As a tobacco producer, Serbia has to deal with large amounts of leftover tobacco stalks after harvesting. One option for this type of biomass is to burn it, but burning is not encouraged in Serbia, ...since the levels of its combustion products have not been investigated yet. The aim of this study was therefore to determine the elemental composition, ash and nicotine content, heat values, and composition of gaseous combustion products of tobacco stalk briquettes and to see if their mixing with other types of biomass available in Serbia could improve their ecological profile. We made 11 different types of briquettes: six of pure raw materials, including burley tobacco stalks, sunflower head remains, wheat straw, corncob, soy straw, and beech sawdust and five by mixing tobacco stalks with these other raw materials in a 50:50 mass ratio. All briquettes meet the ecological criteria regarding the emission limits for nitrogen oxides (NO
), sulphur dioxide, carbon monoxide, and carbon dioxide. Nicotine content in flue gases (<10 mg/kg) is far below the maximum level allowed by the European Union. Heat values of all biomass samples are acceptable, although lower than those specified for solid biofuels (≥16.0 MJ/kg), save for corncob and beech sawdust and their mixtures with tobacco stalks. Our findings therefore encourage the use of tobacco stalks as a viable biofuel.
Consumers are increasingly seeking foods that are rich in dietary fibre and wholegrains, but are often unwilling to compromise on sensory quality. Fibre- rich and wholegrain food reviews key research ...and best industry practice in the development of fibre-enriched and wholegrain products that efficiently meet customer requirements.Part one introduces the key issues surrounding the analysis, definition, regulation and health claims associated with dietary fibre and wholegrain foods. The links between wholegrain foods and health, the range of fibre dietary ingredients and a comparison of their technical functionality are discussed, as are consumption and consumer challenges of wholegrain foods. Part two goes on to explore dietary fibre sources, including wheat and non-wheat cereal dietary fibre ingredients, vegetable, fruit and potato fibres. Improving the quality of fibre-rich and wholegrain foods, including such cereal products as wholegrain bread, muffins, pasta and noodles, is the focus of part three. Fibre in extruded products is also investigated before part four reviews quality improvement of fibre-enriched dairy products, meat products, seafood, beverages and snack foods. Companion animal nutrition as affected by dietary fibre inclusion is discussed, before the book concludes with a consideration of soluble and insoluble fibre in infant nutrition.With its distinguished editors and international team of expert contributors, Fibre-rich and wholegrain foods provides a comprehensive guide to the field for researchers working in both the food industry and academia, as well as all those involved in the development, production and use of fibre-enriched and wholegrain foods. * Reviews key research and best industry practice in the development of fibre-enriched and wholegrain products * Considers analysis, definition, regulation and health claims associated with dietary fibre and wholegrain foods * Explores sources of dietary fibre including: wheat and non-wheat cereal, vegetable, fruit and potato fibres
The paper describes the production of an AlSi7Mg cast alloy with Li additions and the reactions of the melt with different moulding materials. It is known that Li is very reactive and tends to form ...various reaction products such as oxides, gases, etc., which can influence the casting quality. The aim of the research was to find a suitable way to produce such an alloy and to describe the reaction products that are formed between the melt and the moulding material and thus to find a suitable moulding material for processing Al cast alloys with Li additions. The melt was produced in an induction furnace under an inert atmosphere. After melting, 1 w/% Li was added and the melt was cast into five different mould materials consisting of graphite, steel, a CO2 sand mixture, Croning mixture and calcium silicate materials. In the last three cases, various alcohol-based coatings were also used, such as graphite, zirconium oxide-graphite coating and aluminate-graphite filler coating. The results showed that the reaction products in the form of powder on the casting surfaces and the gas porosity in the castings occurred in the cast of a calcium silicate mould and sand mould mixtures. In the case of graphite and steel moulds, the casting surfaces were not oxidised, with no reaction products, and no gas porosity.
As part of our OPENTOX project, we evaluated the incidence and mass concentrations of multiclass pesticide residues in 23 river/stream water samples collected in urban and agricultural areas of ...northwest Croatia at various points of the pesticide application season in 2015. The study included 16 compounds of five herbicide classes and seven compounds of three insecticide classes. Pesticide residues were accumulated from water by solid-phase extraction and analysed using high performance liquid chromatography with UV-diode array detection and/or gas chromatography-mass spectrometry. Herbicide residues were more common than the insecticide ones, and, as expected, they peaked in the middle of the application season. Metolachlor showed the highest concentrations and was found in 91 % of all samples, followed by terbuthylazine, found in 70 % of the samples. The highest total mass concentration of detected pesticides was measured in the water samples of the Krapina (3992 ng/L) and Sutla (3455 ng/L) collected in rural areas with intensive agriculture. Our findings strongly speak in favour of continued monitoring of surface waters and possibly extending the list of priority water pollutants.
The accelerated globalization of the food supply, coupled with toughening government standards, is putting global food production, distribution, and retail industries under a high-intensity ...spotlight. High-publicity cases about foodborne illnesses over recent years have heightened public awareness of food safety issues, and momentum has been building to find new ways to detect and identify foodborne pathogens and eliminate food-related infections and intoxications. This extensively revised 4e covers how the incidence and impact of foodborne diseases is determined, foodborne intoxications with an introduction noting common features among these diseases and control measures that are applicable before and after the basic foodstuff is harvested. * Providesa summary of the
Cilj ovog istraživanja bio je sačuvati kvalitetu i spriječiti oksidaciju boje, lipida i proteina u filetima pilećih prsa (mišić pectoralis major) tijekom skladištenja. U tu svrhu korištene su ...modificirane atmosfere (MA) s četiri različite mješavine plinova (vol. %) i to kisika (O2 ), ugljikovog dioksida (CO2 ) i dušika (N2 ). MA su bile: bez kisika (0: 20: 80), s niskim sadržajem kisika (20: 20: 60), sa srednjim sadržajem kisika (40: 20: 40) i atmosfera s visokim sadržajem kisika (70: 20: 10). Nakon 9 dana skladištenja u hladnjači pri 2 ± 1 °C izmjeren je pH, boja je ocijenjena instrumentalno i senzorski te su utvrđeni osnovni kemijski sastav, reaktivne tvari tiobarbiturne kiseline (TBAR) i proteinsko-karbonilni sadržaj sirovih pilećih prsa. Nakon termičkog tretmana (82 °C, 1 sat, sous-vide) pilećeg fileta ocijenjene su senzorne karakteristike mirisa i arome, a tekstura je izmjerena instrumentalno (Warner-Bratzler rezivim sječivom). Sastav smjese plinova utjecao je na sve parametre zavisne o oksidaciji: (i) boja: L* and b* vrijednosti bile su najviše pod svim MA s kisikom, s a* vrijednost pod MA bez kisika, sa srednjim i visokim sadržajem kisika, (ii) lipidi: TBAR su se znatno povećale pod MA s visokim sadržajem kisika nakon 7 dana skladištenja (ispod senzornih graničnih vrijednosti užeglosti), (iii) proteini: proteinsko-karbonilni sadržaj bio je najviši pod MA sa srednjim i visokim sadržajem kisika, i (iv) senzorne karakteristike: povećana je oksidacija boje i intenzitet neobičnih aroma pod svima MA s kisikom, kao i miris i aroma ustajalog pod MA bez kisika. Za pileća prsa najprikladnije je pakiranje s modificiranom atmosferom bez kisika jer je brzina oksidacije boje, lipida i proteina tijekom skladištenja bila najniža.
U sklopu našega projekta OPENTOX odredili smo masene koncentracije ostataka pesticida i njihovu učestalost u 23 uzorka vode rijeka/potoka u gradskim i ruralnim dijelovima sjeverozapadne Hrvatske, ...prikupljenih 2015. tijekom sezone njihove primjene. Istraživanje je obuhvatilo 16 spojeva iz pet različitih klasa herbicida i sedam spojeva iz triju klasa insekticida. Ostaci pesticida akumulirani su iz vode postupkom ekstrakcije na čvrstoj fazi i analizirani tekućinskom kromatografijom visoke djelotvornosti uz UV-detektor s nizom dioda ili vezanim sustavom plinske kromatografije I spektrometrije masa. Češće su detektirani ostatci herbicida nego insekticida, a najviše su koncentracije bile sredinom sezone njihove primjene. Metolaklor je određen u najvišoj koncentraciji i u najvećem broju uzoraka (91 %), a slijedio ga je terbutilazin, koji je nađen u 70 % uzoraka. Najviša ukupna razina određivanih pesticida bila je u uzorcima rijeka Krapine (3992 ng/L) i Sutle (3455 ng/L), koji su bili prikupljeni u ruralnom području s intenzivnom poljoprivredom. Rezultati našega istraživanja govore u prilog potrebi ne samo za kontinuiranim monitoringom pesticida u površinskim vodama nego i za proširenjem liste prioritetnih zagađivala.
In recent decades the modern food technology is based on the production of food that are nutritionally valuable and that their functional properties provide a positive effects on human health. ...Mustard is not just a spice that enriches the taste and smell to many foods, but it is also the foodstuff that greatly improves the metabolic system of a human body and its components contribute to the prevention of some diseases. Within this Ph.D. Dissertation a technological process of production of four kinds of mustard is optimized from the aspect of the aromatic complex formation. Mild mustard paste, mustard paste with herbs, barbecue mustard paste and chili mustard paste were produced. Before the start of production microbiological analyses were done on the raw materials. Quality control of the sunflower oil, which is a component in mustard paste, was analyzed as well. Each of the four samples was obtained after a detailed examination of series of test recipes, adjustment of the taste, aroma, color and consistency with the sensory evaluation team of professional tasters. The best samples were sensory evaluated and compared to the same type of mustard that can be found in the domestic market. Sensory evaluation was conducted with the descriptive analytical method, system of scoring. The results were statistically analyzed. All samples were analyzed by physico-chemical analyses, microbiological analyses, physical-chemical analyses of contaminants (the contents of pesticide residues, heavy metals and mycotoxins) and energy value of the sample. All results showed that the samples of four kinds of mustard were in accordance with the Regulation on quality and other requirements for mustard, Regulation on the quality and conditions of usage of additives in food and the other requirements for additives and their mixtures, Regulation on microbiological food safety in the market and Regulation on the amount of pesticides, metals and metalloids and other toxic substances, chemotherapeutics, anabolics and other substances which can be found in food. The purpose of the experiment was investigation of sinalbin degradation products in produced mild yellow mustard paste. The samples were extracted in a Soxhlet extraction system and analyzed by gas chromatography - mass spectrometry (GC-MS) techniques. The results were compared with the analysis of the ground white mustard seeds which were dominant fatty acids, originally present in the white mustard seeds, are also present in the mustard paste condiment made from this plant. The most abundant sinalbin degradation product in yellow mustard paste was 4-(hydroxymethyl)phenol. Other compounds identified in this sample were: 4-methyl phenol, 4-ethyl phenol, 4-(2-hydroxyethyl)phenol and 2-(4-hydroxyphenyl) ethanoic acid. 2-(4-Hydroxyphenyl) acetonitrile, one of the main degradation products of glucosinolate sinalbin, and one of the main precursors of 4-(2- hydroxyethyl)phenol during sinalbin degradation reaction, has not been detected in this sample, indicating that this compound is unstable under conditions used for semi-industrial production of this mustard paste condiment. The experiment was conducted with the aim to analyze the total profile of volatiles in white mustard seeds with a particular emphasis on the secondary lipid oxidation products of oil in this material. The samples were also extracted in a Soxhlet extraction system and analyzed by gas chromatography - mass spectrometry (GC-MS) techniques. The results showed those volatile compounds different from fatty acids represented less than 1 % of all compounds present in the extract. Sixteen volatile compounds were identified in the mustard seeds investigated. Besides the natural flavor compounds, a whole series of saturated and unsaturated aldehydes with one or two double bonds was identified: C6, C7, C8 and C9 alkanals; C7, C8, C9 and C10 2-enals and C7, C10 and C12 2,4-dienals. It was proven that unsaturated aldehydes (2-alkenals and 2,4-dienals), when present in high concentrations, can be indicators of an early stage of lipid oxidation in white mustard seeds.
Moderna prehrambena industrija se poslednjih decenija temelji na proizvodnji hrane koja je nutritivno vredna i koja svojim funkcionalnim svojstvima obezbeđuje pozitivan uticaj na zdravlje ljudi. Senf nije samo začin kojim se obogaćuju ukus i miris mnogim jelima, već je namirnica koja umnogome poboljšava metabolički sistem organizma i koja svojim komponentama doprinosi prevenciji nekih bolesti. U okviru ove doktorske disertacije optimizovan je tehnološki postupak proizvodnje četiri vrste senfa sa aspekta stvaranja aromatskog kompleksa. Proizvedeni su blagi senf, senf sa začinskim biljem, senf za roštilj i senf sa čilijem. Pre početka proizvodnje urađena su mikrobiološka ispitivanja sirovina koje ulaze u sastav receptura i kontrola kvaliteta suncokretovog ulja koje je komponenta u proizvodnji senfa. Svaki od ova četiri uzorka je dobijen nakon ispitivanja niza probnih receptura, korigovanjem ukusa, mirisa, boje i konzistencije uz senzorno ocenjivanje stručnog tima degustatora. Najbolji uzorci su senzorno ocenjivani i u odnosu na iste vrste senfa koji se mogu naći na domaćem tržištu. Senzorno ocenjivanje je obavljeno na osnovu deskriptivnog analitičkog bod sistema. Rezultati su statistički obrađeni. Na svim uzorcima su urađena fizičko-hemijska, mikrobiološka ispitivanja, kao i fizičkohemijska ispitivanja kontaminanata (sadržaj ostataka pesticida, teških metala i mikotoksina) i određena je energetska vrednost uzorka. Svi rezultati su pokazali da su uzorci četiri vrste senfa u skladu sa Pravilnikom o kvalitetu i drugim zahtevima za senf, Pravilnikom o kvalitetu i uslovima upotrebe aditiva u namirnicama i o drugim zahtevima za aditive i njihove mešavine, Pravilnikom o mikrobiološkoj ispravnosti namirnica u prometu i Pravilnikom o količinama pesticida, metala i metaloida i drugih otrovnih supstancija, hemioterapeutika, anabolika i drugih supstancija koje se mogu nalaziti u namirnicama. Eksperiment je imao za cilj da se izvrši analiza degradacionih produkata sinalbina u proizvedenom blagom senfu. Uzorci su ekstrahovani u Soxhlet-ovom sistemu, a potom analizirani metodama gasne hromatografije-masene spektrometrije. Rezultati su poređeni sa rezultatima mlevenog semena bele slačice koje je korišćeno u procesu proizvodnje senfa. Ovi rezultati ukazuju na to da su dominantne masne kiseline, prvobitno prisutne u semenu bele slačice takođe prisutne i u gotovom proizvodu, blagom senfu. Najobilniji degradacioni proizvod sinalbina u senfu bio je 4-(hidroksimetil)fenol. Druga identifikovana jedinjenja u senfu bila su: 4-metil fenol, 4-etil fenol, 4-(2-hidroksietil)fenol i 2-(4-hidroksifenil) etanska kiseline. Jedinjenje 2-(4-hidroksifenil)acetonitril, jedno od glavnih produkata degradacije glukozinolata sinalbina, i jedno od glavnih prekursora 4-(2-hidroksietil)fenola u reakciji degradacije sinalbina, nije otkriveno u ovom uzorku. To ukazuje da je ovo jedinjenje nestabilno u uslovima poluindustrijske proizvodnje senfa. Eksperiment je izveden sa ciljem da se analizira sastav isparljivih komponenata u semenu bele slačice sa posebnim osvrtom na sekundarne produkte oksidacije ulja u sirovini. Uzorci su takođe ekstrahovani u Soxhlet-ovom sistemu, a potom analizirani metodama gasne hromatografije-masene spektrometrije. Rezultati su pokazali da isparljiva jedinjenja, za razliku od masnih kiselina, predstavljaju manje od 1 % svih jedinjenja prisutnih u ekstraktu. Šesnaest isparljivih jedinjenja su identifikovana u ispitivanom uzorku mlevenog semena bele slačice. Pored jedinjenja koja prirodno daju aromu, identifikovan je čitav niz zasićenih i nezasićenih aldehida sa jednom ili dve dvogube veze: C6, C7, C8 i C9 alkanali; C7, C8, C9 i C10 2-enali i C7, C10 i C12 2, 4-dienali. Dokazano je da su nezasićeni aldehidi (2- alkenali i 2,4-dienali), kada su prisutni u visokim koncentracijama, indikatori rane faze oksidacije lipida u semenu bele slačice.
Cilj rada bio je odrediti značajke kvalitete i oksidacijsku stabilnost boje, lipida te bjelančevina (stvaranje karbonila) janjetine pakirane u vakuumu, starosti do 15 dana nakon klanja, pri stalnoj ...temperaturi od 2 °C ± 1 °C. Utvrđivana je primjerenost janjećeg filea (longissimus lumborum) za zrenje te optimalno vrijeme zrenja, a kojima se postižu najbolja senzorička svojstva, posebice mekoća i aroma. Uzorak od 100 g janjetine sadrži 23,48 g bjelančevina, 69,66 g vode i 5,48 g masti. Uzorci janjetine su bili najmekši 11 dana nakon klanja (senzorička procjena i mekoća utvrđena instrumentima – udio sile smanjen je za 61 %), pri čemu je najbolja aroma utvrđena 15 dana nakon klanja. Janjetina je starenjem postala značajno svjetlija i zasićenija (veće vrijednosti L*, a* i b*), povećao se sadržaj sekundarnih produkata oksidacije lipida (1,7 puta veća količina malondialdehida), dok se sadržaj proteinskih karbonila, po početnom povećanju zabilježenom 11 dana nakon klanja, smanjio na početnu vrijednost. U svrhu objektivnije procjene brzine oksidacije bjelančevina u janjetini, valja napomenuti da je sedmodnevno smrzavanje mesa prije analize značajno smanjilo sadržaj proteinskih karbonila (32 %). Utvrđeno je da je janjeći file primjeren za produženo zrenje, pri čemu optimalno trajanje zrenja filea iznosi 15 dana nakon klanja.
Glukozinolati su jedinstvena i važna skupina sekundarnih metabolita u nekim vrstama biljaka. Ubrajaju se u specifičnu skupinu kemijskih spojeva tzv. 'fitokemikalija' koja je zastupljena u 16 ...botaničkih porodica reda Capparales. Za prehranu ljudi najznačajnija je porodica
Brassicaceae u koju se ubrajaju kupus, brokula, cvjetača, prokulice, roktvica, repa, gorušica. U ovom radu obuhvatiti će se svi parametri koji vladaju u različitim stadijima od uzgoja do prerade povrća iz porodice Brassicaceae, na biodostupnost glukozinolata i njihovih
razgradnih produkata, i na zdravlje ljudi. Glukozinolati su kemijski stabilni sve dok ne dođu u kontakt s enzimom mirozinazom (β-tioglukozid glukohidrolaza; EC 3.2.1.147). Hidroliziraju se u niz biološki aktivnih tvari (izoticijanati, indol-3-karbinol). Osim što se konzumira svježe, povrće se vrlo često procesira, te ovisno o uvjetima prerade, prisutni glukozinolati se mogu razgraditi što može imati za posljedicu promjenu njihove biološke aktivnosti. Mnogobrojna
epidemiološka istraživanja dokazala su i potvrdila pozitivan učinak konzumiranja povrća iz porodice Brassicaceae, a time i unosa glukozinolata u ljudski organizam. U radu će biti obrađen mehanizam njihovog pozitivnog djelovanja (antifungalno, antibakterijsko, antioksidativno, antimutageno, antikancerogeno djelovanje). Osim što imaju pozitivan učinak u ljudskom organizmu, glukozinolati i njihovi razgradni produkti mogu imati i antinutritivni učinak, što je također potrebno uzeti u obzir, međutim, potrebno je provesti još istraživanja u tom smjeru.
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