Transglycosylation of Steviol Glycosides and Rebaudioside A: Synthesis Optimization, Structural Analysis and Sensory Profiles

• Published in: Foods Vol. 9; no. 12; p. 1753
• Main Authors: Muñoz-Labrador, Ana, Azcarate, Silvana, Lebrón-Aguilar, Rosa, Quintanilla-López, Jesús E, Galindo-Iranzo, Plácido, Kolida, Sofia, Methven, Lisa, Rastall, Robert A, Moreno, F Javier, Hernandez-Hernandez, Oswaldo
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 26.11.2020; MDPI
• Subjects: Bitterness; Calibration; CGTase; Chromatography; Cyclodextrin; Cyclodextrins; Design of experiments; Enzymatic activity; Enzymes; Experimental design; Flavor; Food additives; Food science; Glycosides; glycosylation; Ionization; Ions; licorice; Liquid chromatography; Maltodextrin; Mass spectrometry; Mass spectroscopy; Nitrogen; Obesity; Optimization; Particle size; Scientific imaging; Sensory evaluation; Sensory properties; Spectroscopy; Steviol glycosides; Structural analysis; Substrates; Sugar; sweetener; Sweeteners; Syrups & sweeteners; United Kingdom > UK; United States > US; rebaudioside A; bitterness; CGTase; glycosylation; Stevia rebaudiana; steviol glycosides; licorice; sweetener; design of experiments
• ISSN: 2304-8158; 2304-8158
• DOI: 10.3390/foods9121753

To improve flavor profiles, three cyclodextrin glucosyltransferases (CGTases) from different bacteriological sources, , sp. and sp., were used with an extract of steviol glycosides (SVglys) and rebaudioside A (RebA) as acceptor substrates in two parallel sets of reactions. A central composite experimental design was employed to maximize the concentration of glucosylated species synthesized, considering temperature, pH, time of reaction, enzymatic activity, maltodextrin concentration and SVglys/RebA concentration as experimental factors, together with their interactions. Liquid chromatography coupled to a diode-array detector (LC-DAD), liquid chromatography-mass spectrometry (LC-ESI-MS) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) were used to characterize and identify the chemical structures obtained along the optimization. To assess the impact on the sensory properties, a sensory analysis was carried out with a group of panelists that evaluated up to 16 sensorial attributes. CGTase transglucosylation of the C-13 and/or C-19 led to the addition of up to 11 glucose units to the steviol aglycone, which meant the achievement of enhanced sensory profiles due to a diminution of bitterness and licorice appreciations. The outcome herein obtained supposes the development of new potential alternatives to replace free sugars with low-calorie sweeteners with added health benefits.