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Ecological production and steps to the ecolabel for olive oil : bachelor thesis
No full text: Ekološka poljoprivreda podrazumijeva specifični sustav održivoga gospodarenja u poljoprivredi s ciljem proizvodnje zdrave hrane, odnosno zadovoljavanja odgovarajućih društvenih i gospodarskih potreba za očuvanje prirodnog ekosustava i okoliša. Konvencionalna poljoprivreda je, nakon prometa, drugi najveći uzročnik zagađenja tla, vode i zraka u Hrvatskoj. Europska unija zakonski je regulirala ekološku poljoprivredu Uredbom EU br. 2092/91. U Hrvatskoj je zakonski regulirana tek 2001. godine Zakonom o ekološkoj proizvodnji poljoprivrednih i prehrambenih proizvoda te 2010. godine novim Zakonom o ekološkoj proizvodnji i označavanju ekoloških proizvoda (NN br. 139/10). Razvoj ekološkog maslinarstva direktno je povezan s razvojem ekološke poljoprivrede. Prvi podaci EUROSTAT-a o količinama ekološki proizvedenih maslina prikupljeni su već 2002. godine za Italiju, dok se od 2009. godine prati i Hrvatska. Proizvođači koji se odluče na ekološku proizvodnju, a isto tako i na ekološku proizvodnju maslinovog ulja, moraju slijediti zakonsku regulativu koja je obavezna u ovom području, a na temelju dokaza implementacije zakonskih koraka mogu proizvod deklarirati kao ekološki. U sklopu završnog rada provedeno je istraživanje putem ankete pod nazivom 'Percepcija potrošača o eko proizvodima i eko maslinovom ulju' kako bi se dao uvid koliko smo upoznati sa samim pojmom ekološkog proizvoda te kakav je stav ispitanika o ekološki proizvedenom maslinovom ulju.Organic agriculture implies a specific system of sustainable management in agriculture with the aim of producing healthy food, hence meeting the appropriate social and economic needs for the preservation of the natural ecosystem and the environment. Conventional agriculture is, after traffic, the second largest soil, water and air polluter in Croatia. Since 90% of food comes from soil, conventional agriculture in the last few decades consequently caused the reduction of hummus for 50%. The European Union legally regulated organic farming with Council Regulation (EEC) No 2092/91 of June 1991. In Croatia it was legally regulated only in 2001 by Law on organic agriculture and food products (NN no. 12/01), and again in 2010 by adoption of the new Law (NN no. 139/10). The development of organic olive growing are directly related to the development of organic agriculture. The first data from EUROSTAT on the quantities of organically produced olives was already collect in 2002. for Italy, while Croatia is being monitored since 2009. Manufacturers who opt for organic production, as well as organic production of olive oil, must follow the mandatory law legislation in this area and based on evidence of the implantation of legal steps they can declare the product as ecological. As a part of the final work, a survey entitled ‘Consumer perception of organic products and organic olive oil’ was conducted to provide insight into how familiar we are with the term organic product and what is the attitude of respondents about organically produced olive oil
Inhibitory effect selected plant extracts on α-glucosidase activity : diploma thesis
No full textŠećerna bolest je rastući javnozdravstveni problem. Mnoga provedena istraživanja potvrdila su dobrobiti ljekovitih biljaka s hipoglikemijskim učinkom u liječenju dijabetesa. Učinak ovih biljaka može odgoditi razvoj komplikacija šećerne bolesti te ispraviti metaboličke nepravilnosti. Cilj ovog rada bio je testirati sposobnost eteričnih ulja i hidrolata odabranih biljnih vrsta da inhibiraju enzim α-glukozidazu, metodom po Sigma-Aldrichu. Za uzorke hidrolata je određen i sadržaj ukupnih fenola metodom po Folin- Ciocalteu. Rezultati su pokazali da je najučinkovitiji inhibitor među testiranim uzorcima hidrolat biljke Juniperus communis spp. nana (IC 50 =47,89 mg/L). Ostali uzorci biljaka za sve testirane koncentracije slabo inhibiraju enzim α-glukozidazu. Među eteričnim uljima najbolji inhibitor enzima α-glukozidaze je ulje biljke Hymenocarpos circinnatus koje u koncentraciji 1 g/L inhibira enzim s 52,16±3,82 %. Nešto lošiji učinak kod iste koncentracije imaju Centaurea scabiosa s 38,72±11,05 % i Mantisalca salmantica 32,2±12,72 %, dok eterično ulje biljke Campanula rapunculus nije pokazalo inhibicijski učinak na ispitivani enzim. Najučinkovitiji inhibitor, hidrolat biljke Juniperus communis spp. nana sadrži i najviše fenolnih spojeva (196 mg GAE/g hidrolata), dok za ostale testirane hidrolate nema značajne povezanosti između sadržaja ukupnih fenola i inhibicije enzima.Diabetes is a growing public health problem. Many studies have confirmed the benefits of medicinal plants with a hypoglycemic effect in the treatment of diabetes. The effect of these herbs can delay the development of diabetes complications and correct metabolic abnormalities. The aim of this study was to test the ability of essential oils and hydrolats of selected plant species to inhibit the α-glucosidase enzyme, using the Sigma-Aldrich method. The content of total phenolics was determined by the Folin-Ciocalteu method for the hydrolate samples. The results showed that the most effective inhibitor among the tested hydrolats was that of the Juniperus communis spp. nana plant (IC 50 =47.89 mg/L). Other samples at all tested concentrations weakly inhibit the enzyme. Among essential oils, the best inhibitor of α-glucosidase enzyme is the oil of the plant Hymenocarpos circinnatus, which at a concentration of 1 g/L inhibits the enzyme by 52.16 ± 3.82 %. Centaurea scabiosa with 38.72±11.05 % and Mantisalca salmantica with 32.2±12.72 % had a slightly lower inhibitory effect at the same concentration, while the essential oil of Campanula rapunculus showed no inhibitory effect on this enzyme. The highest total phenolics content was found in most effective inhibitor; hydrolate of the plant Juniperus communis spp. nana (196 mg GAE/g hydrolate), while for the other tested hydrolats there is no significant correlation between total phenolics content and enzyme inhibition
Volatile compounds of sage honey : diploma thesis
No full textHlapljivi spojevi prisutni u medu su pretežito botaničkog podrijetla i često nisu stabilni te se mogu transformirati tijekom sazrijevanja meda, njegova skladištenja i zagrijavanja. U ovom radu su istraživani hlapljivi spojevi meda od kadulje. Hlapljivi spojevi izolirani su hidrodestilacijom u modificiranoj aparaturi po Clevengeru. Pored toga, provedena je i mikroekstrakcija vršnih para na krutoj fazi (HS- SPME) iz vode uzete iz središnjeg dijela modificirane aparature po Clevengeru kao i iz tikvice za destilaciju. Uzorci hlapljivih spojeva su analizirani vezanim sustavom plinska kromatografija-masena spektrometrija (GC-MS). Kao dominantni spojevi identificirani su: 2-fenilacetaldehid, eikosan, trikosan i 2-furankarboksaldehid.The volatile compounds present in honey are predominantly of botanical origin and are often not stable and can be transformed during honey maturation, storage and heating. In this paper, volatile compounds of sage honey were investigated. The volatile compounds were isolated by hydrodistillation in a Clevenger modified apparatus. In addition, headspace-solid phase microextraction (HS-SPME) was performed from water taken from the central part of the Clevenger modified apparatus as well as from a distillation flask. Samples of volatile compounds were analyzed by analytical method gas chromatography-mass spectrometry (GC-MS). The dominant compounds were identified as: 2- phenylacetaldehyde, eicosan, tricosan and 2-furancarboxaldehyde
Study of the response of the membrane based on FePO4 Ag2S : PTFE = 1 : 1 : 2 with nanoparticles of zinc oxide and aluminium oxyhydroxide at pH = 1 and pH = 1.5 : bachelor thesis
No full textGlavni cilj ovoga završnog rada je testiranje odziva membrana za ion-selektivne elektrode na Fe 3+ katione u otopini željezova(Ⅲ) nitrata pri pH=1 i pH=1,5 kao i utvrđivanje mogućnosti njihove praktične primjene. Testiranje odziva membrana izrađenih od mješavine željezova fosfata, srebrova sulfida i politetrafluoroetilena u omjeru 1 : 1 : 2 uz dodatak nanočestica cinkovog oksida i aluminijevog okshidroksida izvršeno je potenciometrijskom metodom upravo zbog ekonomičnosti postupka te jednostavnosti izvedbe. Odziv na željezove(Ⅲ) katione ispitan je kod 6 različitih membrana pri pH=1 te pH=1,5:
• Membrana PNA4, PNA5 i PNA6 sastava FePO 4 : Ag 2 S : PTFE = 1 : 1 : 2 sa 0,25%, 0,5% i 1% nanočestica aluminijeva okshidroksida
• Membrana PNZ1, PNZ2, PNZ3 sastava FePO 4 : Ag 2 S : PTFE = 1 : 1 : 2 sa 0,5%, 1% i 1,5% nanočestica cinkova oksida Ispitan je odziv na Fe 3+ katione u otopini željezova(Ⅲ) nitrata metodom slijednog razrijeđenja uz pufer nitratnu kiselinu-HNO3 (pH=1 i pH=1,5). Mjerenja su uglavnom ponavljana 3 puta uz bilježenje promjene potencijala te vremena odziva. Rezultati testiranja odziva na poslijetku su prikazani grafički.The main goal of this bachelor tesis is to test the response of membranes for ion-selective-electrodes to Fe3+ cations in a solution of iron(Ⅲ) nitrate at pH=1 and pH=1,5, as well as to determine the possibility of their practical use. Testing the response of membranes made of a mixture of iron phosphate, silver sulfide and Teflon in a ratio of 1: 1: 2. was performed by the potentiometric method precisely because of the economic procedure and simplicity of performance. The response to iron(III) cations is tested for 6 different membranes at pH=1 and pH=1,5:
• Membranes PNA4, PNA5 and PNA6 composition FePO 4 : Ag 2 S : PTFE = 1 : 1 : 2 with 0,25%, 0,5% and 1% nanoparticles of aluminium oxyhydroxide
• Membrane PNZ1,PNZ2 and PNZ3 composition FePO 4 : Ag 2 S : PTFE = 1 : 1 : 2 with 0,5% , 1% and 1,5 % nanoparticles of zinc oxide The response to Fe 3+ cations was tested in a solution of iron(Ⅲ) nitrate by sequential dilution with nitric acid pufer-HNO 3 (pH=1 and pH=1,5).
Measurements are generally repeated 3 times, writing down the changes in potential and response time. The test results of the responses in the end were shown graphically
Influence of impeller type on characteristics of gas dispersion in liquid : diploma thesis
No full text: Disperzija ili raspršenje plina u kapljevini se primjenjuje u nizu industrijskih procesa u kojima je potrebno ostvariti prijenos tvari između tih dviju faza, a često se provodi u miješalicama s mehaničkim miješanjem. Upravo o geometrijskim karakteristikama miješalice, prije svega o tipu miješala, ovisit će hidrodinamički uvjeti u sustavu, a koji se direktno odražavaju na intenzitet prijenosa tvari iz plinovite u kapljevitu fazu (ili obrnuto). Glavni zadatak ovog rada bio je ispitati utjecaj tipa miješala na karakteristike procesa raspršenja plina u kapljevini. Ispitivanje se provodilo u posudi za raspršenje plina volumena 10,85 dm 3 . Korištena su dva turbinska miješala, miješalo s diskom i ravnim lopaticama te miješalo s diskom i konkavnim lopaticama. U prvom dijelu eksperimentalnog rada određene su brzine vrtnje miješala pri kojima se postiže režim potapanja miješala, režim opterećenja sustava te režim potpunog raspršenja plina u kapljevini. Na temelju dobivenih vrijednosti tih brzina određene su eksperimentalne vrijednosti Froudeove i aeracijske značajke. Iste su uspoređene s teorijskim vrijednostima. U drugom dijelu rada određen je relativni utrošak snage miješanja za različite brzine vrtnje miješala koji predstavlja jedan od najbitnijih parametara u procjeni ekonomske isplativosti procesa. Naposljetku je na temelju mjerenja koncentracije otopljenog kisika u vodi određen volumni koeficijent brzine prijenosa kisika, k L a, a potom i brzina prolaza kisika iz zraka u vodu. Usporedbom dvaju korištenih tipova miješala utvrđeno je da se veće vrijednosti brzine prijenosa kisika postižu korištenjem miješala s diskom i ravnim lopaticama, no uz nešto veći utrošak snage. S obzirom na navedeno, isto se može smatrati prikladnijom opcijom u koliko je primaran cilj operacije ostvarenje većih brzina prolaza kisika u sustavu.Gas dispersion in liquid is applied in a range of industrial processes in which mass transfer between these two phases is required. It is often carried out in mechanically agitated vessels. It is the geometrical characteristics of the vessel, primarily the type of mixer, that will determine the hydrodynamic conditions in the system, which directly affect the intensity of the mass transfer from the gaseous to the liquid phase (or vice versa). The main task of this research was to examine the influence of impeller types on the characteristics of gas dispersion in liquid. Experiments were conducted in a mixing vessel of 10,85 dm 3 volume. Two types of impellers were used: a concave-blade turbine with disk and a flat-blade turbine with disk. Firstly, agitator speeds at which different flow regimes are achieved were determined. The Froude and the aeration numbers at those flow regimes were calculated. Experimental aeration numbers were compared with theoretical values. Secondly, the relative power demand for different agitator speed was determined. This parameter is one of the most important parameters for assessing the economic viability of the process. Finally, based on the measurement of the concentration of dissolved oxygen in liquid, volumetric oxygen transfer coefficient, k L a, and the oxygen transfer rate from air into water were determined. By comparing the two types of impellers used, it was found that higher values of oxygen transfer rate are achieved by using the flat-blade turbine with disk, but with a higher power demand. Considering the stated, this impeller can be considered a more appropriate option if the primary goal of the operation is to achieve higher oxygen flow rates in the system
Analysis of the influence of electrode distance and electrolyte addition on the efficiency of treatment of leachate from composting processes using integrated electrocoagulation process and treatment on natural zeolite : diploma thesis
No full textU procesu kompostiranja osim komposta nastaju i znatne količine procjedne otpadne vode opterećene organskim i anorganskim štetnim tvarima te mikroorganizmima. Upravo iz ovih razloga postoji potreba za pročišćavanjem otpadnih procjednih voda iz procesa kompostiranja prije njihovog ispuštanja u prirodni recipijent. U ovom radu provedena su ispitivanja učinka procesa elektrokoagulacije pri različitim udaljenostima elektroda, s i bez dodatka zeolita i elektrolita na efikasnost pročišćavanja simulirane procjedne vode iz procesa kompostiranja. Tijekom eksperimenta pratila se promjena pH vrijednosti, temperature i električne vodljivosti. Na početku i kraju eksperimenta određivani su: pH vrijednost, električna vodljivost, temperatura, mutnoća, ukupni isparni ostatak, kemijska potrošnja kisika (KPK), dušik po Kjeldahlu te brzina taloženja suspenzije. Rezultati pokazuju da udaljenost elektroda, dodatak elektrolita i zeolita značajno utječu na pokazatelje kvalitete, brzinu taloženja, potrošnju elektroda i masu nastalog taloga. Provedena je analiza operativnih troškova procesa koristeći prikupljene podatke o utrošku masa elektroda za proces elektrokoagulacije s i bez dodatka zeolita.During composting process, in addition to compost production, a large amounts of leachate, containing high concentrations of organic and inorganic harmful substances and microorganisms, are also generated. For that reason there is a need to treat leachate from the composting process before releasing it into the natural recipient. In this paper, analysis of efficiency of the electrocoagulation process at different distances of electrodes, with and without the addition of zeolite and electrolite, on simulated leachate from the composting process has been carried out. During the experiment, a change in pH, temperature and electrical conductivity was monitored. At the beginning and end of the experiment: pH value, electrical conductivity, temperature, turbidity, chemical oxygen demand (COD), total Kjeldahl nitrogen (TKN) and settling test of suspension were determined. The results show that the distance of electrodes, the addition od electrolytes and zeolites significantly affect quality indicators, settling rate, electrode consumption and precipitate mass. An analysis of the operational costs of the process was carried out using the collected data on the consumption of electrode masses for the electrocoagulation process with and without the addition of zeolites
Analysis of the influence of stirring speed, addition of zeolite and electrolyte on the efficiency of treatment of leachate from composting of biowaste using the integrated electrocoagulation process and treatment on natural zeolite : diploma thesis
No full textProcesom kompostiranja nastaje kompost kao korisni proizvod te procjedna otpadna voda opterećena organskim onečišćenjima i teškim metalima. Upravo zbog toga postoji potreba za njenom obradom. Uzorak simulirane procjedne vode iz kompostiranja biootpada obrađen je integriranim procesom elektrokoagulacije s i bez dodatka zeolita i elektrolita. Ispitivan je utjecaj različite brzine vrtnje miješala (70, 200 i 400 rpm) na učinkovitost procesa preko parametara: pH vrijednost, električna vodljivost, kemijska potrošnja kisika, dušik po Kjeldahlu, temperatura, mutnoća i ukupni isparni ostatak. Uz navedene pokazatelje praćena je i brzina taloženja. Prikupljeni su podaci za utrošak masa elektroda za vrijeme procesa iz čega su određeni operativni troškovi procesa. Rezultati pokazuju da brzina vrtnje miješala, dodatak zeolita i elektrolita mogu utjecati na efikasnost uklanjanja kemijske potrošnje kisika i dušika po Kjeldahlu. Vidljiv je porast temperature i pH dok električna vodljivost prikazuje blagi trend pada. Uklanjanje mutnoće je vrlo visoko, neovisno o promjeni parametara. Vrijednosti ukupnog isparnog ostatka su manje dodatkom zeolita jer on na sebe veže onečišćenja, ali je brzina taloženja bolja uz dodatak elektrolita i zeolita uz manje brzine vrtnje miješala.The composting process produces compost as a useful product and leachate loaded with organic pollutants and heavy metals. That is why there is a need for its processing. Simulated leachate from composting of biowaste was processed by an integrated electrocoagulation process with and without the addition of zeolite and electrolyte. The influence of different stirring speed (70, 200 and 400 rpm) on the process efficiency was investigated over parameters: pH value, electrical conductivity, chemical oxygen demand, total Kjeldahl nitrogen, temperature, turbidity and total solids. In addition to the above indicators, the setteling test was also performed. Data for the consumption of electrode masses during the process were collected from which the operational costs of the process were determined. The results show that the stirring speed, the addition of zeolite and electrolyte can affect the efficiency of removal of chemical consumption of oxygen and nitrogen according to Kjeldahl. An increase in temperature and pH is visible while the electrical conductivity shows a slight downward trend. Turbidity removal is very high, independent of parameter changes. The values of the total solids are less with the addition of zeolite because it binds contaminants, but the setteling test is better with the addition of electrolyte and zeolite with lower stirring speed
Characterization of aromatic compounds of brandy biska : diploma thesis
No full textBiska je tradicionalna istarska rakija koja se proizvodi aromatiziranjem rakije lozovače ili komovice prirodnim ekstraktom žute imele (Loranthus europaeus) ili bijele imele (Viscum album). Tijekom njene proizvodnje nastaju brojne aromatične hlapljive tvari čiji udjel i sastav određuje kvalitetu gotovog proizvoda. Cilj ovog rada je utvrditi i usporediti profil hlapljivih sastojaka 6 uzoraka rakije biske. Hlapljivi spojevi izolirani su korištenjem dvije tehnike izolacije: mikroekstrakcija vršnih para na krutoj fazi (engl. headspace-solid phase microextraction, HS-SPME) i ekstrakcija tekuće-tekuće. Analiza izoliranih spojeva provedena je primjenom spregnute tehnike plinska kromatografija – spektrometrija masa (engl. gas chromatography – mass spectrometry, GC-MS). Identificirano je ukupno 46 hlapljivih spojeva koji pripadaju sljedećim kemijskim skupinama: alkoholi, esteri, masne kiseline, aldehidi, alkani i terpeni. Najzastupljenije komponente su viši alkoholi 3-metil-butan-1-ol i 2-metil-propan-1-ol te etilni esteri srednjelančanih masnih kiselina etil-dekanoat i etil-oktanoat. Uočene su značajne razlike u aromatičnom profilu ovisno o korištenoj metodi izolacije, a samo je 8 istih spojeva identificirano korištenjem obje metode.Biska is a traditional Istrian brandy produced by flavoring lozovača brandy or komovica brandy with a natural extract of yellow mistletoe (Loranthus europaeus) or white mistletoe (Viscum album). During the production of Biska brandy, many aromatic volatile substances are generated, and their content and composition determine the quality of the finished product. The aim of this paper is to determine and compare the volatile componentsʼ profile of 6 samples of Biska brandy. Volatile compounds are isolated using two isolation metods: headspace-solid phase microextraction (HS-SPME) and liquid-liquid extraction. The analysis of isolated compounds was performed using gas chromatography– mass spectrometry (GC-MS). A total of 46 volatile compounds belonging to the following chemical groups have been identified: alcohols, esters, fatty acids, aldehydes, alkanes and terpenes. The prevailing amount of higher alcohols 3-methyl-butan-1-ol and 2-methyl-propan-1-ol as well as the ethyl esters of medium- chain fatty acids ethyl-decanoate and ethyl-octanoate were found. Significant differences in aromatic profile were detected depending on the isolation method used, and only 8 of the same compounds were identified using both methods
Developing HACCP system in prosciutto production : bachelor thesis
No full textU ovom radu prikazana je provedba HACCP sustava kod proizvodnje pršuta. Na samom poĉetku opisani su opći propisi i smjernice HACCP sustava kvalitete. Zatim su saţeto i jasno definirani i opisani svi koraci tehnološkog procesa proizvodnje pršuta, konstruirani dijagrami, te je opisan proizvod. Slijedila je analiza rizika svih koraka tehnološkog procesa, identificirane su CCP ocjenjivanjem rizika i primjenom dijagrama odluka. Za identificirane CCP izraĊen je HACCP plan za kontrolu i provoĊenje osiguranja kvalitete finalnog proizvoda.HACCP system implementation in technological process of prosciutto is described in this paper. In the begining of this paper legal acts and general guidelines of HACCP system are described. Afterwards, all steps of technological procceses of prosciutto are defined and described. Diagrams are shown and products are described. Risk analysis is done for every step of technological process, CCP are identified by risk evaluation and application of decision diagrams. These risks represented the basic of HACCP plan for control and ensuring the quality final products
Implementation of the food safety system in the production of smoked pig knees : bachelor thesis
No full textCilj ovog rada je opisati uspostavu sigurnosti hrane i implementacija HACCP sustava u proizvodnom pogonu za proizvodnju sušene kraĉice. Svrha rada bila je analiza opasnosti i odreĊivanje kritiĉnih kontrolnih toĉaka (KKT). OdreĊivanje kritiĉnih kontrolnih toĉaka provedeno je pomoću analize opasnosti i primjenom stabla odluke. IzraĊen je HACCP plan za proces proizvodnje koji ukljuĉuje naĉin monitoringa kritiĉnih kontrolnih toĉaka s utvrĊenim kritiĉnim granicama te važnost preduvjetnih programa i kontrole kvalitete.The aim of this bachelor thesis is to describe the establishment of food safety and the implementation of the HACCP system for the production of smoked pig knees. The purpose of the work was hazard analysis and determination of critical control points (CCP). The determination of critical control points was carried out using hazard analysis and the application of a decision tree. A HACCP plan for the production process has been developed, which includes the method of monitoring critical control points with established critical limits and the importance of prerequisite programs and quality control