9 research outputs found
Extraction and evaluation of natural occurring bioactive compounds and change in antioxidant activity during red winemaking
Phenolic composition of red wines from Stanušina, a grape variety indigenous of the Republic of Macedonia, was compared with the regional Vranec and the international Cabernet Sauvignon. The extent of skin contact (i.e. maceration time) on levels of phenolic compounds and antioxidant activity of wines was evaluated. A total of 19 phenolic compounds were identified and quantified. Among these malvidin-3-glucoside and its derivatives were the major compounds, while caftaric acid was the predominant cinnamic acid derivative, followed by catechin, the main flavan-3-ol. The concentration of hydroxycinnamic acids, anthocyanins and (+)-catechin ranged from 224 to 511 mg/L, 22 to 360 mg/L and 26 20 to 375 mg/L, respectively and peaked at 3rd, 6th and 9th day of maceration, respectively. However, prolong maceration slightly decreased their concentration. Stanušina wines presented high levels of hydroxycinnamic acids and antioxidant activity
Application of a Novel Small-Scale Sample Cleanup Procedure Prior to MALDI-TOF-MS for Rapid Pigment Fingerprinting of Red Wines
This study evaluates the anthocyanin and derived
pigment composition of
Vitis vinifera
red wines of Vranec,
Merlot, and Cabernet Sauvignon produced in 2006, 2007, and
2008 vintages from the Tikve
š
wine region in the Republic of
Macedonia.Their profile was established using matrix-assisted
laser desorption/ionization time-of-flight mass spectrometry
(MALDI-TOF-MS) technique. A total of 22 anthocyanins
and derived pigments have been identified in the samples including 10 anthocyanins, 1 ethyl-bridged flavanol
–
anthocy-
anin adduct, and 11 pyranoanthocyanins. MALDI-TOF-MS
analysis was performed after solid-phase extraction of the
wines by using, for the first time, the Zip-Tip® C18 stationary
phase, introducing a novel small-scale sample cleanup proce-
dure prior to the rapid MALDI-TOF-MS fingerprinting of
wine samples. 2
′
,4
′
,6
′
-Trihydroxyacetophenone (dissolved in
acetonitrile/water 1:1,
v
/
v
) was used as a matrix. The qualitative
screening of anthocyanins and derived pigments with MALDI-
TOF-MS confirmed the presence of glucoside, acetylglucoside,
and
p
-coumaroylglucoside derivatives of anthocyanins in the
wine samples. Furthermore, pyranoanthocyanins formed by
reactions of anthocyanins with pyruvic acid and acetaldehyde,
as well as flavanol
–
pyranoanthocyanins and ethyl-bridged
flavan-3-ol-anthocyanin adduct pigments have been detected
in the samples
Ultra-Performance Liquid Chromatography-Triple Quadruple Mass Spectrometry (UPLC-TQ/MS) for Evaluation of Biogenic Amines in Wine
In this study, a fast, simple, and sensitive analytical method for direct determination of biogenic amines tryptamine, putrescine, histamine, phenylethylamine, tyramine, cadaverine, spermine, and spermidine in wine has been developed and validated. Detection of analytes was performed with ultra-performance liquid chromatography (UPLC) coupled to triple quadruple mass spectrometer (TQ/MS). The calibration curves of all amines were linear with correlation coefficients (R2) ranging from 0.9906 for putrescine to 0.9998 for histamine and 2-phenyethylamine. The accuracy of the method was checked with a standard addition method, showing good accuracy, repeatability, and reproducibility (RSD < 10%). The limit of detection (LOD) and limit of quantification (LOQ) ranged from 0.50 to 30 μg/L and 1.50 to 90 μg/L, respectively, for all amines. The validated method was applied to detect and quantify biogenic amines in Macedonian red and white wines. Higher concentration of amines was observed in red wines (5797 μg/L, on average) compared to the white wines (1485 μg/L, on average)