave synergistically with preservative systems to allow reduction of potassium sorbate and sodium benzoate usage, while maintaining the required shelflife extension. It has been demonstrated that the chelating capability of polyphosphates can enhance antimicrobial efficacy by chelating the essential metals necessary to support microbial cell walls, which in turn causes loss of cell viability.