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Aromatic profile of olive oil : bachelor thesis
No full textMaslina (Olea europea L.) je jedna od najstarijih kultiviranih biljaka i jedna od najvažnijih kultura u jadranskom dijelu Hrvatske. Maslina se uzgaja uglavnom zbog proizvodnje maslinovog ulja. Jedinstvena i delikatna aroma maslinovog ulja pripisuje se hlapljivim spojevima koji se razvijaju tijekom i poslije ekstrakcije ulja iz ploda masline. Svrha ovog rada bilo je istražiti spojeve arome u maslinovom ulju proizvedenom za domaću upotrebu. Hlapljivi spojevi arome izolirani su dvjema metodama, vodenom destilacijom i mikroekstrakcijom vršnih para na krutoj fazi (HS-SPME). Dobiveni uzorci hlapljivih spojeva, destilat i vršne pare, analizirani su plinskom kromatografijom-spektrometrijom masa (GC-MS). Destilat maslinovog ulja karakterizira visoki udio nezasićene masne kiseline, oleinske kiseline, a slijede 5- (hidroksimetil)furfural (HMF) i alkohol glicerol. Oleinska kiselina i glicerol vjerojatno potječu od hidrolize triglicerida maslinovog ulja do koje je došlo tijekom vodene destilacije. Glavni sastojci vršnih para maslinovog ulja su C 6 hlapljivi spojevi, aldehid trans-heks-2-enal i alkohol trans-heks-2-en-1-ol koji spadaju u skupinu nositelja tzv. "zelenih mirisnih nota". Navedeni C 6 hlapljivi spojevi nisu identificirani u destilatu maslinovog ulja. HS-SPME metoda je bolja metoda za izolaciju spojeva arome maslinovog ulja.Olive (Olea europea) is one of the the oldest cultivated plant species, and one of the most important crops in the Adriatic part of Croatia. Olive is cultivated mainly for the production of the olive oil. The unique and delicate aroma of olive oil is attributed to the volatile compounds that develop during and after oil extraction from the olive fruit. The aim of this study was to investigate the aroma compounds in homemade olive oil. Volatile aroma compounds were isolated by two methods, hydrodistillation and headspace solid-phase microextraction (HS- SPME). The obtained samples, namely distillate and headspace, were analyzed by gas chromatography-mass spectrometry (GC/MS). The olive oil distillate was characterized by high concentration of unsaturated fatty acid, oleic acid, followed by 5-(hydroxymethyl)furfural (HMF) and alcohol glycerol. Oleic acid and glycerol probably derived from the hydrolysis of olive oil triglycerides. The main constituents of olive oil headspace are C 6 volatile compounds, namely aldehyde trans-hex-2-enal and alcohol trans-hex-2-en-1-ol, which belong to the so-called "green" aroma compounds. On the other hand, C 6 volatile compounds were not identified in olive oil distillate. So, headspace solid-phase microextraction is more suitable method for the investigation of olive oil aroma compounds
Developing HACCP system in cheese from bladdder production : bachelor thesis
No full text1. siječnja 2009. godine na snagu je stupila Odredba Zakona o hrani (NN 46/07) prema kojoj su svi subjekti u poslovanju s hranom, osim na razini primarne proizvodnje, dužni uspostaviti sustav upravljanja sigurnošću hrane koji se temelji na principima HACCP sustava. U skladu s time svi subjekti u poslovanju s hranom do tog datuma bili su dužni uspostaviti i implementirati u svoje proizvodne pogone HACCP sustav. HACCP sustav ima veliku ulogu u sprječavanju opasnosti ili snižavanju razine opasnosti na prihvatljivu razinu te kontroli kritičnih točaka. Svaka organizacija koja se bavi proizvodnjom i preradom hrane mora imati sustav kontrole kvalitete hrane. Svrha ovog rada je prikazati uspostavu sustava kontrole HACCP sustava u proizvodnom pogonu mljekare I-PAK d.o.o. u procesu proizvodnje sira iz mješine te opisati pojedine korake pri uvođenju HACCP sustava u proces proizvodnje. U radu su korišteni podaci i iskustva iz tvrtke I-PAK d.o.o. Također, opisani su svi rizici, pripadajuće kontrolne mjere, analiza rizika i utvrđivanje kritičnih kontrolnih točaka u procesu proizvodnje sira iz mješine u pogonu I-PAK d.o.o. Određivanje kritičnih kontrolnih točaka provedeno je pomoću analize opasnosti i uz pomoć stabla odluke. Navedena je sva dokumentacija i ostale radnje koja obuhvaća HACCP sustav.On January 1, 2009, The regulation of the Food Act (NN 46/07) was put into effect, under which all food business operators, except those at the primary production level, are required to establish a food safety management system based on the principles of the HACCP system. Accordingly, by this date, all food business operators were required to establish and implement in their manufacturing facilities a HACCP system. The HACCP system plays a major role in preventing hazards or reducing hazard levels to an acceptable level and controlling critical points. Every food production and processing organization must have a food quality control system. The purpose of this paper is to show the establishment of the HACCP control system in the production facility of the dairy I-PAK d.o.o. in the process of production of cheese from bladder and describe the individual steps in introducing the HACCP system into the production process. This paper uses data and experience from dairy I-PAK d.o.o. Also, all the risks, related control measures, risk analyzes and identification of critical control points are explained in the process of production of cheese from bladder from dairy I-PAK d.o.o. The determination of critical control points was performed using a hazard analysis and with the help of a decision tree. All documentation and other actions covered by the HACCP system are listed
Potenciometric testing of the influence of teflon share on the response of ion-selective membranes to phosphate ions : master thesis
No full textU ovom radu ispitivan je odziv ionsko–selektivnih membrana na fosfatne ione (PO 4 3- ), odnosno utječe li promjena udjela teflona u sastavu, kao neaktivnog nosača, na odziv samih membrana. Elektrokemijsko ponašanje je praćeno potenciometrijom zbog jednostavnosti, praktičnosti i pristupačnosti same metode te su sva mjerenja ponovljena minimalno tri puta pri pH = 13. Ionsko–selektivne membrane su ispitivane u elektrokemijskoj ćeliji uz otopinu dinatrijevog hidrogenfosfata, Na 2 HPO 4 , koja je pripremljena u otopini natrijeve lužine, pri pH = 13, metodom slijednog razrjeđivanja. Prilikom mjerenja je bilježena vrijednost elektrodnog potencijala te su se ista odvijala sve dok razlika između dvaju mjerenja nije iznosila 1 do 2 mV.The purpose of this thesis was to test the response of ion–selective membranes on phosphate ions, PO 4 3- , precisely does the change in the content of teflon, as an inactive carrier, effect the response. Electrochemical behaviour was carried out using potentiometry because of its simplicity, practicality and its affordability. All measurements were repeated three times in pH = 13. Ion–selective membranes were tested for in an electrochemical cell using di sodium hydrogen phosphate, Na 2 HPO 4 , which was prepared in sodium hydroxide buffer, NaOH using sequentially dilution method. For each measurement, the value of the electrode potential was recorded and were repeated until the potential difference reached about 1 or 2 mV between two consecutive measurements
Testing membrene system resopense FePO4:Ag2S:PTFE (1:1:2; 1:4:3,33) to phosphete ions : bachelor thesis
No full textIzrađene su ion-selektivne membrane sljedećeg sastava:
Membrana 1. FeP : Ag2S : PTFE = 1 : 1 : 2
Membrana 2. FeP : Ag2S : PTFE = 1 : 4 : 3,33
Metodom slijednog razrjeĎivanja ispitivan je odziv fosfatnih iona u otopini di-natrijevog hidrogen fosfata. Zbog jednostavnosti, praktičnosti i niske cijene potenciometrijska se metoda pokazala najučinkovitijom.Ion-selective membranes with the following content have been made:
Membrane 1. FeP : Ag2S : PTFE = 1 : 1 : 2
Membrane 2. FeP : Ag2S : PTFE = 1 : 4 : 3,33
Phosphate ions response in the solution of disodium hydrogen phosphate was tested using serial dilution method. Potentiometric method proved to be the most efficient considering its simplicity, effectiveness and low price
Volatile organic compounds of invasive red alga Asparagopsis taxiformis (Rhodophyta): halogenated hydrocarbons : diploma thesis
No full textAlge su široka skupina fotosintetskih autotrofnih organizama nalik na biljke, ali bez korijena, lišća ili cvjetova. Osim što su najveći proizvoĊaĉi kisika, pokazatelji su stanja okoliša, proĉišćivaĉi voda, ali i predmet razliĉitih istraživanja. Pokazuju širok spektar bioaktivnosti (kao što su anti-age, antimikrobna, protuupalna i antidijabetiĉna aktivnost). S obzirom da alge žive u ekstremnim uvjetima, morale su razvijati mehanizme obrane, a organohalogeni spojevi u morskim algama imaju važnu ulogu u preživljavanju. Crvena boja tih algi dolazi od pigmenta fikoeritrina koji im omogućuje fotosintezu u tami. Crvene alge sadrže terpene s citotoksiĉnim djelovanjem, a strukturna raznolikost halogeniranih monoterpena je važan faktor inteziteta razliĉitih bioaktivnosti. U analiziranoj algi Asparagopsis taxiformis glavni halogenirani ugljikovodici bili su tribrommetan i dibromjodmetan. U radu su se za ekstrakciju vršnih para uzorka koristile dvije metode: a) mikroekstrakcija vršnih para na ĉvrstoj fazi (HS-SPME) gdje je zastupljenost tribrommetana bila 53,57%, odnosno 69,79%, a dibromjodmetana 11,78%, odnosno 14.22% i b) izravna statiĉka analiza vršnih para (HS) koristeći automatski sustav s postotkom tribrommetana 64,46% i dibromjodmetana 15,30%. Korištena je i hidrodestilacija u modificiranoj Clevenger aparaturi, a u isparljivom ulju zastupljenost glavnog spoja tribrommetana bila je 76,58% uz dibromjodmetan 13,39%. Organska analiza izoliranih isparljivih spojeva provedena je vezanim sustavom plinske kromatografije i spektrometrije masa (eng. gas chromatography amd mass spectrometry, GC-MS).Algae are a broad group of photosynthetic autotrophic organisms resembling plants, but without roots, leaves or flowers. In addition to being the largest producer of oxygen, they are the indicators of the state of the environment, water purifiers, but also the subject of various research. They exhibit a wide range of bioactivities such as anti-age, antimicrobial, anti-inflammatory and antidiabetic. Since algae live in extreme conditions, defense mechanisms have to be developed, and organohalogen compounds in marine algae play an important role in survival. The red color of these algae originates from the pigment ficoeritrine, which enables photosynthesis in the dark. Red algae are the main source of terpenes with cytotoxic activity, and the structural diversity of halogenated monoterpenes is an important factor for the bioactivity intensity. In the analyzed alga Asparagopsis taxiformis the main halogenated hydrocarbons were tribromomethane and dibromoiodomethane. In this work, two methods were used for the extraction of headspace compounds: a) headspace solid-phase microextraction (HS-SPME) with the abundance of tribromomethane 53.57%, rescpetivly 69.79% and dibromoiodomethane with 11.78%, respectivly 14.22% and direct headspace static analysis (HS) using an automatic system with the percentages of tribromomethane 64.46% and dibromoiodomethane 15.30%. Hydrodistillation was also used in the modified Clevenger apparatus and the volatile oil contained the main compound tribromomethane (76.58%) along with dibromoiodomethane (13.39%). The organic analysis was carried out by a gas chromatography and mass spectrometry (GC-MS
Monitoring of soil pollution using The Environmental information system : bachelor thesis
No full textTlo je prirodna tvorevina sastavljena od mineralnih sirovina, čestica, organske tvari, vode, zraka i živih organizama. Povezuje vodu, zrak i zemlju te ima nezamjenjivu ulogu u ekosustavu. U ovom radu analizirano je stanje onečišćenosti tla na području Splitsko-dalmatinske županije u razdoblju 2013.- 2017. primjenom Informacijskog sustava stanja okoliša. Provedena je analiza eksploatacijskih i istražnih polja, crnih točaka te količine prijavljenog proizvodnog otpada. Rezultati pokazuju da na području županije prevladavaju eksploatacijska i istražna polja mineralnih sirovina A-G kamena, T-G kamena, gipsa, tufa i boksita. Ukupno šest crnih točaka je locirano na području županije (Salonit-Mravinačka kava, Salonit- igralište Omladinac, Salonit-krug tvornice, Salbunara, Kaštelanski zaljev-Jugovinil, Salonit-Kosica). Analiza prijavljenog proizvodnog otpada ukazuje da je najzastupljeniji otpad iz grupe 19 00 00 (otpad iz uređaja za postupanje s otpadom, uređaja za pročišćavanje gradskih otpadnih voda i pripremu pitke vode i vode za industrijsku uporabu), uz najveću tendenciju rasta zabilježenu u 2017. godini.Soil is a natural formation composed of minerals, particles, organic matter, water, air and living organisms. It connects water, air and earth and has an irreplaceable role in the ecosystem. In this paper, the analysis of soil pollution in the Split-Dalmatia County during the period 2013 - 2017 by application of the Environmental Information System has been performed. The exploitation and exploration fields, black spots and the amount of production waste have been analysed. The results show that exploitation and exploration fields of mineral resources AG stone, TG stone, gypsum, tuff and bauxite are dominated. Total of six black spots are located in the county (Salonit-Mravinačka kava, Salonit-playground Omladinac, Salonit-factory circle, Salbunara, Kaštela Bay-Jugovinil, Salonit-Kosica). The analysis of the production waste shows that waste from the group 19 00 00 is dominated (waste from treatment devices, from wastewater treatment plants and plants for preparation of drinking water and water for industrial use), with a highest growth trend in 2017
Polyelectrolytes assembly for electrochemical sensing application by layer-by-layer method : bachelor thesis
No full textRazvoj osjetilnih premaza, važnih elemenata senzora koji ujedinjuju funkcionalnost, jednostavnost, kemijsku i fizičku stabilnost, ima veliku uloga u napretku elektrokemijskih senzorskih sustava. Zbog svoje raznolikosti i jednostavnosti korištenja, polielektroliti su vrlo čest odabir u izradi elektrokemijskih osjetilnih slojeva. Polielektroliti se u strukturama elektrokemijskih senzora najčešće koriste za zarobljavanje (ugradnja, imobilizacija) raznih materijala u osjetilne slojeve. Ti materijali često mogu povećati osjetljivost, selektivnost te mogu služiti kao medijatori prijenosa elektrona između analita i pretvornika. Analitička izvedba se može značajno poboljšati sinergističkim učinkom materijala (osjetilni materijal, pretvornik, medijator) prisutnih u senzorskim strukturama. Strukture navedenih senzora se mogu postići primjenom raznih metoda (nakapavanje, umakanje), a jedna od najčešće korištenih metoda je metoda ''sloj na sloj''. Ovaj rad prikazuje primjenu navedene metode u razvoju raznih višeslojnih filmova i ulogu polielektrolita u tim strukturama.The development of sensing coatings, as important sensor elements that integrate functionality, simplicity, chemical stability, and physical stability, has been shown to play a major role in electrochemical sensing system development trends. Because of its versatility amd scalability, polyelectrolytes are often used in development of electrochemical sensing layers. Polyelectrolytes are mainly used in electrochemical sensor architectures for entrapping (incorporation, immobilization, etc.) various materials into sensing layers. These materials can often increase sensitivity, selectivity and be used as mediators of electron transfer between an analyte and transducer. Analytical performance can be significantly improved by the synergistic effect of materials (sensing material, transducer, and mediator) present in these structures. Structures of said sensors can be achieved using different methods (drop-casting, dip-coating), and one of the most commonly used method is the layer-by-layer method. This work presents the application of this method in the development of various multilayer films and the role of polyelectrolytes in these structures
Extraction of uranium(VI) and plutonium(IV) from a nuclear waste : bachelor thesis
No full textEkstrakcija uranija i plutonija se izvodi primjenom PUREX procesa (engl. Plutonium Uranium Reduction Extraction). U radu su objašnjene današnje metode i varijacije PUREX procesa koje su najviše zastupljene. UtvrĎene su značajke PUREX procesa i optimalni načini provoĎenja istog, te istaknuta važnost oporabe otpadnog nuklearnog goriva. Plutonij(IV) i uranij(VI) tvore stabilne komplekse s nitratima i organskim ekstraktantom tri-n-butil fosfatom (TBP), a što omogućuje njihovo odvajanje od fisijskih produkata. Nastali neutralni kompleksi plutonija(IV) i uranija(VI) s nitratima i TBP-om se koekstrahiraju u organsku fazu (npr. kerozin) dok kationi fisijskih produkata uglavnom ne tvore komplekse s TBP-om i ne ekstrahiraju se. Nakon uklanjanja fisijskih produkata, plutonij(IV) i uranij(VI) se meĎusobno odvajaju na temelju selektivnog reduciranja Pu(IV) do Pu(III) koji se ne ekstrahira u opisanim uvjetima, te se zadržava u vodenoj fazi. Uranij(VI) se ne reducira i ekstrahira se u organsku fazu. Razdvojeni uranij(VI) i plutonij(IV) se dodatno pročišćavaju. Kljuĉne rijeĉi: ekstrakcija, uranij(VI), plutonij(IV), oporaba nuklearnog otpadaExtraction of uranium and plutonium is performed by the PUREX process (Plutonium Uranium Reduction Extraction). The thesis explains contemporary methods and variations of the PUREX process that have been studied and most commonly used. The characteristics of the PUREX process and the optimal ways of its implementation have been determined, and the importance of recovering a nuclear waste fuel has been emphasized. Plutonium(IV) and uranium(VI) form stable nitrate complexes with the organic extractant tri-n- butyl phosphate (TBP) that allows their separation from the fission products. The neutral plutonium(IV) and uranium(VI) complexes formed with nitrates and TBP are then coextracted into an organic phase (e. g. kerosene), while the cations of fission products generally do not form TBP complexes and do not extract. After a removal of the fission products, plutonium(IV) and uranium(VI) are separated from each other based on a selective reduction of Pu(IV) to Pu(III). Plutonium(III) does not extract and remains in the aqueous phase, while uranium(VI) is not reduced and is extracted into the organic phase under described conditions. The separated uranium(VI) and plutonium(IV) are additionally purified
Monitoring of leaching of the olive pomace leachate : bachelor thesis
No full textU ovom radu ispitani su uzorci komine masline iz dviju uljara Splitsko-dalmatinske županije s različitim procesima proizvodnje. U uzorcima je određen sadržaj vode koji je iznosio 51,2% za uzorak 3- faznog procesa i 67,9% za uzorak iz 2-fazne proizvodnje, a sadržaj organske tvari iznosio je 97,95% za prvi, odnosno 95,47% za drugi uzorak. Ispiranjem uzorka komine masline iz 3-faznog procesa destiliranom vodom tijekom tri dana, dobivena je procjedna voda za svaki dan ispiranja u kojoj je određena pH vrijednost, mutnoća, KPK i BPK 5 te dušik po Kjeldahlu. Nakon prvog dana ispiranja, uzorak procjedne vode komine masline imao je najveće organsko opterećenje koje se očitovalo u KPK vrijednosti od 4736,2 mg O 2 /L i BPK 5 od 2650,0 mg O 2 /L te mutnoći od 188,0 NTU, pH 4,97 i sadržaju dušika u iznosu od 22,4 mg N/L. Obzirom na dobivene vrijednosti parametara, prema Pravilniku o graničnim vrijednostima emisija otpadnih voda, ispitivana procjedna voda ne bi se smjela ispustiti u površinske vode niti u sustav javne odvodnje bez prethodne obrade. Drugi i treći dan ispiranja komine dao je uzorke sa znatno nižim vrijednostima pokazatelja što ukazuje na opasnost od procjeđivanja otpadnih voda ukoliko se komina ostavi na otvorenom prostoru.Two olive mill pomace samples from two Split-Dalmatia county’s olive mills with different types of production were characterized. Water content for 3-phased process sample is determined to be 51.2% and 67.9% for 2-phased process sample. Organic matter content has been determined to be 97.95% for the first sample and 95.47% for the second one. By leaching the 3-phased process olive pomace sample with distilled water, three samples of olive pomace leachate were obtained, one for each day of leaching. COD and BOD 5 values of three leachate samples were determined, as well as pH value, turbidity and Kjeldahl nitrogen content. After the first day of leaching, the sample showed the highest organic matter content with extremely high COD value of 4736.2 mg O 2 /L and BOD 5 value of 2650.0 mg O 2 /L, along with turbidity of 188.0 NTU, pH value of 4.97 and Kjeldahl nitrogen content of 22.4 mg N/L. Considering the given parameters, wastewater must not be released in natural waters nor the sewage system, according to the Croatian Policy of limiting values of wastewater emissions. Second and third day of leaching produced wastewater samples with significantly lower parameters which confirm leaching of the olive pomace as a harmful process in case of exposing of the pomace on unprotected open area
Cannabis and cannabis products : bachelor thesis
No full textKonoplja je jedna od najkontroverznijih biljaka današnjice i njezina medicinska primjena je podijelila današnju znanstvenu zajednicu. Proizvodi od konoplje koriste se u prehrani ljudi, ţivotinja i u kozmetici, te imaju izrazitu nutritivnu vrijednost koja obiluje zdravim masnoćama, proteinima i brojnim mineralima. Konoplja se pokazala dobrom u lijeĉenju mnogih bolesti kao i u preventivi mnoštva oboljenja. U proizvode za ljudsku prehranu spadaju brašno od konoplje, ĉaj, protein, ulje, te sjemenke konoplje. Konoplja ima i vrlo vaţnu ulogu u ekološkoj poljoprivredi jer uvelike pridonosi oĉuvanju okoliša i to ne samo u smislu ĉišćenja oneĉišćenog tla već i u smanjenju emisije CO 2 .Cannabis is one of the most controversial plants today and its medical application has divided today’s scientific community. Cannabis products are used in human and animal diets and for cosmetic purposes rich in healthy fats, proteins and many minerals. Cannabis has been proven to be good in treating many diseases as well in preventing a multitude of diseases. Human food products include hemp flour, tea, protein, oil, and hemp seeds. Cannabis also has a very important role in organic agriculture because it greatly contributes to the preservation of the soil, not only in terms of cleaning contaminated soil but also in reducing CO 2 emissions