Is Fermentation the Safe Gateway for Steviol Glycosides as Food Additives?

In a recent scientific opinion published by the European Food Safety Authority (EFSA) on December 20, 2023, the EFSA Panel on Food Additive and Flavourings (FAF Panel) evaluated the safety of a new process to produce steviol glycosides using a genetically modified strain of Yarrowia lipolytica called Y. lipolytica VRM. The findings indicate that steviol glycosides produced through fermentation of simple sugars by this yeast strain do not pose any safety concerns as a food additive, when used as recommended.

The manufacturing process of steviol glycosides by Y. lipolytica VRM may result in impurities that differ from those found in other steviol glycosides. As a result, the FAF Panel concluded that separate specifications are needed for the food additive produced through this specific process. However, it was determined that viable cells and DNA from the production strain are not present in the final product.

To address concerns of potential genotoxicity, the absence of kaurenoic acid in the proposed food additive was demonstrated using a detection method with a limit of 0.3 mg/kg. The FAF Panel deemed this analysis sufficient to dismiss genotoxicity concerns. Considering that all steviol glycosides follow the same metabolic pathways, the Panel concluded that the new steviol glycosides would fall within the same group of substances.

Based on existing data on rebaudioside M and structurally related steviol glycosides, the FAF Panel determined that a similar metabolic fate and toxicity can be expected for the food additive produced through fermentation. Results from bacterial reverse mutation and in vitro micronucleus assays indicated the absence of genotoxicity from the food additive.

The established acceptable daily intake (ADI) of 4 mg/kg body weight (bw) per day, expressed as steviol equivalents, was deemed applicable to the proposed food additive. Consequently, the FAF Panel concluded that there are no safety concerns for steviol glycosides, particularly Rebaudioside M, produced through fermentation using Y. lipolytica VRM, when used as a food additive according to the proposed uses and use levels.

In light of these findings, the question arises: Is fermentation the safe gateway for incorporating steviol glycosides as food additives? The EFSA's scientific opinion suggests that the use of Y. lipolytica VRM in the fermentation process for producing steviol glycosides does not raise any safety concerns. This opens up possibilities for utilizing this innovative approach to meet the demand for steviol glycosides as food additives in a safe and controlled manner.