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Impact of storage conditions on the aromatic profile of virgin olive oils : bachelor thesis
No full textMaslina (Olea europea) jedna je od najstarijih kultiviranih biljaka i ključna kultura u jadranskom dijelu Hrvatske. Djevičanska maslinova ulja, proizvedena isključivo mehaničkim postupcima tiještenja zdravih plodova masline, izdvajaju se svojim jedinstvenim sastavom i aromom. Hlapljivi spojevi koji se razvijaju tijekom i nakon ekstrakcije ulja značajno doprinose njegovom aromatičnom profilu. Osim berbe i prerade, na kvalitetu maslinovog ulja utječu adekvatna dorada i pravilno skladištenje, što je ključno za očuvanje ulja i zaštitu od štetnih vanjskih utjecaja. Cilj ovog Završnog rada bio je ispitati utjecaj načina čuvanja djevičanskog maslinovog ulja, dobivenog preradom različitih sorti maslina (Oblica, Leccino i Levantinka) ubranih s dva različita lokaliteta, na aromatični profil ulja. Uzroci su čuvani na tri načina: u tamnoj staklenoj boci na suhom i tamnom mjestu, u inox spremniku te u inox spremniku s dušikom u natprostoru. Analize su provedene svako 6 mjeseci u periodu od 18 mjeseci. Iz dobivenih rezultata utvrđeno je da odabir načina čuvanja ima izražen utjecaj na aromatični profil djevičanskih maslinovih ulja. Rezultati svih načina čuvanja ulja pokazali su blagi trend pada hlapljivih spojeva koji se povezuju pozitivnim aromama. Čuvanje ulja u tamnoj staklenoj boci i inox spremnicima s dušikom u natprostoru se pokazalo kao izrazito dobar način čuvanja, naročito za sprječavanja procesa oksidacije. Ulja čuvana u inox spremniku bez korištenja dušika u natprostoru bila su podložnija procesima oksidacije što je rezultiralo povećanim udjelom hlapljivih spojeva koji se povezuju s negativnim aromama ulja.The olive (lat. Olea europea) is one of the oldest cultivated plants and a key crop in the Adriatic region of Croatia. Virgin olive oils, produced exclusively through mechanical processes by pressing healthy olive fruits, stand out due to their unique composition and aroma. The volatile compounds that develop during and after the oil extraction significantly contribute to its aromatic profile. In addition to harvesting and processing, the quality of olive oil is influenced by appropriate refinement and proper storage, which are crucial for preserving the oil and protecting it from harmful external factors. The aim of this thesis was to investigate the impact of storage methods on the aromatic profile of virgin olive oil obtained from the processing of different olive varieties (Oblica, Leccino, and Levantinka) harvested from two different locations. The samples were stored in three different ways: in a dark glass bottle in a dry and dark place, in a stainless steel tank, and in a stainless steel tank with nitrogen in the headspace. Analyses were conducted every six months over a period of 18 months. The results indicated that the choice of storage condition has a significant effect on the aromatic profile of the virgin olive oil. The results of all methods of oil storage showed a slight trend of decreasing volatile compounds associated with positive aromas. Storing the oil in a dark glass bottle and in nitrogen-filled stainless steel tanks proved to be an extremely effective way to preserve the oil, particularly in preventing oxidation processes. In contrast, oils stored in a stainless steel tank without using nitrogen in the headspace were more susceptible to oxidation processes, which resulted in an increased proportion of volatile compounds that are associated with the negative aromas of the oil
Preparation and characterization of natural zeolite clinoptilolite coated with sulfide species - determination of the selectivity of the prepared sample towards Hg(II) in relation to other divalent heavy metal cations : diplom athesis
No full textPrirodni zeolit klinoptilolit obložen sulfidnim specijama (SZ-25) dobiven je kemijskom modifikacijom prirodnog zeolita (PZ) klinoptilolita s Na 2 S pri 25 °C. Svrha modifikacije zeolita bila je poboljšati sorpciju Hg(II). Klasična kemijska analiza, kisela i bazična svojstva određena Bohemovom metodom, kemijsko ponašanje pri različitim pH o vrijednostima, zeta potencijal pri različitim pH o vrijednostima, specifična površina, rendgenska difrakcijska analiza praškastog uzorka (XRPD), pretražna elektronska mikroskopija s energijsko disperzivnom rendgenskom spektroskopijom (SEM-EDS), infracrvena spektroskopija s Fourierovom transformacijom (FTIR) kao i termogravimetrijska analiza (TG-DTG) korišteni su za detaljnu komparativnu mineralošku i fizikalno-kemijsku karakterizaciju PZ i SZ-25. Rezultati su pokazali da je površina SZ-25 uspješno obložena sulfidnim specijama u obliku FeS i CaS. Kemijska modifikacija uzrokovala je povećanje bazičnosti i ukupnog negativnog naboja površine zbog povećanja funkcionalnih skupina koje sadrže kisik te smanjenje specifične površine i kristaliničnosti zbog stvaranja nakupina koje sadrže sumpor na površini zeolita. Modificirani uzorak, SZ-25 pokazao je iznimnu selektivnost prema Hg(II) u odnosu na ostale dvovalentne katione teških metala. Utvrđen je sljedeći redoslijed selektivnosti: Hg > Pb > Cd > Zn > Cu > Ni > Co > Mn. Na temelju dobivenih rezultata, modificirani uzorak se čini izvrsnim izborom za sanaciju područja onečišćenih živom.Natural zeolite clinoptilolite coated with sulfide species (SZ-25) was obtained by chemical modification of natural zeolite clinoptilolite (PZ), with Na 2 S at 25 °C. The purpose of the zeolite modification was to improve the sorption of Hg(II). Chemical analysis, acid and basic properties determined by Bohem’s method, chemical behavior at different pH o values, zeta potential, cation- exchange capacity (CEC), specific surface area, X-ray powder diffraction (XRPD), scanning electron microscopy with energy-dispersive X-ray analysis (SEM-EDS), Fourier transform infrared spectroscopy (FTIR), as well as thermogravimetry (TG-DTG) were used for detailed comparative mineralogical and physico-chemical characterization of PZ and SZ-25. The results showed that the surface of SZ-25 was successfully coated with sulfide species in the form of FeS and CaS. Chemical modification caused an increase in basicity and total negative surface charge due to an increase in functional groups containing oxygen and a decrease in specific surface area and crystallinity due to the formation of clusters containing sulfur on the zeolite surface. The modified sample, SZ-25, showed exceptional selectivity towards Hg(II) in relation to other divalent heavy metal cations. The order of selectivity was determined as follows: Hg > Pb > Cd > Zn > Cu > Ni > Co > Mn. Based on the obtained results, the modified sample appears to be an excellent choice for the remediation of mercury-contaminated sites
Aromatic profile of Ninski šokol : diploma thesis
No full textNinski šokol je jedinstveni gastronomski proizvod jedinstvene arome, koji ima dugu tradiciju proizvodnje u gradu Ninu i širem okolnom području. Za izradu ninskog šokola vrlo važno je kvalitetno svinjsko meso, ninska sol, razni začini i tradicijski proces proizvodnje. Specifičnosti sirovine, tehnološkog postupka pripreme i zrenja rezultiraju povećanjem koncentracije hlapljivih spojeva arome. Te su komponente proizašle iz biokemijskih procesa prilikom razgradnje masnog, vezivnog i mišićnog tkiva a odgovorne su za specifična okusna i mirisna obilježja ovog proizvoda. Hlapljivi spojevi su izolirani metodom mikroekstrakcije vršnih para na krutoj fazi (HS-SPME), korištenjem triju vlakana različite polarnosti. Izolirani spojevi su analizirani spregnutom tehnikom plinska kromatografija – spektrometrija masa (GC- MS) u cilju usporedbe sličnosti i razlika dobivenih rezultata. Ukupno je identificirano 38 spojeva koji se mogu svrstati u kemijske skupine: aldehide, alkohole, alkane, estere, fenole, masne kiseline i terpene.Ninski šokol is a distinctive gastronomic meat product with an unique aroma, produced for centuries in the town of Nin and its surrounding areas. Its preparation relies on high-quality pork, local salt from Nin, various spices and traditional methods, which are crucial for achieving its distinctive flavor. The specific qualities of the raw materials and the aging process lead to a higher concentration of volatile aromatic compounds. These compounds are result of biochemical processes that occur during the breakdown of fat, connective and muscle tissues, contributing to the unique taste and aroma of the product. The volatile compounds were isolated using headspace solid-phase microextraction (HS- SPME) with three fibers of different polarities. The extracted compounds were analyzed using gas chromatography-mass spectrometry (GC-MS) to compare the similarities and differences in the results. A total of 38 compounds were identified, categorized into the chemical groups such as aldehydes, alcohols, alkanes, esters, phenols, fatty acids, and terpenes, further highlighting the complexity and richness of Ninski šokol
Corrosion inhibition of titanium by propolis in simulated oral cavity conditions : diploma thesis
No full textTitanij (Ti) je zbog svoje visoke otpornosti na koroziju, izvanredne biokompatibilnosti, mogućnosti repasivacije i odgovarajućih mehaničkih svojstava postao standardni materijal za izradu dentalnih implantata. Korozijska otpornost ovog materijala povezana je s prisutnošću zaštitnog oksidnog sloja na površini. Međutim, usna šupljina predstavlja složenu sredinu koja može negativno utjecati na korozijsku otpornost, dugotrajnost i integritet titanijskih implantata. Jedna od često primjenjivanih metoda zaštite metala od korozije je zaštita metala inhibitorima korozije. U ovom radu istraživan je utjecaj etanolnog ekstrakta propolisa na korozijsko ponašanje titanija u simuliranim uvjetima usne šupljine pri različitim temperaturama. Istraživanja su provedena elektrokemijskim metodama (metoda mjerenja potencijala otvorenog kruga, metoda linearne polarizacije i potenciodinamička polarizacijska metoda). Nakon slijeda elektrokemijskih mjerenja površinski slojevi Ti analizirani su optičkim mikroskopom, a dodatna analiza elektrolitnih otopina i površinskih slojeva Ti provedena je infracrvenom spektroskopijom s Fourierovom transformacijom tehnikom univerzalne prigušene totalne refleksije (FTIR-UATR). Dobiveni rezultati pokazuju kako je etanolni ekstrakt propolisa mješoviti inhibitor korozije Ti u simuliranim uvjetima usne šupljine. Najveća inhibitorska djelotvornost 78 % postignuta je pri 36 °C, a povećanjem temperature inhibitorska djelotvornost se smanjuje. Izračunate energije aktivacije i termodinamički aktivacijski parametri ukazuju na to da se inhibicija korozije Ti etanolnim ekstraktom propolisa odvija fizisorpcijom, a proces adsorpcije je endoterman. Metodom FTIR-UATR u slojevima na površini uzoraka Ti identificirane su funkcionalne skupine prisutne u propolisu.Titanium (Ti) has become the standard material for dental implants due to its high corrosion resistance, excellent biocompatibility, repassivation ability, and suitable mechanical properties. The corrosion resistance of this material is related to the presence of a protective oxide layer on its surface. However, the oral cavity is a complex environment that can adversely affect titanium implants' corrosion resistance, longevity and integrity. One of the most commonly applied methods for protecting metals from corrosion is the use of corrosion inhibitors. In this study, the effect of ethanolic propolis extract on the corrosion behavior of titanium in simulated oral cavity conditions at different temperatures was investigated. The research was conducted using electrochemical methods (open circuit potential measurement method, linear polarization, and potentiodynamic polarization method). Following a sequence of electrochemical tests, an optical microscope was used to analyze the Ti surface layers. After that, the electrolyte solutions and the Ti surface layers were further examined using Fourier transform infrared spectroscopy employing universal attenuated total reflectance (FTIR-UATR). The results indicated that an ethanolic propolis extract acts as a mixed-type corrosion inhibitor for Ti under simulated conditions in the oral cavity. The maximum inhibitory efficiency of 78 % was achieved at 36 °C; the inhibitory efficiency decreases with increasing temperature. The determined activation energies and thermodynamic activation parameters show that an ethanolic propolis extract inhibits the corrosion of Ti by physisorption with an endothermic adsorption process. The functional groups present in the propolis were identified in the layers on the surface of the Ti samples using the FTIR-UATR method
Metabolomic study: identification of hexadecanal as a potential biomarker for preeclampsia : diploma thesis
No full textU ovom diplomskom radu provedena je ne-ciljana metabolomička analiza hlapljivih organskih metabolita u uzorcima urina trudnica s ciljem pronalaska i identifikacije potencijalnih biomarkera preeklampsije – ozbiljnog metaboličkog poremećaja koji se javlja tijekom trudnoće. Ukupno je analiziran 91 uzorak urina, od čega je 45 uzoraka pripadalo trudnicama s dijagnosticiranom preeklampsijom, a ostalih 46 uzoraka zdravih trudnica služilo je kao kontrolna skupina. Kemijska analiza temeljena je na mikroekstrakciji vršnih para na krutoj fazi u kombinaciji s vezanim sustavom plinske kromatografije i spektrometrije masa (HS-SPME/GC-MS), nakon čega je uslijedila obrada podataka i statistička analiza kako bi se identificirali statistički značajni metaboliti. Provedba ove opsežne metabolomičke studije rezultirala je identifikacijom ukupno 29 hlapljivih metabolita u obje ispitivane skupine uzoraka, pri čemu se heksadekanal istaknuo kao statistički najznačajniji spoj povezan s preeklampsijom. Analiza biomarkera pokazala je obećavajući dijagnostički potencijal heksadekanala, dok je analiza obogaćenja istaknula njegovu povezanost sa metabolizmom sfingolipida. Stoga ova studija pozicionira heksadekanal kao potencijalni neinvazivni biomarker preeklampsije, pružajući novi uvid u metaboličke poremećaje koji stoje u pozadini patofiziologije ovog ozbiljnog zdravstvenog stanja.In this thesis, an untargeted metabolomics analysis of volatile organic metabolites in urine samples from pregnant women was conducted. The aim of it was identifying potential biomarkers for preeclampsia – a serious metabolic disorder that occurs during pregnancy. A total of 91 urine samples were analyzed, 45 of which belonged to pregnant women diagnosed with preeclampsia, while the remaining 46 samples from healthy pregnant women served as the control group. The chemical analysis was based on solid-phase microextraction of headspace vapor, combined with gas chromatography-mass spectrometry (HS- SPME/GC-MS), followed by data processing and statistical analysis to identify statistically significant metabolites. This comprehensive metabolomics study resulted in the identification of 29 volatile organic metabolites across both groups, with hexadecanal standing out as the most statistically significant compound associated with preeclampsia. Biomarker analysis demonstrated the promising diagnostic potential of hexadecanal, while enrichment analysis highlighted its connection to sphingolipid metabolism. Therefore, this study positions hexadecanal as a potential non-invasive biomarker for preeclampsia, providing fresh insights into the metabolic disturbances underlying the pathophysiology of this serious health condition
LEAD REMOVAL FROM WASTEWATER USING BY-PRODUCTS/WASTE FROM THE FOOD INDUSTRY : diploma thesis
No full textSve veći porast gradskog stanovništva, razvoj industrije i energetike, povećanje komunalnog otpada i razvoj masovnog turizma dovode do emisije štetnih metala u okoliš. Navedeni antropogeni izvori znatno onečišćuju vode u prirodi teškim metalima, stoga je neophodno razviti metode uklanjanja teških metala iz vode na siguran i ekološki prihvatljiv način. U ovom radu ispitana je učinkovitost uklanjanja teškog metala olova iz otpadne vode sorpcijom na nusproizvodima/otpadu iz prehrambene industrije (košticama maslina, peletu od komine maslina, ostacima hridinskog ježinca, košticama trešanja i košticama višanja). Sorpcija olova provedena je šaržnim postupkom iz otpadne vode koncentracije 0,5 mmol Pb/L i 1,5 mmol Pb/L. Svi ispitani biosorbensi pokazali su potencijal uklanjanja olova iz obiju otpadnih voda. Bolje uklanjanje olova postignuto je pri nižoj početnoj koncentraciji. Najveću učinkovitost pokazale su koštice višanja i to 83,65 % pri nižoj početnoj koncentraciji olova te 54,90 % pri višoj početnoj koncentraciji. Iako je postignuto prilično dobro uklanjanje olova iz otpadne vode, zaostala koncentracija olova bila je iznad zakonom propisanih vrijednosti za ispust efluenta u površinske vode i u sustav javne odvodnje. Stoga bi buduća istraživanja trebalo usmjeriti na modifikaciju ispitanih biosorbenasa radi povećanja njihove učinkovitosti u obradi voda onečišćenih olovom.Increase in the city's population, the development of industry and energetics, the increase in municipal waste and the development of mass tourism lead to the emission of harmful metals into the environment. The mentioned anthropogenic sources significantly pollute water in nature with heavy metals, thus it is necessary to develop methods of removing heavy metals from water in a safe and environmentally friendly manner. In this diploma thesis the effectiveness of lead removal from wastewater by sorption using by-products/waste from the food industry (olive pits, olive pomace pellets, residues of the sea urchin, cherry pits and sour cherry pits) was examined. Sorption of lead was carried out by a batch performance from wastewater containing 0.5 mmol Pb/L and 1.5 mmol Pb/L. All tested biosorbents showed the potential for lead removal from both wastewaters. Better removal was achieved at lower initial lead concentration. The highest efficiency of 83.65 % was obtained by sour cherry pits for lower initial lead concentration and 54.90 % for higher initial lead concentration. Although a good lead removal was achieved, the residual lead concentration was still above the prescribed value for discharge into the public sewage system and into the surface waters. Therefore, future research should be focused on the modification of the tested biosorbents in order to increase their efficiency in treatment of lead polluted water
Equilibrium adsorption of copper ions from copper (II) nitrate on humus : diploma thesis
No full textU ovom diplomskom radu ispitivana je ravnoteža adsorpcije bakrovih iona iz otopina bakrovih iona različitih početnih koncentracija na humusu u šaržnom reaktoru pri stalnoj temperaturi od 308 K, brzini miješanja od 200 okr min-1 te trajanju eksperimenta od 96 h. Porast početnih koncentracija otopine bakrovih iona ne utječe značajno na ravnotežnu koncentraciju adsorbiranih bakrovih iona na humusu jer se ona neznatno mijenja. Maksimalni kapacitet adsorpcije bakrovih iona na humusu postignut je pri koncentraciji od 8,016 mmol dm-3 te iznosi 0,518 mmol g-1 za zadane uvjete provedbe eksperimenta. Učinkovitost adsorpcije bakrovih iona na humusu opada s porastom početne koncentracije bakrovih iona te je maksimalan učinak adsorpcije bakrovih iona na humusu postignut pri najnižoj odabranoj početnoj koncentraciji od 4,049 mmol dm-3 i iznosi 60,320 %. Dobiveni eksperimentalni podatci testirani su Langmuirovom, Freundlichovom, Tothovom, Redlich-Petersonovom i Sipsovom izotermom. Procjenom kvalitete slaganja adsorpcijskih modela s eksperimentalnim podatcima, usporedbom izračunatih vrijednosti statističkih parametara za RMSE i χ2 te maksimuma kapaciteta adsorpcije i eksperimentalno dobivenog može se zaključiti da najbolje slaganje s eksperimentalnim podatcima pokazuje Tothova izoterma koja je razvijena kako bi proširila primjenu Langmuirovog modela u heterogenim sustavima.In this diploma thesis, the equilibrium adsorption of copper ions from the copper ions solutions of various initial concentrations was investigated in a batch reactor on the humus at a constant temperature of 308 K, a stirring speed of 200 rpm for 96 h. The increase in the initial concentrations of copper ions solutions does not significantly affect on the equilibrium amount of copper ions adsorbed on the humus because it slightly changes. The maximum adsorption capacity of copper ions on the humus was achieved at a concentration of 8.016 mmol dm-3 with the value of 0.518 mmol g-1 for the given experimental conditions. The adsorption efficiency of copper ions on the humus decreases with an increase in the initial concentration of copper ions, and the maximum adsorption capacity of copper ions on the humus was achieved at the lowest selected initial concentration of 4.049 mmol dm-3 with the value of 60.320 %. The experimental data obtained were tested on Langmuir, Freundlich, Toth, Redlich-Peterson and Sips isotherms. By estimating the quality of the agreement of adsorption models with the experimental data, comparing the calculated values of statistical parameters for RMSE and χ2 and the maximum adsorption capacity with the experimentally obtained, it can be concluded that the best agreement with experimental data is shown by the Toth isotherm, which was developed to extend the application of the Langmuir model in heterogeneous systems
Impact of different drying methods on the stability of anthocyanins from cultivated blueberry (VACCINIUM CORYMBOSUM L) : diploma thesis
No full textKultivirana borovnica (Vaccinium corymbosum L.) smatra se jednim od najznačajnijih komercijalnih predstavnika roda Vaccinium. U Hrvatsku je stigla iz Sjedinjenih Američkih Država i smatra se introduciranom vrstom. Kultivirana borovnica ima dobre nutritivne značajke (dobar sklad makro i mikronutrijenata), ali i senzorske karakteristike (ugodna boja, aroma i okus). Prisutnost biološki aktivnih komponenti, prije svega fenolnih spojeva, daje dodatnu vrijednost ovoj namirnici. S obzirom na brojnost i zdravstveni aspekt, treba istaknuti antocijane kao najbitnije predstavnike fenolnih spojeva prisutnih u kultiviranoj borovnici. U ovom radu ispitan je utjecaj različitih postupaka sušenja: liofilizacija uz postepeno smrzavanje (– 80 C) i naglo smrzavanje (- 196 C), vakuum sušenje i konvekcijsko sušenje na stabilnost fenolnih spojeva. Osušeni plodovi kultivirane borovnice samljeveni su uz pomoć mlina s noževima. Ukupni fenoli u svježim i osušenim uzorcima određeni su uz pomoć spektrofotometrijske metode koristeći Folin-Ciocalteu reagens. Analiza fenolnih spojeva iz svježih i osušenih uzoraka urađena je uz pomoć tehnike visoko djelotvorne tekućinske kromatografije (HPLC) s foto- diodnim detektorom (DAD). Negativan utjecaj sušenja na polifenole manifestirao se kroz smanjenje sadržaja ukupnih i pojedinačnih fenolnih spojeva prisutnih u plodu kultivirane borovnice. Metoda sušenja liofilizacijom, uz prethodno naglo smrzavanje plodova borovnice u tekućem dušiku pri - 196 C, izazvala je najmanji gubitak fenolnih spojeva i stoga se smatra najprikladnijom metodom za sušenje, dok je liofilizacija uz postepeno smrzavanje pri – 80 C ostvarila nešto veće gubitke fenolnih spojeva. Najveće gubitke polifenola pretrpjeli su uzorci podvrgnuti konvekcijskom sušenju.Cultivated blueberry (Vaccinium corymbosum L.) is considered one of the most important commercial representatives of the genus Vaccinium. It arrived in Croatia from the United States of America and is considered an introduced species. Cultivated blueberry has good nutritional characteristics (good balance of macro and micronutrients) and sensory characteristics (pleasant color, aroma and taste). The presence of biologically active components, primarily phenolic compounds, gives additional value to this food. Considering the abundance and health aspect, anthocyanins should be highlighted as the most important representatives of phenolic compounds present in cultivated blueberry. In this work, the influence of different drying procedures: freeze-drying with gradual freezing (-80 C) and flash freezing (- 196 C), vacuum drying and convective drying on the stability of phenolic compounds was examined. The dried fruits of the cultivated blueberry were ground with the help of a knife mill. Total phenolics in fresh and dried samples were determined using the spectrophotometric method using the Folin-Ciocalteu reagent. The analysis of phenolic compounds from fresh and dried samples was carried out using the technique of high-performance liquid chromatography (HPLC) with a photo-diode detector (DAD). The negative impact of drying on polyphenols was manifested through a decrease in the content of total and individual phenolic compounds present in the fruit of the cultivated blueberry. The freeze-drying technique, with previous flash freezing of blueberry fruits in liquid nitrogen at - 196 C, caused the least loss of phenolic compounds and is therefore considered the most suitable method for drying, while freeze-drying with gradual freezing at - 80 C achieved slightly higher losses of phenolic compounds. Samples subjected to convection drying had the greatest loss of polyphenols
Volatile compounds profile of scottish liqueuer Drambuie : diploma thesis
No full textDrambuie je tradicionalni liker od škotskog viskija, s dodatkom meda od vrijeska te začinskog i aromatičnog bilja. Receptura ovog likera odnosno udio pojedinih sastojaka je karakteristična za samog proizvođača. Specifičan okus i aroma ovog likera očituje se kroz posebnost korištenih sirovina, te niz biokemijskiih reakcija koje se odvijaju tijekom tehnološkog procesa proizvodnje posebice tijekom odležavanja i zrenja. Za izolaciju hlapljivih spojeva likera korištene su dvije metode: mikroekstrakcija vršnih para na krutoj fazi (HS-SPME) uz upotrebu tri vrste vlakana (plavo, roza i sivo) te ekstrakcija tekuće-tekuće pri čemu je korištena smjesa različitih organskih otapala (smjesa pentan:dietil-eter (1:2, v/v) i diklormetan). Analiza hlapljivih spojeva je izvršena vezanim sustavom plinska kromatografija-masena spektrometrija (GC-MS). Najzastupljeniji izolirani spojevi pripadaju višim alkoholima, esterima i terpenima.Drambuie is a traditional Scotch whisky liqueur, with the addition of heather honey and spices and aromatic herbs. The recipe of this liqueur, or the proportion of individual ingredients, is characteristic of the manufacturer. The specific taste and aroma of this liqueur is manifested through the uniqueness of the raw materials used, and a series of biochemical reactions that take place during the technological production process, especially during aging and ripening. Two methods were used to isolate the volatile compounds of the liqueur: headspace solid-phase microextraction method (HS-SPME) using three types of fibers (blue, pink and gray) and liquid-liquid extraction using a mixture of different organic solvents (a mixture of pentane:diethyl ether (1:2, v/v) and dichloromethane). The analysis of volatile compounds was performed using a coupled gas chromatography-mass spectrometry (GC-MS) system. The most abundant isolated compounds belong to higher alcohols, esters and terpenes
Physicochemical analysis and aromatic profile of unifloral honey varieties : diploma thesis
No full textU ovom radu analiziran je fizikalno-kemijski sastav i aromatični profil pet različitih vrsta meda (med od: drače, kadulje, pajasena, planike i vriska). Od fizikalno-kemijskih parametara određivan je pH, udjel vode i električna provodnost. Također je određena i melisopalinološka analiza te spektralna analiza šećera. FTIR analizom utvrđeno je da med od kadulje i pajasena sadrži najviši udio fruktoze, dok je njen najmanji udio bio kod meda od planike. Hlapljivi spojevi meda izolirani su mikroekstrakcijom vršnih para na krutoj fazi (HS-SPME) koristeći sivo vlakno te analizirani vezanim sustavom plinska kromatografija – spektrometrija masa. Hlapljivi spojevi sa najvišim udjelom su: benzaldehid, 2-furankarboksaldehid (furfural), 2-fenilacetaldehid, 4-metoksi benzaldehid, linalol, trans-linalol oksid (furanski tip), izomeri aldehida jorgovana, nonanol, 2,3,5-trimetilpirazin. 5-hidroksimetilfurfural (HMF) identificiran je samo u medu od planike, dok su metil-siringat i metil salicilat identificirani samo u medu od vriska.In this paper, the physicochemical composition and aromatic profile of five different types of honey (honey from: spiny broom, sage, tree of heaven, strawberry tree and savory) were analyzed. The physicochemical parameters determined were pH, water content, and electrical conductivity. Additionally, melissopalynological analysis and spectral analysis of sugars were conducted. FTIR analysis revealed that sage and tree of heaven honey contain the highest fructose content, while the lowest content was found in strawberry tree honey.The volatile compounds in the honey were isolated using headspace solid-phase microextraction (HS-SPME) with a gray fiber and analyzed using a coupled gas chromatography-mass spectrometry system. The volatile compounds with the highest content were: benzaldehyde, 2- furancarboxaldehyde (furfural), 2-phenylacetaldehyde, 4-methoxybenzaldehyde, linalool, trans-linalool oxide (furan type), lilac aldehyde isomers, nonanol, and 2,3,5-trimethylpyrazine. 5-hydroxymethylfurfural (HMF) was identified only in strawberry tree honey, while methyl syringate and methyl salicylate were identified only in savory honey