The U.S. Pharmacopeial (USP) Convention has released new reference standards for the sweeteners rebaudioside A and stevioside, which are derived from the leaves of the Stevia plant. The new reference standards complement the written testing standard for high-purity rebaudioside A in the Food Chemicals Codex (FCC), a collection of documentary standards for food ingredients to be released in late August.

The reference standards for rebaudioside A and stevioside are authenticated pure chemicals. Producers and purchasers can compare their ingredients with those in the reference standards to verify quality, purity, strength, and consistency.

“With the advent of Stevia-based sweeteners on the U.S. food market, USP aimed to give the tools needed for the buyer of such a sweetener or for the ethical seller to prove with high reliability the purity and quality of a particular batch,” Markus Lipp, PhD, director of food standards for USP, told Food Quality. “This USP monograph, in conjunction with the USP reference material, offers for the first time the full package of an appropriate testing method plus an authenticated reference standard that is needed to establish, document, and maintain a quality analytical testing procedure for this new ingredient.”

The authenticated reference standard will allow purchasers to make more informed choices, said James Griffiths, PhD, vice president of food, dietary supplement, and excipient standards for USP. “Given the uncertainty surrounding many globally-sourced food ingredients and the persuasive nature of the ingredient marketing contacts, it can be daunting for a discriminate buyer to know if what is being offered is the ‘real deal,’” he told Food Quality. “And in the face of multiple ingredient manufacturers all dropping off supposedly true samples for the end user to purchase, it can be confusing to select which is the one that will go into a flagship brand. Use of an authenticated reference standard will allow the purchaser to make an informed choice regarding the identity and purity of the next ‘new thing.’”

Everyday Resource
These standards can be an everyday resource for manufacturers and users. “FCC monographs set criteria and analytical methods to authenticate and to determine the purity and quality of food ingredients,” Dr. Lipp said. “FCC is a resource that aids in making the food supply chain safer and allows manufacturers and users to distinguish genuine products from inferior and/or adulterated products.”

Dr. Griffiths added, “Every day, or at least with every new lot or new supplier to be qualified, the authenticated reference material serves its role as discriminator of the ingredient that is wanted and purchased, and obviates, or at least lessens, the chances of adulterated or contaminated materials being inadvertently used.”

The USP’s Reference Standards Expert Committee, a group of independent volunteer experts, has thoroughly tested and endorsed the new reference standards. “USP will publish a new edition of the Food Chemical Codex every two years and additional published supplements to the FCC in the interim,” Dr. Lipp said.