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conferenceseries.com
October 27-29, 2016 Rome, Italy
15th International Conference on
Food Processing & Technology
Volume 7, Issue 12 (Suppl) J Food Process Technol 2016
ISSN: 2157-7110 JFPT, an open access journal Food Technology 2016
October 27-29, 2016
Naturality and processing of stevia
Ursula Wolwer-Rieck and Anne Oehme
University of Bonn, Germany
Steviol glycosides, natural sweeteners of the shrub Stevia rebaudiana Bertoni, have been authorized in Europe as sweeteners with
a purity of more than 95%, since 2011. Their use is widespread worldwide in the food industry and is still growing as they are, in
contrast to high intensity artificial sweeteners, of natural origin and stable during food processing. Their manufacturing process is laid
down in the EU Regulation 1131/2011 and starts with hot water extraction of the dried leaves, followed by several purification steps
to remove further constituents of the plant. After crystallization and spray drying a white powder with a purity of 95% is obtained.
The purpose of this work was to show that all processing steps do not affect the chemical identity of steviol glycosides. Three different
sample batches provided by PureCircle, each containing the dried leaves, the first water extract and the end product with more than
95% purity of the same production batch were analyzed by UV-HPLC on a RP- and a HILIC-column as well. The USP-standard
containing nine steviol glycosides as described by JECFA (2010) was used as reference. It was possible to separate and identify eight
steviol glycosides on the RP-phase within seven minutes, while rebaudioside D was clearly detected on the HILIC-column. All of
the nine steviol glycosides required by JECFA were detected in the leaves, water extract and the 95% high purity end product of
each of the corresponding production batches. These data indicate that steviol glycosides are not affected and their chemical identity
modified by the manufacturing process, providing evidence for the naturality of high purity stevia leaf extract sweeteners.
Biography
Ursula Wolwer-Rieck has completed her PhD from Rheinische Friedrich-Wilhelms-Universität Bonn, Germany. She is a Food Chemist and tenured academic
Councilor in the Department of Nutrition and Food Sciences, University of Bonn. Her academic research is focused on steviol glycosides, the natural origin sweet
compounds of the stevia plant. She has published several papers on the analysis of steviol glycosides and their stability in food. She is also a board member of
the European Stevia Association (EUSTAS).
Ursula Wolwer-Rieck et al., J Food Process Technol 2016, 7:12 (Suppl)