Papers by Joanna Kolniak-Ostek
Journal of Food Composition and Analysis, 2016
Journal of Functional Foods, 2016
Journal of Food Processing and Preservation, 2016
Journal of Food Processing and Preservation, 2016
Journal of Liquid Chromatography & Related Technologies, 2016
Industrial Crops and Products, 2015
Journal of Agricultural and Food Chemistry, 2015
The aim of this study was to identify and compare the contents of phenolic acids, tannins, anthoc... more The aim of this study was to identify and compare the contents of phenolic acids, tannins, anthocyanins, and flavonoid glycosides in thorny and thornless blackberries. Five thorny and nine thornless cultivars were used for this study. Thirty-five phenolic compounds were determined in the examined fruits, and one phenolic acid, three ellagic acid derivatives, one anthocyanin, and six flavonols were characterized for the first time in blackberries. The thornless fruits were characterized by a higher content of anthocyanins (mean = 171.23 mg/100 g FW), ellagitannins (mean = 3.65 mg/100 g FW), and ellagic acid derivatives (mean = 2.49 mg/100 g FW), in comparison to thorny ones. At the same time, in thorny fruits, the contents of hydroxycinnamic acids (mean = 1.42 mg/100 g FW) and flavonols (mean = 5.70 mg/100 g FW) were higher.
Acta biochimica Polonica, Jan 26, 2016
In this paper, the extracts of three-part beggarticks (Bidens tripartita) were prepared using ult... more In this paper, the extracts of three-part beggarticks (Bidens tripartita) were prepared using ultrasonic assisted micelle-mediated extraction method (UAMME). Different kind of surfactants and WPC (whey protein concentrate) were applied. In the B. tripartita extracts twenty polyphenols were identified by UPLC-DAD-MS. Both aqueous and UAMME extracts mainly contained chlorogenic acid, caftaric acid and its derivatives as well as luteolin 7-O-glucoside. The luteolin was extracted with Rokanol B2 and Triton X-100. Furthermore, antioxidative properties of the extracts were analyzed with two methods: reactions with di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium (DPPH) reagent and Follin's method. The DPPH radical scavenging by micellar extracts was in general comparable with the antioxidant activity of conventional extracts. The most active was sample with Tego Care CG90, reducing about 73% of the radical. Obtained results confirmed that the UAMME might be an alternative method, to the ...
LWT - Food Science and Technology, 2016
Journal of Functional Foods, 2016
LWT - Food Science and Technology, 2015
LWT - Food Science and Technology, 2014
ABSTRACT The effects of storage duration and apple treatment by 1-MCP on yield, turbidity, cloud ... more ABSTRACT The effects of storage duration and apple treatment by 1-MCP on yield, turbidity, cloud stability, composition of phenolics and antioxidant activity were studied to evaluate the potential applicability of long-term stored apples in cloudy juice production. Main emphasis was given to the high molecular weight of procyanidins especially nonextractable polyphenols bonded to insoluble fiber fractions. juices were obtained from 'Idared', 'Shampion' and 'Topaz' apples cultivars after harvest (not stored), and after 2, 4, and 6 months of storage at 2 degrees C under normal atmosphere (NA). Juice yield in juices obtained from non-stored apples was between 69 and 76 g/100 g and successively during storage time decreased. The turbidity of obtained cloudy juices was from 540 to 2860 NTU (Nephelometric Turbidity Units). Total phenolic compounds content in apple juices produced from non-stored fruits was 794.5 mg/L in 'Idared', 882.2 mg/L in 'Shampion' and 683.0 mg/L in 'Topaz'. Total polyphenols in 'Idared' and 'Shampion' decreased after 6 months of storage. In 'Topaz' total polyphenolic content increased after storage. The content of procyanidins in insoluble fraction of juices obtained from non-stored apples was lower in comparison to juices after storage and was higher in juices obtained from apples treated with 1-MCP.
European Food Research and Technology, 2014
Journal of Agricultural and Food Chemistry, 2015
The aim of this study was to identify and compare the contents of phenolic acids, tannins, anthoc... more The aim of this study was to identify and compare the contents of phenolic acids, tannins, anthocyanins, and flavonoid glycosides in thorny and thornless blackberries. Five thorny and nine thornless cultivars were used for this study. Thirty-five phenolic compounds were determined in the examined fruits, and one phenolic acid, three ellagic acid derivatives, one anthocyanin, and six flavonols were characterized for the first time in blackberries. The thornless fruits were characterized by a higher content of anthocyanins (mean = 171.23 mg/100 g FW), ellagitannins (mean = 3.65 mg/100 g FW), and ellagic acid derivatives (mean = 2.49 mg/100 g FW), in comparison to thorny ones. At the same time, in thorny fruits, the contents of hydroxycinnamic acids (mean = 1.42 mg/100 g FW) and flavonols (mean = 5.70 mg/100 g FW) were higher.
Journal of Agricultural and Food Chemistry, 2014
The purpose of this research was to quantify and characterize phenolic compounds and to measure t... more The purpose of this research was to quantify and characterize phenolic compounds and to measure the antioxidant activity of Solanum scabrum and Solanum burbankii berries. The antioxidant activity of Solanum berry extracts was assayed by electrochemical and spectrophotometric methods, whereas liquid chromatography (LC)/quadrupole time-of-flight mass spectrometry and ultra-performance LC-photodiode detector were used for identification and quantification of their polyphenols. Eighteen phenolic compounds were identified in these fruits. The presence of seven phenolic acid derivatives and two flavonols was reported for the first time. In both cultivars, the major compound was found to be anthocyanin petunidin-3-(p-coumaroyl-rutinoside)-5-O-glucoside. Additional anthocyanins in S. burbankii and S. scrabum berries were characterized as petunidin, delphinidin, and malvidin with the same glycosidic substitution pattern and acylation with p-coumaric and ferulic acids. S. scabrum was richer in phenolic compounds, especially anthocyanins, and was characterized by more powerful antioxidant activity than S. burbankii .
Journal of Agricultural and Food Chemistry, 2013
The phenolic compounds were extracted from green and yellow leaves, stalks, and seeds of garlic (... more The phenolic compounds were extracted from green and yellow leaves, stalks, and seeds of garlic ( Allium ursinum L.). The extracts were analyzed by liquid chromatography-photodiode array detector-electrospray ionization-tandem mass spectrometry (LC-PDA-ESI-MS/MS). In total, 21 compounds were detected. The flavonol derivatives were identified on the basis of their ultraviolet (UV) spectra and fragmentation patterns in collision-induced dissociation experiments. On the basis of accurate MS and MS/MS data, six compounds were newly identified in bear's garlic, mainly the kaempferol derivatives. As far as the investigated parts of garlic are concerned, the kaempferol derivatives were found to be predominant in yellow leaves [2362.96 mg/100 g of dry matter (dm)], followed by green leaves (1856.31 mg/100 g of dm). Seeds contained the minimal phenolic compounds, less than stalks. The yellow leaves of A. ursinum possessed a much larger content of compounds acylated with p-coumaric acid than green leaves (1299.97 versus 855.67 mg/100 g of dm, respectively). The stalks and seeds contained much more non-acetylated than acetylated flavonoid glycosides with p-coumaric acid compounds (162.4 versus 62.82 mg/100 g of dm and 105.49 versus 24.18 mg/100 g of dm, respectively).
Industrial Crops and Products, 2013
ABSTRACT The effect of apple leaves addition on viscosity, turbidity, stability of turbidity, the... more ABSTRACT The effect of apple leaves addition on viscosity, turbidity, stability of turbidity, the composition of phenolics, antioxidant activity and color properties were studied to evaluate the potential application of leaves addition on cloudy apple beverages production. Beverages were obtained from ‘Šampion’ apples cultivar, after addition of 0.5%, 1% and 5%, respectively, of leaves.The viscosity of enriched beverages obtained after leaves addition ranged from 7.3% to 11.8%, and was significantly higher than the viscosity of the control sample, without the addition of leaves (6.6%). Higher turbidity and lower stability of turbidity was obtained upon leaves addition. The total content of phenolic compounds in apple beverages ranged between 1665 mg/L and 2541 mg/L and it was higher than in control juice (440 mg/L). Antioxidant capacity was positively correlated with content of polyphenolic compounds (correlation coefficient r = 0.63). According to HPLC–ABTS+ on-line analysis, the compounds of the flavan-3-ols group had the biggest impact on the antioxidant capacity value. Quercetin glycosides and dihydrochalcones, which are the main phenolics in leaves, influenced the antioxidant capacity to the minor and lesser extent, respectively.
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Papers by Joanna Kolniak-Ostek