Chemical Kinetics of 5-o-Caffeoylquinic Acid in Superheated Steam: Effect of Isomerization on Mate (Ilex paraguariensis) Manufacturing

Abstract

A set of experiments was carried out to investigate the chemical stability of 5-o-caffeoylquinic acid (5-CQA) in the presence of superheated steam. A batch cylindrical reactor made of glass and isothermally operated between 398 and 499 K was used in the experiments. A high-performance liquid chromatograph equipped with a diode array detector was applied to monitor the 5-CQA concentrations. The conversions of 5-CQA were correctly reproduced with a simplified kinetic model represented by a reversible pseudofirst-order reaction of isomerization. The effect of temperature on the forward rate constant was represented by the Arrhenius equation with parameters tuned on experimental data. The heat of isomerization of 5-CQA and the equilibrium constant at 298 K were calculated by involving the integrated form of the van't Hoff equation. The observed reaction was revealed to not be detrimental for the quality of manufactured leaves and branches of mate because the content of total chlorogenic acids was not changed.

A shrinking core model for slow combustion of solid 5-O-caffeoylquinic acid

“…At approximately this wavelength, 5-CQA was proved to present maximum absorbance [6,7,9,11,21,26,29]. Available HPLC analyses of 5-CQA submitted to conditions of oxidation almost identical to those adopted in the current investigation [7] support the reliability of the current kinetic results based on absorbance measurements.…”

“…Although the role of these components (ubiquitous in fruits, vegetables and herbs) in the protective mechanism at cellular level has been extensively studied [2], the impact of typical food processing operations at high temperature (such as drying, enzymatic deactivation, roasting) on the chemical antioxidant nature of these species has been a matter of minor interest [6][7][8][9]. However, the rate of oxidation of CGA during food manufacturing in the presence of air is of great importance because the oxygen drastically contributes to reduce the content of these species [9][10][11][12][13] naturally found in the food, and eventually the beneficial impact of their intake on human health.…”

“…It is also the single specie of this family that is available for market [3,19]. For these reasons, it is often used as a benchmark [20] to study the chemistry of CGA consumption due to chemical oxidation [7,11,21], enzyme action [8], pyrolysis [22][23][24][25] and heating in liquid water [12,26] or superheated steam [6].…”

Recent advances on Ilex paraguariensis research: Minireview

“…Dicaffeoylquinic acids (chlorogenic acids) and flavonoids showed the strongest effect (Zanoelo and Beninca, 2009). Along the same lines, a recent study in an animal model has shown that maté tea reduced acute lung inflammation in mice exposed to cigarette smoke.…”

Formation of inclusion compounds of (+)catechin with β-cyclodextrin in different complexation media: Spectral, thermal and antioxidant properties

“…As many other simple (chlorogenic, benzoic, cinnamic and coumaric acids) and polyphenol compounds (resveratrol, morin, quercetin) [5,6,[10][11][12], catechins (CATs) are antioxidants naturally found in plants, foods and drinks prepared from them [6,13,14]. CATs are also believed to present a protective role against cancer, viral infections and coronary diseases in humans that make them specially attractive for the food industry [6,15,13,14,16].…”