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

AZCARATE, SILVANA; GALINDO-IRANZO, PLÁCIDO; RASTALL, ROBERT A.; LEBRÓN-AGUILAR, ROSA; KOLIDA, SOFIA; MORENO, F. JAVIER; MUÑOZ-LABRADOR, ANA; QUINTANILLA-LÓPEZ, JESÚS E.; METHVEN, LISA; HERNANDEZ-HERNANDEZ, OSWALDO

Foods

Editorial Board

Año: 2020 vol. 9

To improve flavor profiles, three cyclodextrin glucosyltransferases (CGTases) from differentbacteriological sources, Paenibacillus macerans, Geobacillus sp. and Thermoanaerobacter sp., were usedwith an extract of steviol glycosides (SVglys) and rebaudioside A (RebA) as acceptor substratesin two parallel sets of reactions. A central composite experimental design was employed tomaximize the concentration of glucosylated species synthesized, considering temperature, pH,time of reaction, enzymatic activity, maltodextrin concentration and SVglys/RebA concentration asexperimental factors, together with their interactions. Liquid chromatography coupled to a diode-arraydetector (LC-DAD), liquid chromatography-mass spectrometry (LC-ESI-MS) and matrix-assisted laserdesorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) were used to characterizeand identify the chemical structures obtained along the optimization. To assess the impact on thesensory properties, a sensory analysis was carried out with a group of panelists that evaluated up to16 sensorial attributes. CGTase transglucosylation of the C-13 and/or C-19 led to the addition of up to11 glucose units to the steviol aglycone, which meant the achievement of enhanced sensory profilesdue to a diminution of bitterness and licorice appreciations. The outcome herein obtained supposesthe development of new potential alternatives to replace free sugars with low-calorie sweeteners withadded health benefits.