Harmonisation of Terms

The International Stevia Council has developed a list of terms on all things related to stevia.

Regulatory

ADI 

ADI stands for Acceptable Daily Intake and describes an estimate of the amount of a food additive that can be consumed daily over a lifetime without risks to health. It is usually expressed as milligrams of the substance per kilogram of body weight per day.  

The ADI for steviol equivalents is 4 mg per kg of body weight per day (4 mg/kg bw/day).   

Dietary Supplements 

According to the US Food and Drug Administration’s definition, these are: “Products that intended to supplement the diet. These products are typically botanicals, vitamins, minerals, amino acids and extracts.” 

Applicable countries: 

  • United States – labeled with “Supplement Facts” and are regulated differently from conventional food 
  • Example: Stevia leaves and extracts have been permitted for use in dietary supplements in the US since 1995 

A reference can be found here.  

EFSA 

EFSA is an acronym for the European Food Safety Authority and is the agency of the European Union that provides independent scientific advice and communicates on existing and emerging risks associated with the food and feed chain. EFSA was established in February 2002 and is based in Parma, Italy.  

EFSA is tasked with science-based evaluation of safety and preparation of scientific opinions and advice to support legislation in the EU. This activity is sometimes called risk assessment. The advice of EFSA underpins food safety in the EU.  

Steviol glycosides extracted from plant leaves received a positive safety opinion by the EFSA’s Scientific Panel on additives (the ANS Panel) in April 2010. The European Commission requested EFSA to conduct a risk assessment following submission of three dossiers supporting requests for authorization for use in the EU as a sweetener. The favorable scientific opinion opened the door for the approval of steviol glycosides to be authorized as sweetener in food by the European Union which took place on 11 November 2011. 

The EU regulation on Steviol glycosides can be found here.  

EUR-Lex – 32011R1131 – EN – EUR-Lex (europa.eu) 

FCC Monograph 

FCC Monographs on Rebaudioside A and Steviol Glycosides 

In 2009, the FCC monograph for Rebaudioside A was established and published in the 2009 FCC 6, Second Supplement and updated in FCC 8, Second Supplement. 

In 2013, the FCC monograph for Steviol Glycosides was established and published in the FCC 8, Third Supplement in June 2013. In 2017, the FCC published updated analytical methods to identify additional glycosides found in the leaf. FCC is working to update this monograph based on the new Steviol Glycosides monograph from the 91st JECFA Session in Feb 2021 which will include updated analytical methods, broader number of steviol glycosides, and new production technologies. 

These monographs contain specifications related to the ingredient’s identity, purity, and potential impurities, as well as supporting analytical test procedures utilizing USP Chemical Reference Standards used to confirm quality of food ingredients. 

The Chemical Reference Standards were established through USP’s open, independent, and collaborative testing process to ensure their suitability for the intended uses in the monograph test procedures. The FCC Rebaudioside A and Steviol Glycosides monographs and associated Reference Standards provide an objectively established standard against which both producers and purchasers can compare their ingredients to ensure their quality. 

Food Chemicals Codex (FCC) 

The FCC is a compendium of internationally recognized standards for the purity and identity of food ingredients. It features about 1,100 monographs, including food-grade chemicals, processing aids, foods (such as vegetable oils, fructose, whey, and amino acids), flavoring agents, vitamins, and functional food ingredients (such as lycopene, olestra, and short chain fructooligosaccharides). 

The FCC is published in the United States by the U.S. Pharmacopeia, but regulatory agencies, manufacturers, vendors, and other users of food ingredients recognize it worldwide. In some countries, FCC standards may serve as a legal requirement for manufacturing or importing a food ingredient. 

Published since 1966, the FCC plays a key role in safeguarding commerce and public health by providing essential criteria and analytical methods to authenticate and determine the quality of food ingredients. FCC standards are beneficial to all members of the food industry: 

(a). They are used as agreed standards between suppliers and manufacturers in ongoing purchasing and supply decisions and transactions and 

(b). They can aid manufacturers in distinguishing genuine products from inferior or adulterated ingredients and substances, thereby helping to make the food supply chain safer and assuring consumers of the quality of the food products they eat.  

GRAS 

GRAS is an acronym for Generally Recognized as Safe. This is a regulatory designation used in the United States where substances added to food must either be approved by the Food and Drug Administration (FDA) as food additives or through a self-affirmation process, be generally recognized as safe (GRAS). While there is no premarket notification required for GRAS substances, the standard for safety that applies to general recognition is the same as the standard that is applicable to food additives. 

The United States FDA offers a voluntary GRAS notification program. An inventory of GRAS notifications, along with corresponding agency responses, is available online. For more information about GRAS or the GRAS process, visit the link below. 

A reference can be found here

Steviol glycosides are GRAS for general purpose sweetener use. This regulatory status is the result of multiple GRAS notifications for Steviol glycosides that have been submitted to the FDA since 2008. To date, the FDA has responded to each of these notifications stating that the Agency has no questions or objection to safety findings at this time regarding the GRAS status of purified Steviol glycosides meeting purity criteria of not less than 95% total glycosides. 

Codex Alimentarius  

The Codex Alimentarius is a collection of standards, guidelines and codes of practice adopted by the Codex Alimentarius Commission (CAC) which is the central part of the Joint FAO/WHO Food Standards Programme. CODEX was established in 1963 by FAO and WHO to protect consumer health and promote fair practices in food trade. 

Codex standards ensure that food is safe and can be traded. The 188 Codex members have negotiated science-based recommendations in all areas related to food safety and quality. 

The Codex Committee on Food Additives (CCFA) establishes the standards for food additives, including the sweeteners and therefore steviol glycosides.  

CCFA mandate is:  

  1. to establish or endorse permitted maximum levels for individual food additives;
  2. to prepare priority lists of food additives for risk assessment by the Joint FAO/WHO Expert Committee on Food Additives (JECFA);
  3. to assign functional classes to individual food additives; 
  4. to recommend specifications of identity and purity for food additives for adoption by the Commission;
  5. to consider methods of analysis for the determination of additives in food.  

JECFA has prepared specification Monographs for Steviol Glycosides  

GSFA 

GSFA stands for the Codex General Standard for Food Additives. Any food additive needs to be included in the GSFA data base in order to be placed in the market at international level. 
   
The GSFA database can be found here: GSFA Online Food Additive Index 

Steviol Glycosides in GSFA can be found here: GSFA Online Food Additive Group Details for STEVIOL GLYCOSIDES 

INS No. 

INS (International Numbering System) is a number linked to Codex and refers to the number a food additive is assigned in the Codex classification system (CAC/GL 36-1989). 

INS for steviol glycosides is INS 960.   

Natural Health Products (NHP) 

Natural Health Products is a term used by the Health Canada to refer to probiotics, herbal remedies, vitamins and minerals, homeopathic medicines, traditional medicines (such as traditional Chinese medicines), and other products like amino acids and essential fatty acids.  

Applicable countries: Canada 

Example: Health Canada has published a safety monograph for Stevia. To date, Health Canada has approved the use of stevia and its extracts as a non-medicinal ingredient (sweetener) and stevia as a medicinal ingredient in multiple natural health products (NHPs). 

References can be found here.  

Novel food 

Definition: Novel foods are foods and food ingredients that have not been used for human consumption to a significant degree within the EU before 15 May 1997. A separate regulation is applied to GM-derived food and food ingredients. 

Applicable countries: European Union 

European Union: Stevia rebaudiana (plant and dried leaves) 

Applicant-Katholieke Universiteit Leuven Laboratory of Plant Physiology - 7 November 1997 

Commission Decision- refusing the placing on the market of Stevia rebaudiana – 2000/196/EC 

Regulation EC 258/97 of 27 January 1997 of the European Parliament and the Council lays out detailed rules for the authorization of novel foods and novel food ingredients

Commission Decision 2000/196/EC 22 February 2000 refusing the placing on the market of Stevia rebaudiana Bertoni

Clickhere for more information from Health Canada  

Click here for more information from Food Standards Australia/New Zealand - FSANZ 

MATERIAL CHARACTERIZATION 

Dulcoside A 

Dulcoside A is one of the associated glycosides found in the stevia plant.

  • Chemical formula of Dulcoside A 
    13-[2-O-6–deoxy-β-L-mannopyropyranosyl-β–D-glucopyranosyl]oxy] kaur-16-en-18-oic acid β-D-glucopyranosyl ester 
  • CAS number 
    64432-06-0 
  • Chemical formula 
    C38H60O17 
  • Molecular weight 
    788.87 

Rebaudioside A 

Rebaudioside A is one of the two major Steviol glycosides present in the Stevia leaf and is best known for its clean, sweet taste.Its sweetness intensity is around 200 times that of sugar, but will vary depending on the food or beverage in which it is used. Furthermore, it is very stable under a full spectrum of pH levels, heat and light, all conditions that are found in foods and food preparation. 

  • Chemical name of Rebaudioside A 
    13-[(2-O-β-D-glucopyranosyl-3-O-β-D-glucopyranosyl-β-D-glucopyranosyl)oxy]kaur-16-en-18-oic acid, β-D-glucopyranosyl ester 
  • CAS number 
    58543-16-1 
  • Chemical formula 
    C44H70O23 
  • Molecular weight 
    967.01 

Rebaudioside B 

Rebaudioside B is one of the associated glycosides found in the stevia plant. It is generally present in preparations of Steviol glycosides at levels lower than stevioside or Rebaudioside A. 

  • Chemical name is Rebaudioside B 
    (13-[(2-O-β-D-Glucopyranosyl-3-O-β-D-glucopyranosyl-β-D-glucopyranosyl)oxy]kaur-16-en-18-oic acid) 
  • CAS number 
    58543-17-2 
  • Chemical formula 
    C38H60O18
  • Molecular weight 
    804.88 

Rebaudioside C 

Rebaudioside C is one of the associated glycosides found in the stevia plant. It is generally present in preparations of Steviol glycosides at levels lower than stevioside or Rebaudioside A. 

  • Chemical name of Rebaudioside C 
    (13-[(2-O-6–deoxy-β-L-mannopyranosyl-3-O-β–D-glucopyranosyl-β-D-glucopyranosyl)oxy] kaur-16-en-18-oic acid β-D-glucopyranosyl ester) 
  • CAS number 
    63550-99-2
  • Chemical formula 
    C44H70O22 
  • Molecular weight 
    951.01 

Rebaudioside D 

Rebaudioside D is one of the associated glycosides found in the stevia plant. It is generally present in preparations of Steviol glycosides at levels lower than stevioside or Rebaudioside A. 

  • Chemical name of Rebaudioside D 
    (13-[2-O-β-D-glucopyranosyl-3-O-β-D-glucopyranosyl-β-D-glucopyranosyl]oxy]kaur-16-en-18-oic acid 2-O-β-D-glucopyranosyl-β-D-glucopyranosyl ester
  • CAS number 
    63279-13-0 
  • Chemical formula 
    C50H80O28 
  • Molecular weight 
    1129.15 

Rebaudioside E 

Rebaudioside E is one of the associated glycosides found in the stevia plant. It is generally present in preparations of Steviol glycosides at levels lower than stevioside or Rebaudioside A. 

  • Chemical name of Rebaudioside E 
    13-[[2-O-(β-D-Glucopyranosyl)-β-D-glucopyranosyl]oxy]kaur-16-en-18-oic acid 2-O-(β-D-glucopyranosyl)-β-D-glucopyranosyl ester 
  • CAS number 
    63279-14-1 
  • Chemical formula 
    C44H70O23 
  • Molecular weight 
    967.01 

Rebaudioside F 

Rebaudioside F is one of the associated glycosides found in the stevia plant. It is generally present in preparations of Steviol glycosides at levels lower than stevioside or Rebaudioside A. 

  • Chemical name of Rebaudioside F 
    13-[(2-O-β-D-xylofurananosyl-3-O-β-D-glucopyranosyl-β-D-glucopyranosyl)oxy]kaur-16-en-18-oic acid, β-D- glucopyranosyl ester 
  • CAS number 
    438045-89-7 
  • Chemical formula 
    C43H68O22 
  • Molecular weight 
    936.9 

Rebaudioside M 

Rebaudioside M is one of the associated glycosides found in the stevia plant. It is generally present in preparations of Steviol glycosides at levels lower than stevioside or Rebaudioside A. 

  • Chemical name of Rebaudioside M
    13-​[(O-​β-​D-​glucopyranosyl-​(1→2)​-​O-​[β-​D-​glucopyranosyl-​(1→3)​]​-​β-​D-​glucopyranosyl)​oxy]​-​, O-​β-​D-​glucopyranosyl-​(1→2)​-​O-​[β-​D-​glucopyranosyl-​(1→3)​]​-​β-​D-​glucopyranosyl ester
  • CAS number 
    1220616-44-3
  • Chemical formula 
    C56H90O33 
  • Molecular weight 
    1291.29

Rubusoside 

Rubusoside is one of the associated glycosides found in the stevia plant. It is generally present in preparations of Steviol glycosides at levels lower than stevioside or Rebaudioside A. 

  • Chemical formula of Rubusoside 
    13-[(β-D-Glucopyranosyl)oxy)kaur-16-en-18-oic acid β-D-glucopyranosyl ester 
  • CAS number 
    64849-39-4 
  • Chemical formula 
    C32H50O13
  • Molecular weight 
    642.73 

Steviol (Aglycone) 

Steviol (R1 = R2 = H) is the aglycone of the Steviol glycosides. 

Steviol Glycosides Chemical Formula 

This refers to the formula that describes the chemical composition of the Steviol glycoside molecules. 

In a standardized format, the atoms are listed followed by a number indicating the total number of those particular atoms in the molecule. For example the chemical formula for stevioside is: C38H60O18, whereas the chemical formula for Rebaudioside A is: C44H70O23, reflecting the fact that Rebaudioside A contains one more glucose molecule (C6H12O6) that is connected by an ester bond (loss of water H2O in the process). 

The chemical formula does not contain information about the chemical structure.   

Steviol glycosides chemical name 

Steviol glycosides is the name given to a particular class of glycosylated diterpenes that have a Steviol backbone and either combinations of glucose alone or glucose and rhamnose or xylose attached via an ester linkage. The diterpene known as Steviol is the aglycone of Stevia’s sweet glycosides. 

Steviol Glycosides Molar Mass 

This refers to the weight of a mole of an individual Steviol glycoside based on its chemical formula. For example, stevioside has the chemical formula C38H60O18, and therefore knowing the molar masses of each of the atoms listed and the numbers of each of the atoms in the molecule, the mole weight is 804.87, whereas Rebaudioside A, with a chemical formula of C44H70O23, has a mole weight of 967.01. 

Steviol Glycosides Structural Formula 

Representations of the chemical formulae, but with known bond positions and other spatial information depicted. The structural formula of the Steviol backbone and the types of additional sugar moieties for each of the Steviol glycosides is shown below (from Journal of Applied Glycoscience, Vol. 57 (2010), No. 3, pp.199-209):  

Name R1 R2 
Stevioside Glcβ1- Glcβ1-2 Glcβ1-  
Rebaudioside A    Glcβ1- Glcβ1-2(Glcβ1-3)Glcβ1- 
Rebaudioside B H- Glcβ1-2(Glcβ1-3)Glcβ1- 
Rebaudioside C  Glcβ1- Rhaα1-2(Glcβ1-3)Glcβ1- 
Rebaudioside D Glcβ1-2Glcβ1- Glcβ1-2(Glcβ1-3)Glcβ1- 
Rebaudioside E Glcβ1-2Glcβ1- Glcβ1-2Glcβ1- 
Rebaudioside F Glcβ1- Xylβ1-2(Glcβ1-3)Glcβ1 
Rebaudioside M  Glcβ1-2(Glcβ1-3)Glcβ1- Glcβ1-2(Glcβ1-3)Glcβ1-
Dulcoside A Glcβ1 Rhaα1-2Glcβ1- 
Rubusoside  Glcβ1- Glcβ1- 
Steviolbioside H- Glcβ1-2Glcβ1- 

Glc, Rha and Xyl represent, respectively, glucose, rhamnose and xylose sugar moieties. 

Steviolbioside 

Steviolbioside is one of the associated glycosides found in the stevia plant. It is generally present in preparations of Steviol glycosides at levels lower than stevioside or Rebaudioside A. 

  • The chemical name of Steviolbioside 
    (13-[(2-O-β-D-Glucopyranosyl-β-D-glucopyranosyl)oxy]kaur-16-en-18-oic acid) 
  • CAS number 
    41093-60-1
  • Chemical formula 
    C32H50O13 
  • Molecular weight 
    642.73   

Stevioside 

Stevioside is one of the Steviol glycosides found in the Stevia plant and is of principal interest for its sweetening property. 

  • Chemical name of Stevioside 
    13-[(2-O-β-D-glucopyranosyl-β-D-glucopyranosyl)oxy] kaur-16-en-18-oic acid, β-D-glucopyranosyl ester
  • CAS number 
    57817-89-7 
  • Chemical formula 
    C38H60O18 
  • Molecular weight 
    804.87 

Technical

Calibration 

Calibration is the empirical determination of the response of a detector or other equipment to a known input. For example, the detector response to a known compound in a sample where its concentration is unknown can be quantitated by determining the detector response relative to known amounts of the compound. This is routinely done in chromatographic analysis of the Steviol glycosides. 

HPLC 

High performance liquid chromatography (HPLC) is a standard analytical chromatographic method for separating and quantitating compounds that differ based on their chemical structure. 

Loss on drying 

A standard method for determining moisture in a sample.  The sample is typically weighed and then dried at 105°C for 2 hours and then re-weighed.  The loss of weight on drying is attributed to the moisture initially in the sample.  Another method for measuring the moisture content is using the Karl-Fisher method.

Nanometer 

Nanometer (nm) is a measure of length corresponding to 10-9 meters. 

Organic molecules typically absorb light with wavelengths in the 10 nm to 400nm range. 

UV 

UV or Ultra Violet refers to the wavelength in the light spectrum ranging from 10nm to 400nm and its absorption by organic molecules. 

It is routinely used to detect and quantify them.