Evaluation of nutritional and chemical composition of yacon syrup using 1H NMR and UPLC-ESI-Q-TOF-MSE

Abstract

A complete characterization of yacon syrup was performed by analytical techniques, including NMR and UPLC-QTOF-MS. The effect of the different stages of yacon syrup production on fructooligosaccharides (FOS) and chlorogenic acid (CGA) contents were also evaluated. As a result, in addition to higher levels of FOS and CGA, some mineral elements, such as K, Ca and P, and essential amino acids, such as tryptophan, valine, and threonine, were determined in yacon syrup. Twenty-five compounds were putatively identified, and the main compounds were phenolics derived from quinic and trans-cinnamic acids. Considering the different stages of yacon syrup production, the results indicate that the contents of FOS and CGA were maintained in the pulping, enzymatic maceration and microfiltration, leading to a concentration of these components in the last stage of processing (vacuum concentration). These results will be used to fortify this innovative and promising product in the area of functional foods.

Effect of yacon syrup on blood lipid, glucose and metabolic endotoxemia in healthy subjects: a randomized, double-blind, placebo-controlled pilot trial

“…Yacon syrup is a product obtained by enzymatic treatment, followed by microfiltration and vacuum concentration until it reaches a level of 71 °Brix (Silva et al, 2018a). This product contains high levels of FDS and phenolic compounds derived from quinic and trans-cinnamic acids (such as chlorogenic acid), and presents some mineral elements, such as K, Ca and P, and essential amino acids, such as tryptophan, valine, and threonine (Silva et al, 2018b). Moreover, we demonstrated in previous work, that yacon syrup administered as a diet supplement in women individuals showed a positive effect on appetite after a 2-week period of intervention (Silva et al, 2017).…”

“…The yacon syrup was produced in a pilot plant by Embrapa Tropical Agroindustry (Fortaleza -Ceara -Brazil). Onitially, after acid treatment of the yacon (Dionisio et al, 2013), the juice is extracted from the root, treated with Celluclast  1.5 L and Pectinex  Ultra SP-L (500 ppm of each enzyme, at 35 °C, 175 rpm, for 2 hours), and filtered in microfiltration system (Silva et al, 2018b). Thus, the clarified juice was concentrated under vacuum (< 60 °C) until it reached 71°Brix, and pH 3.7.…”

“…However, the understanding of the prebiotic relationship with glycemic, lipid and endotoxemia in human subjects is still scarce, and the results are contradictory and based, mostly, in the effect of isolated compounds (FDS, XDS, inulin, and others) and not as a complex matrix food, such as yacon syrup. The yacon syrup represents an alternative and convenient product to human diet consumption, presents high levels of bioactive compounds, especially FDS (Silva et al, 2018a), and is obtained from a process which comprises an acid and enzymatic treatment, followed by microfiltration and concentration (Silva et al, 2018b). After a short and medium-term intervention of this yacon syrup in healthy subjects (~ 8.74 g FDS/d), the results showed important sex-based differences in appetite responses to foods, with effects observed only in a medium-term intervention (Silva et al, 2017).…”

Feature-Based Molecular Networking to Target the Isolation of New Caffeic Acid Esters from Yacon (Smallanthus sonchifolius, Asteraceae)

“…Recent metabolomic studies suggest there is a wide diversity of caffeic acid esters in the different organs of yacon, although most of these accumulate in the roots [ 12 ]. For instance, several potentially new CAAs and caffeoyloctulosonic acids (COAs) have been observed in recent studies but were not characterized [ 12 , 13 , 14 ]. CAAs and COAs constitute two especially relevant chemical classes due to their medicinal properties and restricted distribution.…”

“…Apart from yacon, COAs and a few analogous compounds were identified in extracts of Erigeron breviscapus by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS), but their absolute configuration has not been determined [ 15 , 16 ]. Although the presence of additional caffeoyloctulosonic acid derivatives [ 13 ] and undescribed caffeoylaltraric acids has been recently suggested in yacon [ 12 ], their chemical structures are not yet formally characterized.…”