Search

Osnovni namen naloge je bil analizirati vsebnost biogenih aminov v fermentiranih mokah volčjega boba, fižola in soje med spontano fermentacijo ter ob dodatku komercialne starter kulture Livendo LV1. Moke stročnic, ki smo jih fermentirali s starter kulturo, vsebujejo manj biogenih aminov, ki nastanejo z dekarboksilacijo aminokislin v primerjavi z vzorci, kjer je potekala spontana fermentacija. V večini primerov je vsebnost biogenih aminov po 48-urni fermentaciji večja kot po 24-urni fermentaciji. Kadaverin in putrescin se med fermentacijo akumulirata v vseh treh vrstah stročnic. V primeru spontane fermentacije moke volčjega boba se po 48 urah tvori veliko putrescina (3533 mg/kg), v primeru dodane starter kulture pa se po 48 urah akumulira le 8 mg/kg putrescina. V spontano fermentiranih mokah stročnic smo določili še tiramin (16-568 mg/kg), triptamin (6-232 mg/kg), feniletilamin (7-14 mg/kg), v enem vzorcu pa tudi histamin (77 mg/kg). Vsebnost poliaminov spermina in spermidina se s fermentacijo ni spremenila. V splošnem ima fermentirana moka volčjega boba največje vsebnosti gama-aminobutanojske kisline (2834 - 3833 mg/kg) in fenolnih antioksidantov (109 - 142 mmol troloks/kg), vsebuje pa tudi največ prostih aminoskupin (154 - 277 mmol aminoskupin/kg moke), ki se tvorijo s hidrolizo, v primerjavi s fermentirano moko fižola oziroma soje. The main purpose of the study was to analyze the content of biogenic amines in lupine, bean and soybean flour during spontaneous fermentation and during fermentation with the commercial starter culture LivendoTM LV1. Legume flours fermented with selected starter culture contain less biogenic amines formed by decarboxylation of amino acids, compared to spontaneous fermentation. In most cases, the content of biogenic amines after 48 hours of fermentation is higher than after 24 hours of fermentation. Cadaverine and putrescine accumulate in all three types of legumes during fermentation. In the case of spontaneously fermented lupine flour large amounts of putrescine (3533 mg/kg) are formed and much lower contents after fermentation with starter (8 mg/kg). Tyramine (16-568 mg/kg), tryptamine (6-232 mg/kg), phenylethylamine (7-14 mg/kg), and in one sample also histamine (77 mg/kg) were determined in spontaneously fermented legume flours. The content of the polyamines spermine and spermidine did not change with fermentation. In general, fermented lupine flour has the highest content of gamma-aminobutanoic acid (2834 - 3833 mg/kg), phenolic antioxidants (109 - 142 mmol trolox/kg) and free amino groups formed by protein hydrolysis (154 - 277 mmol AS/kg flour) compared to fermented bean or soybean flour.

Istraživanja u okviru ove disertacije obuhvataju karakterizaciju svežeg kupusa hibrida bravo i ispitivanje fizičko-hemijskih i mikrobioloških promena u toku fermentacije kupusa u glavicama. Dobijeni rezultati istraživanja daju doprinos razvoju baze naučnih znanja u vezi sa karakteristikama kupusa fermentisanog u industrijskim uslovima, pri različitim uslovima fermentacije: količina dodate soli, različite temperature fermentacije i primena starter kulture. Takođe je prikazana mogućnost primene zbira ranga razlika (eng. Sum of Ranking Differences, SRD), hijerarhijske klaster analize (eng. Hierarchical Cluster Analysis, HCA) i analize glavnih komponenata (eng. Principal Component Analysis, PCA) za opisivanje funkcionalne zavisnosti primenjenih parametara fermentacije i fizičkih, hemijskih i mikrobioloških karakteristika fermentisanog kupusa u glavicama, a sa ciljem određivanja optimalnih uslova fermentacije. The research within this thesis includes the characterization of fresh cabbage hybrid bravo heads and the examination of physic-chemical and microbiological changes during the cabbage heads fermentation. The obtained results contribute to the development of a scientific knowledge base related to the characteristics of fermented cabbage in industrial conditions, under different fermentation conditions: the amount of added salt, different fermentation temperatures and the application of starter culture. The possibility of applying Sum of Ranking Differences (SRD), Hierarchical Cluster Analysis (HCA) and Principal Component Analysis (PCA) is also presented in order to describe the functional dependence of the applied fermentation parameters and physical, chemical and microbiological characteristics of fermented cabbage heads, with the aim of determining the optimal fermentation conditions.

Istraživanja u okviru ove disertacije obuhvataju karakterizaciju svežeg kupusa hibrida bravo i ispitivanje fizičko-hemijskih i mikrobioloških promena u toku fermentacije kupusa u glavicama. Dobijeni rezultati istraživanja daju doprinos razvoju baze naučnih znanja u vezi sa karakteristikama kupusa fermentisanog u industrijskim uslovima, pri različitimuslovima fermentacije: količina dodate soli, različite temperature fermentacije i primena starter kulture. Takođe je prikazana mogućnost primene zbira ranga razlika (eng. Sum of Ranking Differences, SRD), hijerarhijske klaster analize (eng. Hierarchical Cluster Analysis, HCA) i analize glavnih komponenata (eng. Principal Component Analysis, PCA) za opisivanje funkcionalne zavisnosti primenjenih parametara fermentacije i fizičkih, hemijskih i mikrobioloških karakteristika fermentisanog kupusa u glavicama, a sa ciljem određivanja optimalnih uslova fermentacije., The research within this thesis includes the characterization of fresh cabbage hybrid bravo heads and the examination of physic-chemical and microbiological changes during the cabbage heads fermentation. The obtained results contribute to the development of a scientific knowledge base related to the characteristics of fermented cabbage in industrial conditions, under different fermentation conditions: the amount of added salt, different fermentation temperatures and the application of starter culture. The possibility of applying Sum of Ranking Differences (SRD), Hierarchical Cluster Analysis (HCA) and Principal Component Analysis (PCA) is also presented in order to describe the functional dependence of the applied fermentation parameters and physical, chemical and microbiological characteristics of fermented cabbage heads, with the aim of determining the optimal fermentation conditions.

Pozadina istraživanja. Sir iz mišine je tradicionalni sir koji se proizvodi u Hrvatskoj. Sirevi dobiveni sličnom tehnologijom proizvode se i u drugim zemljama, no njihov kemijski i mikrobiološki sastav varira među regijama. Tradicionalno se sir iz mišine proizvodi bez dodatka starter kultura. Dodatak korisnih probiotičkih kultura brojnim mliječnim proizvodima ima dokumentirane prednosti. Učinci probiotičkih bakterija na aromatske spojeve i senzorska svojstva tradicionalnih sireva nisu u potpunosti istraženi. Svrha je ovog istraživanja bila utvrditi senzorska svojstva i razlike u aromatskim profilima uzoraka sira iz mišine, proizvedenog na tradicionalan način, bez dodatka starter kultura, ili uz dodatak probiotičkih bakterija. Eksperimentalni pristup. U ovom je istraživanju sir iz mišine proizveden uz dodatak probiotičkih kultura Lactobacillus plantarum B i L. lactis ssp. lactis S1. Tijekom zrenja su mikroekstrakcijom na čvrstoj fazi pomoću plinske kromatografije-masene spektrometrije ispitani hlapljivi aromatski spojevi. Senzorska svojstva su ocijenili obučeni senzoričari, upoznati s tradicionalnim okusom sira iz mišine. Rezultati ispitivanja arome i senzorskih svojstava su zatim uspoređeni pomoću faktorske analize i analize glavnih sastavnica. Rezultati i zaključci. Kromatografskom su analizom utvrđene razlike u sastavu aromatskih spojeva i senzorskih svojstava sira proizvedenog pomoću starter kultura Lactobacillus i kontrolnog uzorka sira proizvedenog na tradicionalan način, bez dodatka starter kultura. Dodatak probiotičkih kultura L. plantarum B i L. lactis ssp. lactis S1 rezultirao je proizvodima s boljim senzorskim svojstvima i kemijskim profilom hlapljivih aromatskih spojeva. Novina i znanstveni doprinos. Ova studija istražuje primjenu prirodno prisutnih probiotičkih kultura kao starter kultura u proizvodnji sira iz mišine. Njihovi učinci na aromatske profile i senzorske karakteristike sira uspoređeni su po prvi put pomoću faktorske analize i analize glavnih sastavnica., Research background. Cheese in a sack is a traditional cheese produced in Croatia. Types of cheese with similar production technology are made in other countries but chemical and microbiological composition varies between regions. Traditionally, cheese in a sack is produced without the addition of starter cultures. Addition of beneficial probiotic cultures to numerous dairy products has documented advantages. Effects that the addition of probiotic bacteria to traditional cheese have on aroma compounds and sensory properties have not been fully investigated. The aim of this study is to determine the sensory properties and differences in the aromatic profiles between cheese samples ripened in a lambskin sack, produced traditionally without the addition of any starter culture, or with the addition of probiotic bacteria. Experimental approach. In this study, cheese in a sack was produced with the addition of probiotic cultures Lactobacillus plantarum B and L. lactis ssp. lactis S1. During ripening volatile aroma compounds were analysed with a solid-phase microextraction gas chromatography-mass spectrometry. Sensory properties were evaluated by trained tasters who are familiar with the traditional taste of the cheese from a sack. The results of aroma composition and taste scores were then compared using factorial and principal component analyses. Results and conclusions. Chromatography showed differences in the composition of aroma compounds and the sensory properties between the cheese produced with Lactobacillus starter cultures and the control cheese, traditionally produced without a starter culture. The addition of probiotic cultures L. plantarum B and L. lactis ssp. lactis S1 resulted in products with better sensory properties and chemical profile of volatile aromatic compounds. Novelty and scientific contribution. This study investigates the usage of naturally present probiotic cultures as starter cultures in cheese in a sack production. Their effects on aroma profiles and sensory characteristics have been compared for the first time using factorial and principal component analyses.

Bakterije mliječno-kiselog vrenja poboljšavaju organoleptička, hranjiva i fizikalno-kemijska svojstva tradicionalne hrane. U radu smo odabrali 31 fermentirani prehrambeni proizvod (na bazi mlijeka i povrća), kupljen u lokalnim dućanima u gradu Tucumán, Argentina, kao izvore bakterija mliječno-kiselog vrenja za dobivanje ukiseljenih proizvoda. Ispitana su tehnološka svojstva 64 izolata za koja se pretpostavilo da pripadaju vrsti Lactobacillus, a koji bi se mogli upotrijebiti u proizvodnji fermentirane hrane. Većina je sojeva imala dobro svojstvo zakiseljavanja (>0,04 pH jedinica po satu) i proteolitička svojstva (slobodne aminokiseline>1 mmol/L), proizvodila diacetil i/ili acetoin i bila otporna na prisutnost 4 % NaCl. Prema količini proizvedene kiseline i osmotoleranciji odabrali smo 6 bakterija i identificirali ih sekvenciranjem 16S rDNA (identičnost 97-100 %) kao: Lactobacillus rhamnosus CRL2159 i CRL2164, L. plantarum CRL2161 i CRL2162, te Weissella viridescens CRL2160 i W. paramesenteroides CRL2163. Zatim smo procijenili njihova svojstva bitna za proizvodnju ukiseljenog povrća. Pri pH-vrijednosti od 4,5 i u prisutnosti 7 % NaCl izolati L. plantarum CRL2162 i L. rhamnosus CRL2164 imali su najbolji rast i inhibicijski učinak na bakterije Escherichia coli i Listeria innocua. Nije zamijećen antagonizam između odabranih sojeva koji bi spriječio njihovu uporabu u mješovitim kulturama, dok njihova svojstva upućuju na zaključak da se mogu koristiti kao starter kulture u proizvodnji visokokvalitetnog fermentiranog povrća. Razvoj tih novih starter kultura mogao bi povećati kompetitivnost proizvoda iz Argentine i njihovu zastupljenost na tržištu konzerviranog povrća., Lactic acid bacteria (LAB) improve the organoleptic, nutritional and physicochemical properties of artisanal foods. In this study, we selected 31 fermented dairy and vegetable foods marketed in Tucumán city, Argentina, as sources of LAB for the production of pickles. Sixty-four isolates presumptively identified as Lactobacillus strains were screened for relevant technological properties for production of fermented foods. Most strains showed moderate to good acidification (>0.04 pH units/h) and proteolytic capabilities (free aminoacids >1 mmol/L), produced diacetyl and/or acetoin and were resistant to 4 % NaCl. Based on acid production and osmotolerance, we selected six LAB strains and identified them by 16S rDNA sequencing (97–100 % identity) as: Lactobacillus rhamnosus CRL2159 and CRL2164, L. plantarum CRL2161 and CRL2162, Weissella viridescens CRL2160 and W. paramesenteroides CRL2163. Relevant properties for pickle manufacturing were further assessed. At an initial pH=4.5 and 7 % NaCl, L. plantarum CRL2162 and L. rhamnosus CRL2164 performed the best with high growth and inhibitory activity against Escherichia coli and Listeria innocua. There was no obvious antagonism among the selected strains that would dismiss their use in mixed cultures. Properties of the selected LAB suggest their potential as starter cultures for obtaining standardized, fermented vegetable products of high quality. The development of these new industrial starters would increase the competitiveness of production and open the country’s frontiers in the canned vegetable market.

Cilj ispitivanja ove doktorske disertacije odnosio se na mogućnosti inaktivacije Yersinia enterocolitica u fermentisanim kobasicama. Za potrebe eksperimenta proizvedene su kobasice kontaminirane sa Yersinia enterocolitica, sa i bez dodate starter kulture. Kontrolne grupe kobasica nisu bile kontaminirane a proizvedene su takođe sa i bez dodate starter kulture. U toku zrenja praćene su promene mikrobiološkog statusa fermentisanih kobasica i fizičko- hemijskih osobina. Za sva ispitivanja korišćene su standardne metode. U fermentisanim kobasicama užeg i šireg dijametra sa i bez dodate starter kulture u toku zrenja broj bakterija Y. enterocolitica se smanjivao. Broj bakterija Y. enterocolitica bio je svih dana ispitivanja statistički značajno manji u uzorcima kobasica kojima je dodata starter kultura. U uzorcima kobasica užeg dijametra dvanaestog dana, a u uzorcima kobasica šireg dijametra dvadesetpetog dana zrenja nije utvrđeno prisustvo Y. enterocolitica. Prosečan broj enterobakterija u toku zrenja u uzorcima fermentisanih kobasica užeg i šireg dijametra se statistički značajno smanjivao i bio je izraženiji u uzorcima kobasica kontrolne i ogledne grupe sa dodatkom starter kultura. Kod kobasica užeg dijametra enterobakterije nisu dokazane dvanaestog dana, kao i na kraju procesa zrenja, a u uzorcima kobasica šireg dijametra enterobakterije nisu dokazane dvadesetpetog dana, kao i na kraju procesa zrenja. Prosečan broj aerobnih mezofilnih bakterija u uzorcima fermentisanih kobasica užeg, odnosno šireg dijametra je statistički značajno rastao do dvanaestog, odnosno do osamnaestog dana zrenja, a zatim se do kraja procesa zrenja statistički značajno smanjivao. Kao i kod broja aerobnih mezofilnih bakterija, tako je i broj bakterija mlečne kiseline u uzorcima fermentisanih kobasica užeg, odnosno šireg dijametra, statistički značajno rastao do dvanaestog, odnosno do osamnaestog dana zrenja, a zatim se do kraja procesa zrenja statistički značajno smanjivao. Vrednost pH svih ispitivanih grupa uzoraka fermentisanih kobasica se u toku procesa zrenja statistički značajno smanjivala i na kraju zrenja bila je statistički značajno niža u uzorcima kobasica šireg dijametra, odnosno kod uzoraka kobasica kod kojih su korišćene starter kulture. U toku procesa zrenja, kontrolnih i oglednih grupa uzoraka fermentisanih kobasica užeg i šireg dijametra aw vrednost se statistički značajno smanjivala i bila je manja u uzorcima kobasica u kojima su korišćene starter kulture. Na kraju proizvodnog procesa uzoraka fermentisanih kobasica kontrolnih, odnosno oglednih grupa, kobasica užeg i šireg dijametra nisu utvrđene značajnije razlike između ispitivanih hemijskih parametara kvaliteta kobasica. The aim of these doctoral dissertation concerned the possibility of inactivation of Yersinia enterocolitica in fermented sausages. For the purposes of the experiment produced sausages contaminated with Yersinia enterocolitica, with and without add starter culture. Control groups of sausages were not contaminated and are also produced with and without add starter culture. During ripening are accompanied by changes in the microbiological status of sausage and physical-chemical properties. For all tests, the standard method. The fermented sausages narrower and wider diameter with and without add starter culture during the ripening bacteria Y. enterocolitica decreased. The number of bacteria Y. enterocolitica was all the days of tests statistically significantly lower in samples of sausages which added starter cultures. In samples of sausages inner diameter of the twelfth day, and in samples of sausages wider diameter twenty-fifth day of ripening were not confirmed Y. enterocolitica. The average number of enterobacteria during ripening in samples of fermented sausages narrower and wider diameter significantly decreased and was more pronounced in samples of sausages control and experimental group with the addition of starter cultures. When the inner diameter of the sausage enterobacteria not proven the twelfth day, and at the end of the ripening process, and in samples of sausages wider diameter enterobacteria not proven twenty-fifth day as well as at the end of the ripening process. Average number of aerobic bacteria in samples of fermented sausages narrower, or wider diameter was significantly increased to twelve, or eighteen days to maturity, and then by the end of the ripening process significantly decreased. As with the aerobic mesophilic bacteria, so the number of lactic acid bacteria in samples of fermented sausages narrower, or wider diameter, significantly increased to twelve, or eighteen days to maturity, and then by the end of the ripening process significantly decreased. The pH value of all the tested groups of samples of fermented sausages during the ripening process significantly decreased at the end of ripening was significantly lower in samples of sausages wider diameter, or in samples of sausages in which the starter cultures used. During the ripening process, the control and experimental groups of samples of fermented sausages narrower and wider diameter aw value is significantly decreased and was lower in samples of sausages which were used starter culture. At the end of the production process control of samples of fermented sausages, and experimental groups, sausage narrower and wider diameter were no significant differences between the chemical parameters of the quality of sausages.

Svrha ovog rada bila je izolirati i odrediti autohtonu mikrobnu populaciju iz uzoraka riba (lubin i orada) i školjaka (dagnje i kamenice), ulovljenih u zimskom i ljetnom periodu u Jadranskom moru, kao izvor potencijalnih bioprotektivnih starter kultura. Iz uzoraka su izolirani prirodno prisutni sojevi bakterija mliječne kiseline (BMK) porasli na MRS i M17 agaru. Korištenjem biokemijskih (API) metoda identifikacije ustanovljena je prisutnost slijedećih bakterijskih vrsta: Lactobacillus delbrueckii, Lactobacillus plantarum, Lactobacillus helveticus, Leuconostoc mesenteroides, Lactococcus lactis i Pediococcus damnosus. The purpose of this study was to isolate and identificate the indigenous microbial population of samples from fishes (sea bass and sea bream) and shellfishes (mussels and oystres), caught in winter and summer period in the Adriatic Sea, as a source of potential bioprotective starter cultures. From the samples, naturally occurring strains of lactic acid bacteria (LAB) grew on MRS and M17 agar, were isolated. Using biochemical (API) methods of identification established the presence of the following bacteria species: Lactobacillus delbrueckii, Lactobacillus plantarum, Lactobacillus helveticus, Leuconostoc mesenteroides, Lactococcus lactis and Pediococcus damnosus.

Svrha ovog rada bila je izolirati autohtonu mikrobnu populaciju iz uzoraka slavonskih kulena proizvedenih na tradicionalan način u seoskim domaćinstvima. Autohtona mikrobna populacija izvor je sojeva za razvoj starter kultura koje će, između ostalog, utjecati na aromu i teksturu određenog tradicionalnog mesnog proizvoda. Dominantna mikrobna populacija sastojala se od bakterija mliječne kiseline (BMK) i to : Lactobacillus plantarum u dva uzorka, Lactobacillus delbrueckii u dva uzorka, te Leuconostoc mesenteroides i Lactobacillus acidophilus u po jednom uzorku kulena. Također, su prevladavale i bakterije iz roda Staphylococcus, tipični predstav- nici starter kultura za meso, i to: S. xylosus, S. warneri, S. lentus i S. auricularis u broju od 3,30-5,56 log10 CFU/g uzorka. U dva uzorka kulena izolirani su i kvasci, predstavnici starter kultura za meso: Candida famata. Kvasci su izolirani s površine ovoja i iz sredine kulena u broju 3,48 - 6,48 log10CFU/g. Sa površine 4 od 6 analiziranih kulena izolirane su plijesni iz roda Penicillium sp. i Aspergillus sp. S obzirom na prisutnost plijesni, u uzorcima kulena se određivala i prisutnost mikotoksina. Koncentracije mikotoksina bile su od 0,9 – 1,6 ppb za okratoksin A (OTA) i 0,1 – 0,5 ppb za aatoksin B1 (AFB1) te su osim u površinskom sloju, utvrđeni i u središtu kulena. U uzorcima kulena sa kojih nisu izolirane plijesni, nije dokazana ni prisutnost mikotoksina. Svi izolati BMK pokazali su znatno anti- mikrobno djelovanje prema patogenim test mikroorganizmima, te pokazali jedno od važnih svojstava potencijalnih starter kultura., The purpose of this study was to isolate the indigenous microbial population of samples from the Slavonian kulen produced in the traditional way in rural households. Autochthonous microbial population are potential starter cultures, which can be used to obtain top quality avour and texture certain traditional meat products. Dominant microbial populations consisted of lactic acid bacteria (LAB): L. plantarum (4,7log10CFU/g) in two samples, L. delbrueckii (3,0log10CFU/g) in two samples, L. mesenteroides (9,23log10CFU/g) and L. acidophilus (7,78 log10 CFU/g) in one sample of Slavonian kulen. The bacteria from the genus of Staphylococcus was also dominated microbial population in Slavonian kulen, the typical representatives of starter cultures for meat, as follows: S. xylosus, S. warneri, S. lentus and S. auricularis in number from 3.30 - 5.56 log10 CFU / g sample. From two samples of Slavonian kulen were isolated yeasts, representatives of starter cultures for meat: Candida famata. Yeasts were isolated from the surface and from the mid of Slavonian kulen in number from 3.48 to 6.48 log10 CFU / g. From the surface 4 of 6 analyzed kulen were isolated molds from the genus Penicillium sp. and Aspergillus sp. Considering the presence of mold in samples of Slavonian kulen, the presence of mycotoxins were also determined. Mycotoxin concentrations were 0.9 to 1.6 ppb for ochratoxin A (OTA) and 0.1 to 0.5 ppb for aatoxin B1 (AFB1) and were dened not only on the surface layer, but also in the centre of Slavonian kulen. In the samples of kulen which were not iso- lated molds, it was not proven the presence of mycotoxins. All LAB isolates showed signicant antimicrobial activity against tested pathogenic microorganisms, and showed one of the important properties of potential starter cultures.

Kombuha je tradicionalni napitak koji se dobija fermentacijom zaslađenog crnog ili zelenog čaja, fiziološkom aktivnošću čajne gljive, koja predstavlja simbiozu autohthonih vrsta kvasaca i bakterija sirćetnog vrenja. Cilj rada je bio da se ispita biološka aktivnost konzumnih kombuha napitaka (titrabilne kiselosti 3,5-4 g/L) od crnog čaja (Camellia sinensis L), čaja ehinacee (Echinacea purpurea L.) i rtanjskog čaja (Satureja montana L.). Za ispitivanje antimikrobne aktivnosti kombuha napitaka upotrebljeni su sledeći sojevi bakterija, kvasaca i plesni: Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus sp., Salmonella enteritidis, Proteus mirabilis, Escherichia coli, Sarcina lutea, Saccharomyces cerevisiae, Candida pseudotropicalis, Rhodotorula sp., Penicillium aurantiogriseum, Aspergillus niger i Aspergillus flavus. Antioksidativna aktivnost kombuha napitaka ispitana je na DPPH i OH radikale ESR spektralnom metodom. Antiproliferativna aktivnost čajeva i kombuha napitaka od crnog i rtanjskog čaja ispitana na tri ćelijske linije humanih karcinoma: HeLa (epitelni karcinom cerviksa), MCF-7 (adenokarcinom dojke) i HT-29 (adenokarcinom debelog creva). Pored istraživanja biološke aktivnosti kombuha napitaka, cilj rada je bio da se ispitaju i neki od osnovnih parametara kombuha fermentacije – optimalna količina izvora ugljenika i azota u medijumu za kultivaciju, geometrijske karakteristike fermentora, inokulacija starter kulturama. Definisanje kritičnih parametara kombuha fermentacije je bio osnov za izvođenje matematičkog modela za scale-up fermentativnog procesa. Kombucha is a traditional beverage obtained by fermenting sweetned black or green tea with tea fungus, which represents a symbiotic combination of acetic acid bacteria and autochthonous yeast species. In this study, the antimicrobial, antioxidative and antiproliferative activity of kombucha beverages (titratable acidity 3,5-4 g/L) obtain from black tea (Camellia sinensis L), echinacea tea (Echinacea purpurea L.) and rtanj tea (Satureja montana L.) were tested. Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus sp., Salmonella enteritidis, Proteus mirabilis, Escherichia coli, Sarcina lutea, Saccharomyces cerevisiae, Candida pseudotropicalis, Rhodotorula sp., Penicillium aurantiogriseum, Aspergillus niger i Aspergillus flavus were used as test microorganisms for examination of antimicrobial activity. The antioxidant activity of differently prepared kombucha beverages was examined agains DPPH and OH radicals by ESR-spectrometry. Antiproliferative activity of black tea kombucha and Satureja montana kokmbucka was measured by sulforhodamine B colorimetric assay on HeLa (cervix epitheloid carcinoma), HT-29 (colon adenocarcinoma), and MCF-7 (breast adenocarcinoma) cells line. Also, same parametars of kombucha fermentation – optimal quantity of source of carbon and nitrogen in cultivation medium, geometric characteristics of reactors and inoculation by starter culture – were tested. Definition of critical parameters of kombucha fermentation is important for derivation of mathematical model for scaling-up fermentation process.

The effect of two starter culture (B-3 and CH-1, Chr. Hansen's, Denmark) and some technological parameters on the viscosity and sensory properties on yogurt made from goat's milk was investigated. The obtained results showed that yogurt with B-3 culture had superior structure and the change in viscosity was very low during stirring and cooling. In both experiments an increase of viscosity was found during cold storage for 24 and 48 hours. Yogurt produced with B-3 cultures had a higher mean grade (4.58) and got 91.60% of total quality and yogurt produced with CH-1 had a lower mean grade (3.88) and got 77.60% of total quality. Kratak sadržaj: Istraživanja su obuhvatila ispitivanje uticaja dve vrste starter kulture (B-3 i CH-1, Chr. Hansen-Danska) i nekih tehnoloških operacija na viskozitet, kao i senzorne karakteristike jogurta od kozijeg mleka. Dobijeni rezultati su pokazali da je jogurt sa B-3 kulturom imao znatno bolju konzistenciju, a viskozitet se neznatno menjao za vreme razbijanja i hlađenja gela. Kod oba uzorka jogurta uočeno je povećanje viskoziteta za vreme čuvanja na temperaturi 4-6°C u toku 24 i 48 časova. Kad su senzorna svojstva u pitanju jogurt sa B-3 kulturom imao je veću prosečnu ocenu (4.58) i dobio je 91.60% od maksimalnog kvaliteta, dok je jogurt proizveden sa CH-1 kulturom imao nižu prosečnu ocenu (3.88) i dobio je 77.60% od maksimalnog kvaliteta.