Papers by Marius Niculaua
In the wine-making process, the yeasts form over 20 higher alcohols that improve the sensation of... more In the wine-making process, the yeasts form over 20 higher alcohols that improve the sensation of palatine veil for the wine. The amount of higher alcohols is lower for white and rosé wines obtained from clarified musts fermented at moderate temperatures. The formation of higher alcohols is confirmed by the fact that the addition of certain nitrogen compounds to a glucose-containing culture medium leads, after the fermentation, to an increase in the higher alcohol content. Data evaluate by comparison the levels of higher alcohols, esters and aldehydes, important to fermentation process in case of several wines from Panciu region. The wine-making was done by classical methods and by using specific protocols for low content sulphur dioxide. This study is focused to compare wines obtained from two grape varieties produced at industrial level: Feteasca regala vs. Feteasca regala Frizzante and Cabernet Sauvignon rosé vs. Cabernet Sauvignon. The compounds were analyzed by GC-FID method with head-space technique for methanol, 1-propanol, 2-methyl-propanol, 1-butanol, ethyl acetate, ethyl lactate, isoamyl acetate and acetaldehyde. The results showed that in almost every comparative study the levels of aroma compounds are maintained, when compared with the wines with low content of sulphur dioxide. Tuckey test showed that 1-propanol and ethyl acetate register statistically significant differences for Cabernet Sauvignon rosé and for Feteasca regala Frizzante.
Journal of Nutrition and Food Sciences, Dec 27, 2016
Lucrări Ştiinţifice, Universitatea de Ştiinţe Agricole Şi Medicină Veterinară "Ion Ionescu de la Brad" Iaşi, Seria Horticultură, 2009
BIO Web of Conferences
Ageing of wines on lees (autolysis) involves keeping wines in contact with dead yeast cells for s... more Ageing of wines on lees (autolysis) involves keeping wines in contact with dead yeast cells for several months/years to intensify the transfer of compounds between yeast cells and wine. During yeast autolysis, release of different compounds has been shown to have a positive influence on organoleptic characteristics of wine as these compounds, including lipids, mannoproteins, peptides, proteins, amino acids, and glucans, are breakdown products of yeasts and can impact on volatile profile of wine. The aim of this study was to evaluate the quality of white and rosé wines aged in contact with lees for 2 months, using 12 commercial maturation products. The studied wines were produced in Iasi vineyard, vintage 2020, from Sauvignon blanc and Busuioacă de Bohotin grapes variety. Thus, 26 samples were obtained (V1 SB-V13 SB; V1 BB – V13 BB). The effect of ageing on lees was assessed by analysing some main aroma compounds, performing an organoleptic analysis and quantifying color changes (CIE...
BIO Web of Conferences
Increasing the efficiency of the release for certain compounds during the maturation of some wine... more Increasing the efficiency of the release for certain compounds during the maturation of some wines in the presence of oak chips is an important topic for oenology research. This study followed the influence of the use of ultrasound waves with a frequency of 35 kHz on the physicochemical and sensory characteristics of some white wines from Iasi, Romania. Oak chips (1 g/L and 2 g/L, fresh, light, and medium toasted) were added to the Fetească regală and Sauvignon blanc stabilized wines. The samples were kept at a constant temperature of 15oC for 10 and 15 days, respectively. For comparison, 15 mins. ultrasound-treated samples were used. It has been observed that this technique in addition to reducing the aging time, significantly influences the organoleptic characteristics of the treated wines. New ways to continue research to clarify, optimize and streamline the methods of artificial aging of wines have also been identified.
Research Square (Research Square), Feb 13, 2023
This study aims to develop an HPLC analytical method, for separation, identi cation and quanti ca... more This study aims to develop an HPLC analytical method, for separation, identi cation and quanti cation of related substances and degradation products, in veterinary nished product with two active substances Enro oxacin (ENR) and Bromhexine hydrochloride (BRM). Analytical method used an Agilent Eclipse Plus C18 column (150 mm length x 4,6 mm I.D., 5 µm particle size) and a mobile phase consisted in a mixture of 2.5% phosphoric acid buffered at pH-2.3 with trimethylamine and acetonitrile in a gradient mode from 85% FMA to 55% FMA in 14,2 minutes, isocratic mode for 1 more minute and re-equilibration, total chromatographic time being 21 minutes. The method was developed in order to assure the separation of impurities speci c with ENR and BRM. Speci city in relation with degradation products revealed up to 20 impurities for ENR and 5 impurities related with BRM. The spectra of impurities were chosen among the compounds found in forced degradation studies. Method validation was performed according to VICH GL 2-Validation of analytical procedures and included selectivity/speci city, linearity, accuracy, precision, LOQ, LOD, robustness, system suitability. Under these conditions linearity was between 0.015-0.06 mg/mL for ENR and 0.001125-0.005625 mg/mL for BRM. Limit of quanti cation for ENR was 0.00292 mg/ml and 0.001103 mg/ml for BRM. These limits assured method performance because they are under the reporting threshold from VICH GL11 Impurities in new veterinary medicinal products which is 0.3%. Recovery was calculated on three concentrations for every compound and were 102.99% for ENR and 102.91% for BRM. In terms of intermediate precision, a relative maximum deviation of 2.5% was obtained for area and retention of the two compounds by using two analysts in two different days of application. This method used common and cheaper reagents and can separate and quantify, in a short time, all these compounds and is suitable to be used in quality control of the product.
Lucrări Științifice, Universitatea de Științe Agricole Și Medicină Veterinară "Ion Ionescu de la Brad" Iași, Seria Horticultură, 2017
“Ion Ionescu de la Brad” University of Agricultural Sciences and Veterinary Medicine, Iași, 2017
This study enhances knowledge in the physicochemical and color parameters of rosé wines produced ... more This study enhances knowledge in the physicochemical and color parameters of rosé wines produced by the prefermentative maceration of native Romanian 'Băbească neagră' (Vitis vinifera L.) grape varieties, both before and after tartaric stabilization treatments by the contact procedure in an MK70 ultra-refrigerator. One variety was prepared without maceration as a control sample and the other was subjected to the maceration process for one of the following seven periods of time: 3.5 hours, 7 hours, 10.5 hours, 14 hours, 17.5 hours, 21 hours and 24.5 hours. The prefermentative maceration process exerts a significant influence on the amount of volatile acids, on the pH, conductivity and the K+ cation. The phenolic compound content, the chromatic parameters and the cation content of wines are significantly influenced by both prefermentative maceration and tartaric stabilization. The multifactor ANOVA tests prove that there is an interaction for all parameters except for total ac...
ChemPlusChem, 2021
Bioinspired peptides are attractive biomolecules which can improve our understanding of self-asse... more Bioinspired peptides are attractive biomolecules which can improve our understanding of self-assembly processes for rational design of new peptide-based materials. Herein, a new amidated peptide FRSAPFIE (FRS), based on a sequence present in human collagen, was synthesized, characterized by mass spectrometry and subjected to self-assembling investigations. The optimal conditions for self-assembly were disclosed by dynamic light scattering at 32 °C and a peptide concentration of 0.51 %. In addition, AFM studies revealed ellipsoidal FRS shapes with an area between 0.8 and 3.1 μm2 . The ability of self-assembly was also proved using FAD dye as extrinsic fluorescence reporter. According to the theoretical analysis, the FRS peptide tends to form a bundle-type association, with a type of fibrillary tangles particle. Altogether, our findings address new challenges regarding the FRS peptide which can be used in further self-assembly studies to design biocompatible drug-delivery platforms.
Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca: Horticulture, 2013
In this study a number of seven prefermentative treatments were conducted in order to improve the... more In this study a number of seven prefermentative treatments were conducted in order to improve the compositional characteristics of certain wines obtained from TAƒmA¢ioasAƒ romA¢neascAƒ grape varieties. The samples were treated with: oxalic acid, lactic acid, succinic acid, ellagic tannins, bentonite, chitosan and oenological carbon. Folin-CiocA¢lteu index showed that the use of pre-fermentative treatments decreased the amount of phenolic compounds from 410.38 mg/L to 202,17 mg/L.Major color and hue differences for TAƒmA¢ioasAƒ romA¢neascAƒ wines are found in the samples treated with loxalic acid and activated carbon. Metal content revealed that bentonite treatment contributed at increasing the amount of sodium in wines. Calcium content increased due prefermentative treatments application from 10,67 mg/L to 41,29 mg/L. Coper conent was under detection limit of 0.01 mg/L (SLD <0.01 mg/L).
Free radicals have an important role in food and in chemical material degradation, contributing t... more Free radicals have an important role in food and in chemical material degradation, contributing to the occurrence of many human health problems. Highly reactive free radicals and oxygen species existing in biological systems can oxidize nucleic acids, proteins and lipids, starting degenerative diseases. Antioxidants can considerably delay or prevent the oxidation of easily oxidable substrates. Plants contain high concentrations of numerous bioactive constituents with antioxidant activity such as polyphenols. Flavonols, flavones, anthocyanidins and flavanols are reported to be found in significant quantities in wines. The experimental work involves the determination of antioxidant activity, expressed by the presence of these compounds, in several Romanian and Cypriot wines. In this paper work, the antioxidant activity quantification was carried out by the DPPH method. This spectrophotometric method is fast, simple and cheap and is based on the absorbance decrease determination of the...
The volatile aromas that are lost during the must's fermentation into wine represent a depart... more The volatile aromas that are lost during the must's fermentation into wine represent a department that is not very much analysed. The capturing and analysing of the volatile compounds that are trapped in the CO2 flow during gas exhaustion of the fermentation stage are the main objectives of the present study. The Tamaioasa romaneasca grapes, harvest of 2011, were processed according to the aromatic wine technology During fermentation, the volatile aromatic compounds were captured using SPE cartridges attached to the airlocks of the fermentation vessels. After the fermentation ended, the extracts were obtained by washing the bed of the SPE cartridges with 2 mL diclormethane. Gas-chromatography coupled with mass-spectrometry was used to identify the captured compounds. The processing technologies influenced the number and quantity of the captured compounds. Esters (isobutyl acetate) and alcohols, as well as aldehydes and terpenes are found in the exhaust air of the fermentation pr...
Journal of Food Science and Technology, 2020
Matching the general trend of replacing synthetic additives with healthier natural products, the ... more Matching the general trend of replacing synthetic additives with healthier natural products, the present research studies the effects of different concentrations of chokeberry extract which substitute carmoisine dye in jelly candies. Also, the colour and antioxidant properties of the aforementioned extract and their changes at various pH and in presence of different mineral salts from foods are analysed. The phenolic content of the extract was determined using HPLC and spectrophotometric methods. A high concentration of polyphenols was found in the chokeberry extract, of which around 97% were flavonoids. Catechin, epicatechin, ferulic acid and its methyl esther, protocatechuic, gallic and para -hydroxybenzoic acids were the major phenolics identified in the extract. The total antioxidant activity decreased in acidic media, while close-to-neutral and alkaline pH values did not exhibit any effect on this parameter. Furthermore, the green/red colour parameter, the chroma and the hue angle were enhanced in the most acidic media (pH 2.3 and 3.5). From the studied salts, CaCl 2 and KNO 3 had the most significant effects on colour. The chokeberry extract proved to be suitable as replacement of carmoisine dye in jelly candies, as the physicochemical and microbiological properties comply with the regulated requirements. More than that, the extract improved the antioxidant and sensory properties of jellies in all studied concentrations and the best total sensory score was obtained for 1.5% extract. After 5 and 50 days of storage, the microbiological properties were improved in candies prepared with aronia extracts compared to carmoisine, as the total viable count registered important diminutions.
BIO Web of Conferences, 2019
Most biochemical reactions involved in the wine-making process are catalyzed by enzymes. The use ... more Most biochemical reactions involved in the wine-making process are catalyzed by enzymes. The use of enzymes of exogenous origin in wine production is due to the numerous technological and economical advantages demonstrated over time in the winemaking process. Understanding the important role played by enzymes in wine making technology contributes to the development of optimization strategies for the production process to improve the final quality of the wine. In order to accomplish this study, the influence of five oenological preparations with pectolytic and β-glucosidases enzymes types on the volatile compounds of white wines obtained from Fetească regală variety was analyzed by monitoring their evolution during the alcoholic fermentation to the final product. Wine samples have been physically and chemically analysed (pH, acidity, alcoholic strength, density, malic acid, lactic acid, sugar content, SO2, total dry extract and non-reducing extract) according to OIV Standards. Separa...
Environmental Engineering and Management Journal, 2015
Wine analysis is a complex process, requiring multiple techniques and very in-depth multidiscipli... more Wine analysis is a complex process, requiring multiple techniques and very in-depth multidisciplinary knowledge. Moreover, when talking about sensorial potent wines, like Muscat or Tămâioasă Românească (from aromatic Romanian grape variety), the identification and characterization of its volatile compounds is achieved through different methods, most calling for powerful solvents to separate the aroma substances. Supercritical fluid extraction is a powerful technique with great promise in organic analytical chemistry. To date, little has been published on the use of SFE in the analysis of wine aromas. The main objective of this study is the analysis of volatiles in samples of Tămâioasă românească wines through a custom-made SFE method. The wine variants have been obtained by applying the general technological processes for aromatic wines, using specific oenological products. An in-house SFE analysis method was developed and applied, the obtained extracts were then analyzed by gas chromatography coupled to mass spectrometry (GC-MS) to identify the captured compounds. Regarding the total number of findings in respect to volatiles, the highest concentrations occur with low molecular weight alcohols, esters and acetic acid. Besides, there were also identified other volatile compounds, such as terpenoides and phenols. These specific compounds originate from the grape variety and give the "varietal" character to the wines.
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Papers by Marius Niculaua