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.

Avoiding Benzene Formation

Recognizing the potential of preservative enhancement with polyphosphates, ICL Performance Products LP introduced Benephos™ to the beverage industry in 2006. The application is a mixed cation (potassium and sodium) polyphosphate that assists beverage manufacturers in extending product shelflife, while reducing the sodium contribution. Microbial challenge studies also have demonstrated the effectiveness of Benephos in juice-based beverage systems.

Benephos also is being utilized in beverages that have been reformulated as a result of the 2007 FDA announcement regarding the findings of elevated benzene levels in specific beverages that contained the combination of ascorbic acid and sodium or potassium benzoate. Several manufacturers have looked at alternate means to reducing the potential for benzene formation in products that require ascorbic acid—in addition to a good preservative to extend shelflife. Benephos is thought to tie up transition metals, such as copper and/or iron, which may act as catalysts for the benzene formation, thus reducing potential for formation.

Reducing Sodium Levels

Formulators that used sodium polyphosphates in the past also are tapping into the potential of Benephos as a method for reducing sodium concentrations in their products. As a mixed cation hexametaphosphate, the molar replacement of potassium to sodium on this medium-chain-length polyphosphate is, on average, 70%. The potassium ranges between 23-26%, while the sodium is 5-8%. Additionally, Benephos is just as soluble as sodium hexametaphosphate and can be used as a 1:1 replacement for straight sodium hexametaphosphate.

According to Nadeen Myers, MTS, food phosphates specialist for ICL Performance Products LP, “Benephos is invaluable to beverage and dairy manufacturers for increasing their products’ shelflives. For example, cold-filled beverages with a low level of fruit juice can reduce the potassium sorbate and/or sodium benzoate levels by 50% (from 1,000-500ppm), with the addition of 0.1-0.5% (1,000-5,000ppm) Benephos. This change in formulation results in reduced ingredient costs and improved flavor profile.”

For more information:

ICL Performance Products LP, St. Louis, Mo.
Nadeen Myers, 800-244-6169