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Wheat and barley have always been a valuable source of food. However, their susceptibility to Fusarium infections can gravely affect the malting and brewing processes by degrading and lowering the quality of malting cereals. Malting and brewing companies are especially sensitive to Fusarium infection since it causes great economic losses. The most important problem occurring with Fusarium fungi is that they produce mycotoxins, compounds toxic for humans and animals. Due to their water-soluble property, some of the mycotoxins are considered very important (deoxynivalenol, nivalenol, zearalenone, aflatoxins, fumonisins, ochratoxin A, etc.) in barley-to-beer-chain. They are regularly monitored even before the cereals enters the malting industry. Besides these regular mycotoxins, emerging, modified mycotoxins can be detected in beer in much higher concentrations and ratios than in other food. Modified mycotoxins can be described as conjugation products created through the detoxification mechanisms of living organisms. With the development of analytical methods, detection and quantification of very low concentrations of new mycotoxins in different foodstuffs is possible. The data base of known mycotoxins is getting bigger, but the health safety regulations are moving very slow in updating new compounds as potentially dangerous for humans and animals. However, even though the scientific community gives enough attention and space to mycotoxins that contaminate malt and beer, none of these mycotoxins have been regulated in beer so far. Given that beer is such a popular recreational drink, drank in every corner of the world, clear limits and especially regular and mandatory controls of mycotoxins in malt and beer should be introduced.

Consumers are becoming more interested in healthy nutrition. To meet consumer requirements, the possibility of the fruit and vegetable juice fermentation by bifidobacteria was investigated. Sour cherry, orange, carrot, and tomato juice was fermented with five Bifidobacterium strains (from human origin and starter culture). The tested strains have grown well in orange, carrot, and tomato juices. The B. longum Bb-46 strain demonstrated the best growth activities. It was found that ratio of the produced acetic and lactic acids are dependent on the Bifidobacterium strain rather than on the fermentation medium. The most intensive inhibition was observed against the Campylobacter jejuni strain. In course of the fermentation the antioxidant capacities slightly decreased, except when the orange juice was fermented with B. lactis Bb-12 and B. longum A4.8. The obtained results may contribute to the design of a novel functional food product.

Slacanac V., Lucan M., Hardi J., Krstanovic V., Koceva-Komlenic D . (2012): Fermentation of honey-sweetened soymilk with Bifidobacterium lactis Bb-12 and Bifidobacterium longum Bb-46: fermentation activity of bifidobacteria and in vitro antagonistic effect against Listeria monocytogenes FSL N1-017. Czech J. Food Sci., 30: 321–329. The influence of the honey addition on the fermentative activity of Bifidobacterium lactis Bb-12 and Bifidobacte rium longum Bb-46 in soymilk was determined. Additionally, the inhibitory potential of honey-sweetened fermented soymilk against Listeria monocytogenes strain was examined. Two monofloral honey types were added to soymilk before the fermentation: dark-coloured chestnut honey and light-coloured acacia honey. On the basis of our previous studies on cow and goat milks, the basic hypothesis of this study was that the addition of honey could influence the growth of Bifidobacterium lactis and Bifidobacterium longum during the fermentation of soymilk. The addition of honey also influenced the decrease of raffinose and stachyose contents during fermentation. Furthermore, a higher inhibitory potential was assumed against Listeria monocytogenes caused by the honey addition. The obtained results show that both types of honey influenced the fermentative activity and numbers of Bifidobacterium lactis Bb-12 and Bifidobacterium longum Bb-46 viable cells in soymilk. Chestnut honey strongly influenced the acidity increase during the soymilk fermentation. A disc assay showed that the development of the inhibition zones of the growth depended on the type and concentration of honey, as well as on the type of milk. The chestnut honey had generally a higher inhibitory effect than acacia honey.

The aim of this study was to determine the influence of goat's milk fermented by Bifidobacterium longum Bb-46 on pathogenic Staphylococcus aureus strain, as well as to determine the differences of inhibitory potential between fermented goat's and cow's milk. The results showed significantly higher inhibitory effect of fermented goat's milk on the growth of Staphylococcus aureus compared to that of fermented cow's milk. Fermented goat's milk inhibited the growth of Staphylococcus aureus during the whole fermentation period. In contrast to fermented goat's milk, weaker inhibitory effect of fermented cow's milk was observed only during the first phase of fermentation (incompletely fermented samples with higher pH values and lower number of viable cells of Bifidobacterium longum Bb-46). The obtained results suggested that there was no correlation between changes of pH or CFU of Bifidobacterium longum Bb-46 during fermentation and the inhibitory effect of fermented cow's and goat's milk. However, the results suggested some correlation between the inhibition of Staphylococcus aureus growth and the content of SCFA and MCFA in fermented cow's milk. At the same time, considerably higher amounts of all examined SCFA and MCFA were produced in goat's milk in all the phases of the fermentation process.

This study was carried out to determine the intensity of production of acetic acid, short (SCFA) and medium (MCFA) chain fatty acids in cow and goat milk fermented by the use of Bifidobacterium longum Bb-46. Amounts of SCFA and MCFA in fermented goat and cow milk were determined by the use of GC/FID method. Concentration of acetic acid in the samples of fermented goat and cow milk were measured using GC/MS method. Furthermore, the growth rates of Bifidobacterium longum Bb-46 and its fermentation activity in goat and cow milk were also determined. Obtained results suggest higher metabolic activity of Bifidobacterium longum Bb-46 in goat than in cow milk. Bifidobacterium longum Bb-46 grew better in goat than in cow milk. Consequently, pH values decreased more rapidly during the fermentation of goat milk. Contents of all the examined SCFA and MCFA, as well as of acetic acid, increased more rapidly in goat milk during the whole fermentation process.

Synthetic dyes have wide application in many industries such as pharmaceutical, cosmetic, textile, paper, leather, plastics etc. The presence of dyes in effluents (namely wastewater) of the above mentioned industries is a major concern due to their high thermal stability and photostability, i.e. their persistence in the environment for an extended period of time. Furthermore, they are recalcitrant towards removal during usually employed wastewater treatment methods. Many agricultural waste materials containing high proportion of cellulose have the ability to adsorb various dyes and represent a simple and low-cost method of coloured wastewater treatment. The aim of this study was to preliminary investigate different low-cost bioadsorbents for their potential to remove synthetic dyes malachite green (MG) and methylene blue (MB) from aqueous solutions. Six lignocellulosic waste materials, beech sawdust (Fagus sylvatica L.), oak sawdust (Quercus robur L.), poplar sawdust (Populus alba L.), sugar beet waste, apple pomace and spent beer grains were tested for their ability to remove MG and MB from 15 mg L-1 aqueous dye solutions at constant temperature of 25 °C. Activated carbon served as control. Adsorbents were soaked in dye solutions for 5 hours and samples were taken at 30 min intervals for spectrophotometric determination of colour removal. All tested adsorbents showed high colour removal capacity at 5 hours contact time for both used dyes (90.74 – 98.06 % and 94.26 – 100 % for MG and MB, respectively). The results indicate that used bioadsorbents demonstrated the potential to be used as adsorbents for efficient remediation of coloured wastewater.

The aim of this study was to use a predictive model to analyse the growth of a probiotic strain Bifidobacterium animalis subsp. lactis Bb-12 in cow’s, goat’s and soy milk. The Gompertz model was used, and the suitability of the model was estimated by the Schnute algorithm. Except for the analysis of Bifidobacterium animalis subsp. lactis Bb-12 growth, the Gompertz model was also used for the analysis of pH changes during the fermentation process. Experimental results, as well as the values of kinetic parameters obtained in this study, showed that the highest growth rate of Bifidobacterium animalis subsp. lactis Bb-12 was obtained in goat’s milk, and the lowest in soy milk. Contrary to the growth of Bifidobacterium animalis subsp. lactis Bb-12, pH decreased faster in soy milk than in cow’s milk. The highest rate of pH decrease was also observed in goat’s milk, which is in correspondence with results of various previous studies. The Gompertz model proved to be highly suitable for analysing the course and the fermentation kinetics in these three kinds of milk, and might be used to analyse the growth kinetics of other probiotic and starter cultures in milk., Cilj rada bio je upotrijebiti jedan od prediktivnih modela rasta bakterija za analizu rasta probiotičkog soja Bifidobacterium animalis subsp. lactis Bb-12 u kravljem, kozjem i sojinom mlijeku. Korišten je Gompertzov model, a prikladnost modela je procijenjena Schnuteovim algoritmom. Osim za analizu rasta Bifidobacterium animalis subsp. lactis Bb-12, Gompertzov model korišten je i za analizu kretanja pH vrijednosti tijekom fermentacije. Eksperimentalni rezultati, kao i vrijednosti kinetičkih parametara, dobiveni u ovom radu, pokazali su da je najveća brzina rasta Bifidobacterium animalis subsp. lactis Bb-12 bila u kozjem mlijeku, a najmanja u sojinom mlijeku. Suprotno u odnosu na rast Bifidobacterium animalis subsp. lactis Bb-12, pH vrijednost opadala je brže u sojinom mlijeku nego u kravljem. Najveći pad pH bio je također u kozjem mlijeku, što potvrđuju rezultati naših prethodnih studija kao i rezultati drugih autora. Gompertzov model pokazao se pogodnim za analizu tijeka i kinetike fermentacije u ove tri vrste mlijeka i može se koristiti za analizu kinetike rasta drugih probiotičkih i starter kultura u mlijeku.

Due to increasing consumer demands for more natural, tasty and healthy food, the traditional process of sourdough bread production has been enjoyed renewed success in recent years, (Brummer & Lorenz, 1991 ; Thiele et al., 2002 ; Lopez et al., 2003). The use of sourdoughs is a necessary prerequisite for the preparation of rye and rye-wheat combination breads (Hammes & Ganzle, 1998). The acidification process effected by the application of sourdoughs is mainly used to improve quality, taste and flavour of wheat breads (Brummer & Lorenz, 1991 ; Katina et al., 2006a ; Arendt et al., 2007), and the slow staling (Katina et al., 2006b ; Plessas et al., 2007). The addition of sourdough during production of wheat bread causes major changes in the dough characteristics (Clarke et al., 2002 ; Clarke et al., 2004 ; Ketabi et al., 2008), especially in the rheological properties of dough. The effect of the fermentation process of wheat doughs containing lactic acid bacteria are complex and depending on variations between sourdoughs. It regards on starter culture type, fermentation regime and used additives (Wehrle et al., 1997). Many of the effects of sourdough have been considered by pH value decrease which has been caused with organic acid production. Rheological properties, acidification and flavour development are the most important parameters in fermentation processes control. The rheological characteristics of dough have been changed with fermentation. Types of microorganisms, metabolic activity and time-dependent development pH value effect on rheological properties (Wehrle & Arendt, 1998). Acids strongly influence on the mixing properties of dough. Dough with lower pH require a slightly shorter mixing time and have less stability than dough with normal pH level (Hoseney, 1994). Changes in pH values caused by production of lactic acid also influence on the rheological properties of dough (Wehrle et al., 1997). Dough with containing acid has been characterized by increased phase angle and reduced complex modulus indicative of overmixing (Wehrle et al 1997). Small physical and chemical changes in the gluten network can result in significant changes in rheological properties. Clarke et al. (2002) were concluded that addition of sourdough prepared either from a single strain starter culture or a mixed strain starter culture had significant impact on the rheological properties of wheat flour dough. Koceva Komlenic et al (2010) investigated the influence of chemical and biological acidification on dough rheological properties. According to their experimental results, rheological properties strongly depend on acidification type. Dough with lower pH value showed less stability during mixing, decreased extensibility and gelatinization maximum. In general, the rheological properties of dough greatly improved when the sourdough was added.

Oksidacija lipida je prepoznata kao glavni problem u jestivim uljima, ona prouzrokuje važnu promjenu kemijskih, senzorskih i nutritivnih svojstava. U ovom radu istraživan je utjecaj prirodnih antioksidanasa (ekstrakt ružmarina Oxy’Less CS, ekstrakt zelenog čaja, ekstrakt nara 10) u udjelima od 0,04% i 0,1% na oksidacijsku stabilnost bučinog ulja i djevičanskog bučinog ulja. Oksidacijska stabilnost ulja, sa i bez dodanog prirodnog antioksidansa, ispitivana je primjenom Oven testa. Rezultati Oven testa prikazani su kao vrijednost peroksidnog broja (mmol O2 / kg) nakon određenog vremena držanja uzorka pri temperaturi od 63 °C, odnosno tijekom četiri dana trajanja testa. Rezultat istraživanja pokazuje da veću antioksidacijsku aktivnost ima ekstrakt ružmarina Oxy’Less CS kod obje koncentracije u odnosu na ekstrakt zelenog čaja i ekstrakt nara 10. Ispitivani prirodni antioksidansi dodani u udjelu 0,1% efikasnije štite ova ulja od oksidacije u odnosu na dodatak udjela 0,04%. Također, dodatkom prirodnih antioksidanasa postiže se veća uspješnost zaštite djevičanskog bučinog ulja od oksidacijskog kvarenja u odnosu na zaštitu bučinog ulja. Djevičansko bučino ulje pokazuje veću održivost ili stabilnost prema oksidacijskom kvarenju., Lipid oxidation has been recognised as the major problem affecting edible oils, as it is the cause of important deteriorative changes in their chemical, sensory and nutritional properties. This study researched the effect of natural antioxidants (rosemary extract Oxy’Less CS, green tea extract, pomegranate extract 10), in dosage of 0.04% and 0.1%, on the oxidative stability of pumpkin seed oil and virgin pumpkin seed oil. The oxidative stability of oil, with and without added natural antioxidant, was evaluated using the Oven test conditions. The results are expressed as peroxide number value (mmol O2 /kg) after keeping the sample for a certain period of time at temperature of 63°C, that is, within four days of the duration of the test. The result showed the highest antioxidant activity with rosemary extract Oxy’Less CS comparable to green tea extract and pomegranate extract 10 in both concentrations. Tested natural antioxidants added in dosage of 0.1% protect these oils from oxidation more effectively than dosage of 0.04%. Moreover, by adding natural antioxidants, the protection of virgin pumpkin seed oil from oxidative deterioration is increased comparable to the protection of pumpkin seed oil. Virgin pumpkin seed oil shows higher sustainability or stability to oxidative deterioration.

Caprine milk is a nutritional and therapeutic food. The unique and beneficial characteristics of caprine milk that are superior to bovine milk include: better digestibility ; greater buffering capacity ; fat globules that are smaller in diameter and better distributed in the milk emulsion ; higher content of short-chain fatty acids in the milk fat ; higher content of zinc, iron and magnesium ; stronger lactoperoxidase (antimicrobial) system as well as better immunological and antibacterial characteristics. The larger amounts of some minerals, such as calcium, zinc and magnesium, in caprine milk may influence the growth of lactic acid bacteria since they are a normal part of some enzymatic complexes involved in lactose fermentation. The higher whey protein content could also be significant because Lactobacillus acidophilus and bifidobacteria grow better in the presence of higher levels of some amino acids (valine, glycine, hystidine). The use of caprine and ovine milk in cheesemaking is well known, but the production of fermented caprine milk via probiotics has not yet been developed, although many studies have highlighted the requirements for production of that kind of healthy food. During fermentation caprine milk loses its characteristic ‘goaty’ taste, which is unacceptable to many consumers. Moreover, the nutritive value of caprine milk increases during fermentation. The rise in the number of goat farms in Croatia has created the need to find other products that can be produced using caprine milk. According to the present situation in Croatia, there is no real possibility of producing fermented caprine milk for the global market, but many studies of fermented caprine milk have been performed.

In general, lactobacilli are nonpathogenic part of the normal urogenital microflora and have been recognized as a barrier against colonization of unwanted (pathogen) microflora. The results of many in vitro studies suggest following mechanisms of probiotic lactobacilli action in urogenital tract: adhesion to urogenital cells, competition with pathogens for adhesive sites, production of biosurfactants, co-aggregation with pathogens, production of antimicrobial substances (organic acids, hydrogen peroxide and bacteriocins) and stimulation of immune system. From 80 different lactobacilli species isolated from human or animal intestinal and urogenital tract, only few lactobacilli strains possess optimal properties to be effective as probiotic therapeutics against infections in the urogenital tract. Combination of Lactobacillus rhamnosus GR-1 and Lactobacillus fermentum RC-14 was proposed as the best one for epithelial vaginal cells colonization and inhibition of uropathogens adhesion. The results of a number of clinical studies confirmed beneficial role of oral lactobacilli. However, the most of commercially available Lactobacillus strains, which are ordinary used in fermented dairy products, are seriously limited in protection of urogenital tract when they are ingested orally., Laktobacili su dio standardne nepatogene normalne urogenitalne mikroflore, koji djeluju kao barijera protiv kolonizacije nepoželjne (patogene) mikroflore. Prema rezultatima mnogih in vitro studija probiotički laktobacili u urogenitalnom traktu mogu djelovati putem sljedećih mehanizama: adhezija na stanice urogenitalnog trakta, natjecanje s patogenima za adhezivna mjesta, produkcija biosurfaktanata, koagregacija s patogenima, produkcija antimikrobnih supstancija (organske kiseline, vodikov peroksid i bakteriocini) i stimulacija imunološkog sustava. U urogenitalnom traktu samo nekoliko sojeva laktobacila, od 80 sojeva laktobacila koji su izolirani iz probavnog i urogenitalnog trakta, ima terapijska svojstva. U kolonizaciji epitelnih stanica vagine i sprječavanja adhezije patogena najuspješnijom se pokazala kombinacija bakterija Lactobacillus rhamnosus GR-1 i Lactobacillus fermentum RC-14. Rezultati niza kliničkih studija potvrdili su blagotvorni učinak oralnog unosa probiotičkih laktobacila. Međutim, najveći broj komercijalno dostupnih Lactobacillus sojeva, koji se uobičajeno koriste za fermentacije u mljekarskoj industriji, ukoliko se unesu oralno imaju limitirano zaštitno djelovanje u urogenitalnom traktu.

The aim of this study was to determine the stimulatory effect of honey addition on fermentation activity of Lactobacillus casei Lc-01 in cow’s and goat’s milk. Two monofloral honey types, dark-colored chestnut and light-colored acacia honey were added to cow’s and goat’s milk before the fermentation. Different mathematical and statistical models were used to describe the kinetics of fermentation in all analyzed samples. The basic hypothesis of this study was that addition of honey could have influence on the fermentation kinetics in both types of milk. Comprehensive kinetic analyses presented in this study suggest complex interaction between all components in fermented milk samples. The results presented in this paper show that addition of the both types of honey had stimulating effect on the growth of Lactobacillus casei Lc-01 in cow’s and goat’s milk. Addition of acacia honey statistically significantly higher stimulated the growth of Lactobacillus casei Lc-01 in cow’s and goat’s milk. This resulted in higher number of Lactobacillus casei cells, as well as in lower pH values of the samples with addition of acacia honey. Furthermore, goat’s milk fermented faster than cow’s milk. Calculated values of selected kinetic parameters show that critical period of the fermentation kinetics, when the honey influenced stimulatory, was between 10th and 20th hour of fermentation.

The aim of the study was to determine the influence of honey addition on fermentation of goat and cow milk with Bifidobacterium lactis Bb-12. Additionally, inhibitory potential of honey-sweetened fermented goat and cow milk against Listeria monocytogenes strain was examined. Two monofloral honey types, dark-colored chestnut and light-colored acacia honey were added. The basic hypothesis of this study was that addition of honey could have influence on the growth of Bifidobacterium lactis during the fermentation of goat and cow milk. Furthermore, higher inhibitory potential caused by honey addition against Listeria monocytogenes has been assumed. Compared to cow milk, higher acidity and CFU of Bifidobacterium lactis Bb-12 were noted in the fermented goat milk in all phases of the fermentation process. The results of this study show that both types of honey enhanced growth and acidity of the Bifidobacterium lactis Bb-12 in both milk types during fermentation. A disc assay has shown that development of growth inhibition zones depends on the type and concentration of honey, as well as on the milk type. The chestnut honey had generally higher inhibitory effect than acacia honey., U radu je ispitivan utjecaj dodatka meda na tijek fermentacije kozjega i kravljega mlijeka probiotičkom bakterijom Bifidobacterium lactis Bb- 12. Također, ispitivan je utjecaj medom zaslađenoga fermentiranoga kozjega i kravljeg mlijeka na inhibicijsko djelovanje rasta bakterije Listeria monocytogenes. Mlijeku su dodavane dvije vrste meda - tamna vrsta kestenova meda i svijetla vrsta bagremova meda. Osnovna pretpostavka u radu bila je da dodatak meda može utjecati na tijek fermentacije kozjega i kravljeg mlijeka, te na brzinu rasta Bifidobacterium lactis Bb-12 u mlijeku. Pretpostavljen je i jači inhibicijski učinak fermentiranog mlijeka na rast Listeria monocytogenes uzrokovan dodatkom meda mlijeku prije fermentacije. Rezultati ispitivanja pokazali su da obje vrste meda poboljšavaju rast i aktivnost Bifidobacterium lactis Bb-12 u obje vrste mlijeka tijekom fermentacije. Istovremeno, u kozjem je mlijeku tijekom cijelog razdoblja fermentacije zabilježena viša kiselost i veći broj stanica Bifidobacterium lactis Bb-12 nego u kravljem mlijeku. Testovi inhibicije rasta bakterije Listeria monocytogenes pokazali su da su veličine zona inhibicije ovisile o svim ispitivanim čimbenicima - vrsti mlijeka, vrsti dodanog meda, kao i o udjelu dodanog meda mlijeku prije fermentacije. Uzorci fermentiranog mlijeka s dodatkom kestenova meda jače su inhibirali rast bakterije Listeria monocytogenes nego uzorci s dodatkom bagremova meda.

Cilj rada bio je ispitati utjecaj fermentacije kozjeg i kravljeg mlijeka ABT- 2 kulturom na promjenu udjela pojedinačnih masnih kiselina u kozjem i kravljem mlijeku. Svrha rada bila je utvrditi povećanje udjela pojedinačnih kratko (SCFA - short chain fatty acids) i srednje (MCFA - middle chain fatty acids) lančanih masnih kiselina tijekom fermentacije kozjeg i kravljeg mlijeka. Hipoteza u radu bila je da veći udjeli SCFA i MCFA tijekom fermentacije ABT-2 kulturom nastaju u kozjem nego u kravljem mlijeku. Rezultati rada pokazali su da se fermentacijski procesi brže odvijaju u kozjem mlijeku u usporedbi s kravljim. Statistički značajno veći broj stanica probiotičkih bakterija Bifidobacterium spp. i Lactobacillus acidophilus La zabilježen je tijekom fermentacije kozjeg mlijeka, uz istodobno brže padanje pH vrijednosti kozjeg mlijeka u odnosu na kravlje. Uslijed fermentativne aktivnosti bifidobakterija iz ABT-2 kulture povećavao se udio SCFA i MCFA u obje vrste mlijeka. Međutim, značajno veći udio mjerenih SCFA i MCFA nastao je fermentacijom kozjeg mlijeka., In this paper, changes in composition and contents of each fatty acid during fermentation with ABT-2 culture were examined. The objective of this study was to determinate the increase of short (SCFA) and medium (MCFA) chain fatty acids in goat's and cow's milk during fermentation with ABT-2 culture. The hypothesis of this study was that higher contents of SCFA and MCFA are produced in goat's milk in comparison with cow's milk, during fermentation with ABT-2 culture. Obtained results have shown that fermentation process in goat's milk is faster than in cow's milk. The number of viable cells of probiotic bacteria Lactobacillus acidophilus La-5 and Bifidobacterium spp. was statistically greater in goat's milk than in cow's milk; consequently, pH value decreased more obviously in goat's milk than in cow's milk during whole fermentation process. Increase of SCFA and MCFA contents during fermentation was noted in both types of milk due to activity of bifidobacteria derived from ABT-2 culture. However, considerably higher amounts of examined SCFA and MCFA were produced in goat's milk than in cow's milk.

Reološka svojstva gruša su osnovni parametri kakvoće fermentiranih mliječnih napitaka. Na teksturalna svojstva fermentiranog mliječnog napitka utječe čitav niz činioca poput upotrijebljene starter kulture, sastava mlijeka, početne viskoznosti mlijeka, kinetike fermentacije (intenziteta pada pH vrijednosti), toplinskog tretmana mlijeka prije fermentacije, provedene homogenizacije itd. Svrha ovog rada bila je ispitati utjecaj tri činioca na kinetiku grušanja i reološka svojstva fermentiranog mliječnog napitka: udjela mliječne masti u mlijeku, upotrijebljene starter kulture i dodatka jakog bifidogenog prebiotika inulina. Rezultati rada pokazali su da sva tri faktora imaju utjecaj na kinetiku fermentacije i koagulacije, te teksturu gotovih proizvoda. Najveći utjecaj starter kulture je dobro poznat, a najinteresantniji je utjecaj dodatka inulina na povećanje konzistencije probiotičkih uzoraka priređenih od punomasnog mlijeka, Rheological properties of curd of fermented milk products are one of the basic factors of their overal quality. The textural (rheological) properties of fermented dairy products depend on the many different factors such as starter culture, milk composition, initial viscosity of milk, fermentation kinetics (intensity of pH value decrease), heat treatment of milk, homogenization etc. The aim of this paper was to examine the influence of three factors to coagulation kinetics and rheological properties of fermented milk product: milk fat content, starter culture and addition of inulin (a strong bifidogenic prebiotic). Results of this work indicated that all three factors have influence on fermentation and coagulation kinetics, as well as to textural quality of fermented milk products. The greatest influence of starter culture is well known, while the influence of inulin addition on consistency of probiotic samples increase was found to be the most interesting.

Cilj rada bio je usporediti reološke osobine gruševa kozjeg i kravljeg acidofilnog mlijeka uz dodatke, te ispitati neke fizikalne i reološke promjene tijekom njihovog skladištenja. Ispitivani su i utjecaji dodatka koncentrata voćnog soka jabuke na stabilnost gruša tijekom skladištenja, kao i njihov utjecaj na održivost proizvoda. Reološke osobine i pH vrijednost gruševa određivane su odmah nakon fermentacije, te poslije 3,6i9 dana skladištenja. Dodatkom obranog mlijeka u prahu povećavala se vrijednost koeficijenta konzistencije u kozjem i kravljem acidofilnom mlijeku. Skladištenjem uzoraka vrijednost koeficijenta konzistencije se povećavala do šestog dana skladištenja, a zatim se smanjivala osobito u kozjem acidofilnom mlijeku. U uzorcima priređenim s koncentratom soka jabuke vidno su bile izražene inhibicije tijekom fermentacije i koagulacije. Unatoč inhibicijama tijekom fermentacije i koagulacije dobiveni gruševi uzoraka priređenih sli 2% koncentrata soka jabuke su visoke kvalitete. Obzirom na pH vrijednosti izmjerene tijekom skladištenja, primijećeno je da koncentrat voćnog soka jabuke djeluje djelomično konzervirajuće na dobivene proizvode., The aim of this paper was to compare rheological properties of goat's and cow's acidophilus milk curds and also to determine physical and rheological changes during storage. The influence of apple juice concentrate addition on the shelf life and curd stability during storage was determined. Rheological properties and pH values of prepared curds were measured after the fermentation and after 3, 6 and 9 days of storage. With addition of skimmed milk powder the consistency coefficient value in goat's and cow's acidophilus milk increased until the sixth day of storage. After that consistency coefficient value was decreased, especially of goat acidophilus milk. Samples prepared with apple juice concentrate showed inhibitions during the fermentation and coagulation. In spite of inhibitions during the fermentation and coagulation, the obtained curds, prepared with 1 and 2per cent of apple juice concentrate, showed high quality. On the basis of pH values measured during the storage, it was noticed that the apple juice concentrate had a partly conservative effect on products.

U radu su praćene promjene reoloških parametara tijekom fermentacije kozjeg i kravljeg mlijeka bakterijom Lactobacillus acidophilus. Reološka svojstva gruša jedan su od osnovnih parametara kvalitete fermentiranih mliječnih proizvoda. Grušanje mlijeka odvija se uslijed snižavanja pH-vrijednosti tijekom fermentacije i uvjetovano je neutralizacijom i demineralizacijom kazeinskog kompleksa i otpuštanjem vode iz micelijske mreže kazeinata uslijed povećane koncentracije H+-iona. Promjene strukture gruša kozjeg i kravljeg mlijeka praćene su sa svrhom uspoređivanja s brzinama njihove fermentacije. I kozje i kravlje mlijeko nenewtonovske su tekućine, koje tijekom fermentacije postupno poprimaju izrazita svojstva karakteristična za pseudo-plastični (tiksotropni) tip tekućim. Formiranje gruša kod kozjeg i kravljeg acidofila započinje u trećem satu fermentacije. Pokazalo se da znatnije promjene reoloških svojstava kozjeg mlijeka nastupaju pri nižim pH vrijednostima od onih kravljeg, a porast prividnog viskoziteta kozjeg fermentiranog acidofilnog mlijeka je ujednačeniji i proporcionalniji padu pH vrijednosti tijekom fermentacije. Na kraju fermentacije kozje acidofilno mlijeko je prividno nižeg viskoziteta od kravljeg pri 22 °C. Tijekom tri dana čuvanja pri 4 °C značajno se poboljšavaju reološka svojstva kozjeg fermentiranog acidofilnog mlijeka koje postaje konzistentnije, dok je promjena konzistencije kravljeg acidofilnog mlijeka tijekom skladištenja neznatna., The changes of rheological properties during goat's and cow's milk fermentation using Lactobacillus acidophilus were observed in this paper. Rheological properties of curd are one of the basic parameters of fermented milk products quality. Milk curdling occurs as a consequence of the pH-value lowering during milk fermentation and it is the result of caseinat complex demineralisation and water molecules discharge from the lactic caseinate owing to the increase of H+-ions concentration. The differences in the curd structure between goat's and the cow's acidophilus milk were attended in the aim to compare those differences with fermentation velocities. Both of them, goat's and cow's acidophilus milk, are nonnewton fluids progressively obtaining characteristic properties of pseudoplastic (ticsotropic) type of fluids during fermentation. Goat's and cow's milk curdling starts in the third hour of fermentation. It was shown that extensive changes of goat's milk rheological properties were starting with the significantly lower pH-value than cow's milk and the increase of apparent viscosity is more steady in goat's acidophilus milk and it is proportional to pH-value fall during fermentation. At the end of the fermentation goat's acidophilus milk has lower apparent viscosity than cow's acidophilus milk at 22 °C. During three storage days at 4 °C Theological properties of goat's acidophilus milk were considerably improved (goats acidophilus milk became more consistent). During storage the consistency change of cow's acidophilus milk is minor.