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The food processing industry is advancing every day, and new food processing techniques and food safety standards are updated nearly daily. By acquiring up-to-date news in the field, and by the transfer of know-how knowledge it helps them to stay innovative, competitive in the market, with satisfied clients. This is one of the main advantages over competitors and helps them profit more from same ingredients for final products, with the usage of modern technologies, additives and by listening to the recommendations and requests of the market. Also one of the main issues, accept food quality, is food safety. Here all food processing household have to meet required food safety standards, to ensure the well-being for all of the consumers, and have proper arguments for health benefits statements. All of this can together with the newest food processing standards, can be learned by attending a lot of seminars and workshops, mandatory hygienic minimum or all can be learned at a modern and professional study of food technology.

Bacterial adhesion to fish surface and survival in gastrointestinal tract are essential characteristics in order to select probiotic candidate for aquaculture products. In our previous research we isolated Lactobacillus plantarum O1 from the gut of sea bream (Sparus aurata) and characterized it as plantaricin producer and bioprotective culture. This strain was successfully used for biopreservation of fresh sea bass (Dichentrarchus labrax), mussels (Mytilus galloprovincialis) and oysters (Ostrea edulis) with extension of shelf life to ten days and thirteen days, respectively. In order to characterize it as potential fish probiotic, L. plantarum O1 was examined for in vitro adhesion to sea bass mucus, survival in 10% sea bass bile and gastric contents as well as survival in sea water and hemolytic activity. Results showed good adhesion capacity to fish surface mucus as well as high survival rate in 10% bile and stomach content. L. plantarum O1 also withstood sea water environment and didn’t lyse red blood cells. These results suggest that L. plantarum O1 has potential application as fish probiotic and further studies are required to evaluate these properties in aquatic animals.

Traditionally donkey milk has been used as an alternative to human milk for infants or children mainly because of its similarities in nutrient composition, hypoallergenicity, immune modulation and antimicrobial activity. As a highly nutritious substrate it has a great potential for probiotic bacteria isolation. Beneficial health effects of probiotic bacteria used in functional foods and pharmaceutical products are based on the ability and capacity of these microorganisms in stimulation of host microbiota and immune system.Theaim of the study was to assess Lactobacillus plantarumM2’s probiotic potential through antimicrobial activity and immunomodulation potential. L. plantarumM2 was isolated from donkey milk and identified using biochemical and genetic tests. Antimicrobialactivity against several pathogens was determined using turbidimetric method. TNF-α production of LPS-stimulated human blood mononuclear cells (PBMC) was determined using commercial kit. L. plantarumM2 demonstrated great antimicrobial activity against all tested pathogens during 72h, namely S. aureus (96% inhibition), S. typhimurium (99% inhibition), L. monocytogenes (93% inhibition), C. utilis (48% inhibition)and E. coli(70% inhibition during 48 h). The LPS-stimulated PBMCs treated with L. plantarumM2 extracellular metabolites showed significant 66% suppression of TNF-α production (87.7 pg/mL compared to 262.5 pg/mL). Based on the results it can be assumed that donkey milk has a great potential as a source of probiotic bacteria contributing to the antimicrobial and anti-inflammatory human health benefits.

Mycotoxins are secondary metabolites toxic for humans and animals produced by some fungal species during their growth and, generally, released in to the growing media. Mycotoxigenic fungi can colonize a wide spectra of food and feed stuff and commodities like cereal seeds, fruits, meat and meat products. The toxic effects depend on a type of mycotoxin and vary from proven carcinogenic effects to cytotoxicity. Due to their high toxicity, only a dozen of mycotoxins are highly considered by legislators and scientist all over the world and their presence is food and feed is limited by legislations of almost all the countries. In traditional agriculture chemicals, such as antifungals and antioxidants, are widely used to control mycotoxin contamination of food and feed. This strategy could present severe environmental problems as well as a selection of resistant strains. Since many years the research of strategies and methods in mycotoxin control with lower environmental impact is ongoing. In this work some more environmental friendly methods to control the presence of mycotoxins in food and feed, like use of antagonistic strains or use of plant and mushroom extracts, are reviewed.

Beneficial health effects of lactic acid bacteria (LAB) used in functional foods and pharmaceutical products are based on the ability and capacity of these microorganisms in stimulation of host immune system. Health improving immune modulation and production of bioactive substances are restricted only to some LAB strains. In this study, peripheral blood mononuclear cells (PBMC) were stimulated with bacterial lipopolysaccharide (LPS) to produce pro-inflammatory cytokine tumor necrosis factor alpha (TNF-α). The aim of this study was to determine in vitro if extracellular bacterial metabolites, with molecular mass smaller than 2000 Da, from four selected LAB strains, suppress TNF-α production in LPS stimulated PBMC and therefore exhibit anti-inflammatory effect. Furthermore, cytotoxicity and genotoxicity of used bacterial culture media fractions containing these metabolites on PBMC was determined. Bacterial fractions showed no cytotoxicity or genotoxicity on PBMC, and all selected strains showed significant suppression of TNF-α production in LPS stimulated cells.

Mycotoxins are ubiquitous toxic secondary metabolites of filamentous fungi. They are unavoidable contaminants that are heavily dependant on the weather conditions. To be able to reduce the exposure to the mycotoxins usually, post-harvesting mycotoxin reduction techniques are used. One of such techniques is colour sorting. Accept the mycotoxins fungi are also producing the pigments as secondary metabolites, whose biosynthesis is triggered by the same molecular mechanisms due to proximity on the gene. The exact colour changes are connected to the mycotoxin-producing fungi. The Fusarium spp. is producing the red pigment rubrofusarin, and the yellow aurofusarin. The Aspergillus spp. are producing yellow Asperversin, and Neoaspergillic acid, or brown pigments. The Penicillium spp. are producing yellow Anthraquinone, or orange Purpurogenone. The one more significant mycotoxin producer with visible changes on the colour is Claviceps purpurea, the producer of ergot alkaloids. They are producing cereal like ergot sclerotia that are dark violet to black in colour. The change in colour is the main basis for the automated colour sorting and reduction of mycotoxin contamination. Laboratory colour sorting machine “Labseed” was used for colour sorting the infected seeds, and up to 95% of the mycotoxin concentration was reduced. The highest reduction was achieved with Ergot alkaloids, while method was least effective for reduction of ochratoxin A (68% reduction).

Dry-cured meat products are the oldest form of processed meat and very popular food around the world where different cultures contribute to their texture, flavor and safety. The production of dry.cured meat products goes back thousands of years because it was quickly discovered that drying meat reduce intrinsic moisture and thus prevent the activity of microorganisms and prolong product durability. Specific microbiota in dry-cured meat products involves complex microbial ecosystems that combine bacteria, yeast and molds which are responsible for many of the characteristics of these products. The most frequently isolated fungi from dry-cured meat products are from Penicillium, Aspergillus and Eurotium genera. For example P. crysogenum, P. commune, P. nalgiovense, P. olsonii, P. crustosum, A. Niger, A. fumigatus, A. ochraceus, E. repens. Some strains may produce highly toxic secondary metabolites, mycotoxins, and mold growth on sausage surfaces can lead to both desirable and undesirable effects. Preferred properties lead to the desired taste and texture of the product. The undesirable effects are usually connected to growth of undesirable molds which can lead to the defect in the quality and appearance. One of the possible solution is the use of the mold started culture which will prevent the growth of undesiravle wild mold population. The aim of this research was to isolate mold from fermented meat products in order to identify the indigenous flora of molds, the so-called houseflora. During the research, from 10 samples of dry-cured meat products, 3 different molds were isolated by classical microbiological methods. Each sample was inoculated in a 5 different mediums: Czapek yeast extract agar (CYA), malt extract agar (MEA), Sabouraud agar (SAB), Potato dextrose agar (PDA) and potato dextrose agar prepared by cooking potatos and adding agar. Samples were incubated for 5 days at 28°C. after the growth of molds, reverse and averse side of colonies are observed as well as color and exudate. Also the microscopic images were made. After obtaining microscopic images, samples were identified according to the identification key (Pitt and Hocking, 2009). Finally, analysing the results, it was concluded that isolated molds belong to Penicillium (2) and Aspergillus (1) genera and they show different growth on different medium under same cultivating conditions. These findings can be helpful for further identification of molds on dry-cured meat products.

The EU RASFF (Rapid Alert System for Food and Feed) system observed the significant presence of mycotoxins in food and feed. It is considered that 25% from the total quantity of produced food in the world, mainly of plant origin, are contaminated with mycotoxins. Due to their toxicity, it is important to control their presence and quantity in foods. Aflatoxin M1 is formed as the product of biological conversion of aflatoxin B1 in the mammary glands of mammals fed with fodder containing aflatoxin B group. Therefore, mycotoxins are entering in human food chain, not only through cereals and cereal products, but also through the meat, eggs, milk and dairy products. It is important to find accurate, reliable and efficient strategy for removal of inherent mycotoxins in food and/or fodder supplements. In this study, removal of mycotoxins with microbial cultures and their cellular components are imposed as an alternative to existing physical and chemical methods of detoxification. The project aims to explore the application of lactic acid bacteria (LAB) isolated from traditional dairy products and yeast cell components (β-glucan), and possible removal of resulting complex with mycotoxin from the milk. The research included quantification of the amount of AFM1 in milk samples using HPLC-FLD and LC-MS/MS followed by application of different concentrations of live and dead cells of LAB, lyophilized live and dead cells of LAB, as well as application of β- glucan (commercial and isolated from yeast cells). Formed biofixator - AFM1 complex was removed using the membrane filtration. Quality of milk regarding the quantity of macronutrients (fat, fatty acid composition, protein and carbohydrates and lactose) were determined.

Bakterije mliječne kiseline imaju pozitivan učinak na crijevnu mikrofloru ljudi i životinja što se manifestira smanjenjem rizika nastajanja raka debelog crijeva, smanjenjem infektivnih bolesti i drugo. Autohtona mikrobna populacija izvor je sojeva za razvoj starter kulutra koje utječu na aromu i teksturu određenog tradicionalnog proizvoda, a smanjuje se i vrijeme fermentacije proizvoda te osigurava bolja kvaliteta i trajnost proizvoda. Starter kulture i probiotičke kulture doprinose zaštiti i trajnosti proizvoda spriječavanjem rasta patogenih mikroorganizama, najčešćih kontaminanata u hrani, a tako formulirana hrana ima značajan potencijal u presonaliziranoj prehrani i zdravlju.

Lactobacillus plantarum O1 was isolated from gut of sea bream (Sparus aurata) and characterized in our previous research as plantaricin producer and bioprotective culture. Since there is lack of research regarding biopreservation with LAB of marine origin, we used L. plantarum O1 for biopreservation of most important comercial fish in Europe - sea bass (Dichentrarchus labrax) and shellfish- oysters (Ostrea edulis) and mussels (Mytilus galloprovincialis). Extension of shelf life, sensory, microbiological, and chemical freshness parameters of biopreserved aquaculture products were analyzed. The shelf life of live oysters and mussels treated with L. plantarum O1 bath was extended to thirteen days, while the control samples were not microbiologically suitable for the human consumption by the day three. Sea bass was treated with different methods. For ten days we kept the whole (ungutted) or gutted fish submerged in a bath with a solution containing L. plantarum O1 or we infused the solution into the digestive system of the fish through the mouth. Best results in terms of sensory score, pH, trimethylamine nitrogen levels, and antimicrobial action were achieved with bathing the whole fish, which extended the shelf life of the sea bass to ten days as compared to control, whose shelf life expired on day 3. Use of L. plantarum O1 as a biopreservative gives increased product safety as well as longer shelf-life. Therefore, these results represent new way of biopreservation of aquaculture products, with the addition of bacteriocinogenic strain isolated from marine environment.

Rezultati brojnih istraživanja ukazuju na to da ribe i školjkaši posjeduju različitu populaciju bakterija na koži, škrgama te u probavnom traktu. Pored toga, unutarnji organi (bubrezi, jetra i slezena) zdrave ribe mogu također sadržavati bakterije. Stoga je cilj ovog istraživanja bio izolirati i identificirati mikrobnu populaciju lubina (Dicentrarchus labrax), dagnji (Mytilus galloprovincialis) i kamenica (Ostrea edulis) Jadranskog mora tijekom zimskog perioda. Od ukupno 15 uzoraka 5 je uzoraka bilo kontaminirano bakterijama iz roda Vibrio, iz 4 uzorka je izolirana E. coli, 5 uzoraka su bila pozitivna na sulfitoreducirajuće klostridije dok je Pseudomonas aeruginosa dokazan samo u uzorcima dagnji i kamenica. U svim uzorcima lubina su dokazane enterobakterije. U niti jednom uzorku nije dokazana prisutnost bakterija iz roda Salmonella kao ni Listeria monocytogenes. Bakterije mliječne kiseline su izolirane iz samo jednog uzorka i to rod Lactobacillus. Fizikalno-kemijska analiza mesa ribe pokazala je da meso ima zadovoljavajući pH, histamin nije detektiran, odnosno koncentracija je bila ispod granice detekcije dok je koncentracija trimetilamina iznosila niskih 0, 801 mgN/100 g mesa.

AFM1 is an AFB1 derivate formed in the liver and is excreted in milk by the mammalian milk glands. Therefore, concerns about mycotoxins entering human food chain indirectly are well justified. In order to reduce the mycotoxins ratio, growth of molds should be reduced and that can be accomplished with good manufacturing practice (GMP). GMP alone is not sufficient to eliminate, inactivate and prevent fungal growth and toxin production so various physical and chemical methods are used. Lactic acid bacteria (LAB) are commonly used in feed production, in fermented product processes and are also known to extend the shelf-life of the product. Owing the ability of certain LAB strains to bind and neutralize mycotoxins, LAB are suggested as a potential novel biological method to reduce the toxicity of mycotoxins or prevent their absorption into the human body. Therefore, this study was carried out to investigate and compare the ability of viable, heat treated and lyophilized LAB cells to bind AFM1 in artificially contaminated milk. Depending on the used strain, incubation time and treatment of the cells, binding affinity of AFM1 by LAB cells was 23, 73-94, 49 %. Heat treated LAB cells showed highest ability (32- 94, 49 %) to bind AFM1, while lyophilized LAB cells showed lowest percentages of AFM1 binding. Obtained results indicate the importance of cellular treatment as they disturb the cell wall structure and consequently affect the ability to bind mycotoxins.

Aflatoxin M1 (AFM1), a hydroxylated metabolite of aflatoxin B1, is relatively stable molecule in raw and processed dairy products and cannot be inactivated by heat treatments such as pasteurization or sterilization. Due to the fact that presence of AFM1 in milk can be dangerous to human health and presents an enormous economic problem, there is an increasing emphasis on the development of methods for AFM1 reduction. One of the strategies is the use of various types of mycofixators (alumino-silicates, clay, zeolites etc.) that have the ability to bind mycotoxins and are removed from food after use. Despite the use of mycofixators in feedstuffs, AFM1 contaminated milk occurs. Therefore, the aim of this work was to determine the binding parameters of AFM1 in milk by β-glucan isolated from oats and yeast. Several concentrations of β-glucan were incubated in AFM1-contaminated milk during 24 hours. Binding efficiency was determined by quantifying the unbound AFM1 using (UP)LC-MS/MS method. Depending on these adsorbents the percentages of bound AFM1 varied from as low as 8, 2 % to as high as 65 %. Results also show noticeable nonlinearity during 24 hours when binding AFM1 with β-glucan from yeast compared to β-glucan from oats, which can be consequence of the reversible reaction of AFM1- β-glucan complex formation. β-glucan from oats has shown slightly better ability (65%) to bind AFM1 from artificailly contaminated milk compared to β-glucan isolated from yeast (63, 6%). These differences in binding ability are most likely due to the different structure and molecular branching of β-glucans.

Antioxidant activity of lactic acid bacteria (LAB) is associated with numerous health beneficial effects. In this study LAB were isolated from milk and different dairy products and 10 strains were identified using bichemical (API) tests and SDS-PAGE followed by molecular (PCR, RAPD) methods. Isolated strains of LAB were investigated for antioxidative activity as part of the classification for potential probiotics. Basic antioxidant parameters were measured to express the total antioxidant capacity of the selected isolates. Scavenging of 1, 1-diphenyl-2-picrylhydrazyl (DPPH) free radical was measured and glutathione and superoxide dismutase (SOD) activity was determined in intracellular cell-free extract of overnight bacterial culture. One SOD unit was defined as the amount of enzyme needed to exhibit 50% dismutation of the superoxide radical. Total glutathione was determined by colorimetric reaction of DTNB(5, 5' dithiobis(2-nitrobenzoic acid) reduction in overnight culture and in different culture conditions as well as under oxidative pressure. All isolated strains demonstrated antioxidative potential. High level of gluthatione was measured in 6 strains and significant SOD activity was determined in 5 isolates. Tested strains were categorized by measured activities and best were selected for multilayer microencapsulation as a part of functional food product.

The study focuses on developing novel cott age cheese containing spices with acceptable sensory properties, increased biological value and extended shelf life. Thirty types of cheese with added fresh or dried parsley, dill, pepper, garlic and rosemary were produced. Characterisation of phenolic compounds, antioxidant capacity and antibacterial activity of spices and cheese samples were evaluated. The cheese containing fresh pepper and fresh and dried herbs showed excellent sensory properties, with the best results obtained with fresh sweet red pepper. Dry rosemary had the highest antioxidant and antibacterial activity due to high mass fractions of caffeic and rosmarinic acids as well as high mass fractions of flavones and phenolic diterpenes. The plant extracts examined in vitro and in situ effectively reduce numbers of foodborne pathogens like Salmonella typhimurium, Escherichia coli, Staphylococcus aureus and Listeria monocytogenes, and therefore have potential as natural preservatives and antioxidants.

As customer awareness grows, there is an increasing consumer demand for minimally processed food products containing reduced amounts of additives. In order to preserve the safety and stability of foodstuffs, the use of preservatives is necessary in most cases, but their amounts can be reduced or they can be replaced by using alternative preservatives. There are numerous research findings in the scientific literature that support the antimicrobial effect, oxidative stability and scavenger abilities of black cumin seed oil. These properties, combined with its beneficial physiological effects, make it particularly suitable for use as a natural preservative. The goal of this work was to investigate the antimicrobial effect of black cumin seed oil in the case of Staphylococcus aureus, a pathogen relevant from a food safety point of view. In order to be able to map the mode of action more accurately, we worked with erythromycin, and to test the suitability of the oil in a combined preservation process, it was combined with organic acids.

Lactobacillus plantarum O1 was isolated from European sea bass (Dicentrarchus labrax) and identified by API, MALDI-TOF MS and electrospray LC-MS/MS method. As it showed strong antimicrobial activity on potential pathogens of concern to the fish industry, we tested it for the presence of bacteriocin by DGGE and LC-MS/MS method. Results demonstrate the presence of plantaricin NC8, confirmed by a positive MS2 peptide database match. Furthermore, during growth on DA-H medium, L. plantarum O1 showed no ability to produce histamine. Therefore, L. plantarum O1 was used for further biopreservation of sea bass, oysters and mussels. Previous studies provide no data relating to the biopreservation of fresh aquatic products by LABs from their natural microflora. Extension of shelf life, sensory, microbiological, and chemical freshness parameters of biopreserved aquaculture were analyzed. As compared to the control samples of fresh sea bass and molluscs that were microbiologically unsafe after third day, shelf-life of fresh sea bass was extended to ten days, while shelf-life of live oysters and mussels treated with a L. plantarum O1 bath was extended to thirteen days. The use of L. plantarum O1 as a biopreservative gives increased product safety, as well as a longer shelf-life and offers a better alternative for preserving sea foods.

Obzirom na trend zdrave prehrane, donedavno korištene kemijske metode kao osnovne metode konzerviranja sve su nepopularnije i traže se alternativni putevi konzerviranja na prirodan način primjenom bioprotektivnih kultura, najčešće bakterija mliječne kiseline (BMK) koje imaju GRAS status, prema EFSA i USFDA. Školjkaši i ribe u probavnom sustavu kao i sluzi sadrže korisne mikrobe koji se mogu koristiti za konzerviranje svježe ribe i živih školjkaša. Za bakterije mliječne kiseline poznato je da imaju pozitivan učinak na crijevnu mikrofloru u ljudi i životinja. Strogo definirani izolat BMK iskazuje probiotička i antimikrobna svojstva te se pokazao kao učinkovit biokonzervanas za akvatične proizvode.

Previous scientific studies indicated a need for further development of applying biological methods in the removal / binding or biotransformation of mycotoxins in food and feed. Such methods should inactivate mycotoxins without affecting the nutritional value and organoleptic properties of the product being processed. In practice, synthetic and natural zeolites are most commonly used as fodder additives, which effectively eliminate aflatoxin through adsorption ; however, the drawback is that necessary nutrients are also being absorbed in the process. Therefore, the microbial population from fresh cow's milk and traditional dairy products such as cottage cheese and cream was isolated and identified with the aim of selecting bioprotective cultures as biofixator for the removal of AFM1 from milk. One hundred and fifty colonies of LAB were isolated and identified by API tests and ten strains were confirmed with molecular (PCR) methods. All of the confirmed strains (Lactobacillus plantarum SM1, Lactobacillus helveticus S9, Lactococcus lactis 5MS1, Lactobacillus plantarum SMB, Lactobacillus plantarum SMA, Lactobacillus plantarum SS1, Lactobacillus paracasei KM, Lactobacillus rhamnosus KM, Lactobacillus plantarum KM, Lactobacillus plantarum MM)) were tested for possible removal/binding of AFM1 from milk. Therefore, one of the goals of the study was to implement the practical application of membrane filtration, with the possibility of removing the complex biofixator-AFM1 from milk and preserving the nutritional value of milk. The amount of unbound AFM1 was determined by HPLC.

Onečišćenje namirnica mikotoksinima predstavlja ozbiljnu prijetnju ljudskome zdravlju, napose kada je riječ o namirnicama koje se učestalo koriste u prehrani, a ujedno predstavljaju i značajan izvor mikotoksina. Postupcima prerade hrane može se postići smanjenje količine mikotoksina, njihova razgradnja, eliminacija ili transformacija u manje toksične derivate, ali potpuno uklanjanje mikotoksina iz prehrambenog lanca putem prerade je teško postići. Primjeni tehnika uklanjanja mikotoksina treba prethoditi utvrđivanje kemijskog sastava i toksičnosti nastalih produkta reakcije. U nedostatku potrebnih toksikoloških podataka, za oblike mikotoksina koji nastaju tijekom prerade hrane, treba pretpostaviti da imaju istu razinu toksičnosti, istu biološku raspoloživost i isti karcinogeni potencijal kao i izvorni spojevi. Prioritet za razvoj metoda smanjenja ili uklanjanja trebaju imati mikotoksini nepoželjnoga toksikološkoga profila koji se učestalo i u visokim koncentracijama pojavljuju u često konzumiranim namirnicama. Krajnji cilj primjene ovih metoda je sprječavanje štetnih učinaka mikotoksina po zdravlje potrošača kao posljedice izlaganja onečišćivačima iz hrane, pri čemu treba sačuvati hranjiva i organoleptička svojstva, kako sirovina, tako i gotovih proizvoda.

Data published insofar have shown that the presence of mycotoxins as frequent contaminants of different foodstuffs greatly varies dependent on many parameters of influence, such as the type of product, weather conditions, cultivation practices, and others. However, contradictory results have been reported regarding mycotoxins and the safety of organic and non-organic food products. The aim of this study was to investigate the co-occurrence of the most representative Fusarium mycotoxins such as zearalenone (ZEN), deoxynivalenol (DON) and fumonisins (FUM) in different organic cereal-based products (n = 85), produced from maize, wheat, oats and barley, and available on the Croatian market. ELISA methods validation showed the mean recovery rates to range from 88.3% to 101.2%, with the intermediate precision of 82.4% to 99.4% and variation coefficients (CV) of 5.4%-7.5% and 7.2%-11.4%, respectively. Maize by-products proved to be the most contaminated cereal products, with DON as the most represented Fusarium mycotoxin (32.8%) followed by FUM (24.5%) and ZEA (16.1%). Huge variations in mycotoxins concentrations were observed for all the cereal products, with the highest mean levels of 175.6±112.5 μg/kg for DON, 164.3±103.6 μg/kg for FUM and 32.8±28.4 μg/kg for ZEN determined in maize meal. Although in some samples the level of mycotoxins identified was higher than the maximum prescribed by legislation, based on the mean concentrations established in all cereal-based products, as well as given that the exposure assessment resulted in low percentages of the tolerable daily intake (TDI) with the maximum of 7.3% determined for ZEN, the investigated Fusarium mycotoxins found in organically produced cereal products do not pose as a human health hazard.

The aim of this research is to evaluate whether the well-defined autochthonous starter cultures survive controlled conditions (temperature, relative humidity) for industrial production of fermented sausage. Bacterial strains Lactobacillus plantarum 1K and Staphylococcus carnosus 4K1 were used as starter cultures for industrial sausage production. Effects of the added autochthonous functional starter cultures on microbiological and physicochemical properties and shelf-life of “Cajna sausage” were also monitored. Conventional culturing, isolation, identification by biochemical API and MALDI-TOF MS methods were applied to industrial sausage to define and monitor the viability of introduced autochthonous Lactobacillus and Staphylococcus strains. The obtained results indicated that the applied autochthonous starter cultures have better adapted to the meat environment and to the specific manufacturing process compared to the commercial starter cultures and they prolonged the shelf-life of the final product.

It is only since 1995 that the occurrence of ochratoxin A (OTA) in wine was recognized, and early provisional estimates suggested that 15% of the total OTA intake was due to wine consumption. OTA content was determined in white (n=20), red (n=35) and dessert (n=5) wines originating from different geographical regions in Croatia, and analysed using a validated ELISA method. Methodology validation showed the mean recovery rate of 92.1% with the intermediate precision of 91.1% and variation coefficients (CV)

The aim of the work was to investigate the possibility of spices and herbs application as economic natural antioxidants in the production of novel food products. Total phenol content, antioxidant capacity and microbiological quality are determined in dry and fresh parsley, dill, sweet red pepper, rosemary and garlic. Dry spices phenol content was 2-4 times higher than phenol content of fresh herbs. Phenolic content in herbs and spices increases in the following order: red pepper or garlic and then parsley, dill and rosemary. Among the tested spices, rosemary had the highest anti-radical capacity. The results of total antioxidant capacity and reducing power are in reasonable agreement with the content of phenol compounds, which also was confirmed by high correlation coefficients between TPC and reducing power. Majority of spices samples were of satisfactory or acceptable microbiological quality.

It is only since 1995 that the occurrence of ochratoxin A (OTA) in wine was recognized, and early provisional estimates suggested that 15% of the total OTA intake was due to wine consumption. OTA content was determined in white (n=20), red (n=35) and dessert (n=5) wines originating from different geographical regions in Croatia, and analysed using a validated ELISA method. Methodology validation showed the mean recovery rate of 92.1% with the intermediate precision of 91.1% and variation coefficients (CV)

Sir je visoko cijenjeni mliječni proizvod u mnogim zemljama svijeta, a posebna pažnja pridaje se tradicionalnim sirevima, koji nisu samo hrana već i dio kulture i obilježja neke zemlje. Zahvaljujući zemljopisnom položaju i klimatsko-vegetacijskoj raznolikosti Republike Hrvatske, u pojedinim regijama razvijena je proizvodnja različitih tradicionalnih sireva uz upotrebu začina. Kod proizvodnje sireva sa začinima, začini se dodaju ili u sir koji se potom oblikuje, ili se sir omata lišćem začinskog bilja, ponekad se začini nanose na površinu sira, a samo u rjeđim slučajevima začini se stavljaju u sam gruš. Dodatak začina u sirarstvu pridonosi poboljšanju senzorskih karakteristika, povećanju stabilnosti i roka trajanja sira te povećanju nutritivne vrijednosti sira. Kemijski sastav začina je kompleksan i svaki začin ima neki specifičan i dominantan sastojak koji pridonosi aromi proizvoda i/ili antimikrobnom i antioksidacijskom djelovanju začina. U ovom radu dan je pregled začinskog i aromatskog bilja kao prirodnih konzervansa koji se koriste u proizvodnji tradicionalnih sireva.

Tamna čokolada i napitci na bazi kakaovca prepoznati su kao sastavni dijelovi zdrave prehrane stoga je njihova kozumacija u porastu. Iako Uredba komisije (EZ) 1881/2006, sa svim izmjenama i dopunama (105/2010, 165/2010, 594/2012 i 1058/2012) ne spominje najveće dopuštene količine (NDK) aflatoksina (AF) i okratoksina A (OTA) u kakovcu i proizvodima na bazi kakaovca, ipak preporuča postavljanje dopuštenih količina za OTA od 1 μg/kg za čokoladu, čokoladu u prahu i tekuću čokoladu, te 2 μg/kg za sjeme kakaovca, kakao masu, kakaov kolač i kakaov prah. Stoga su u ovom radu provedene analize određivanja ukupnih AF i OTA u uzorcima tamne čokolade, koji su sadržavali od 32 do 99% kakaa bez ikakvih nadjeva i dodataka (orašastih plodova, suhog voća i dr.), kakao praha s 20% kakaa i napitcima na bazi kakao praha koji su sadržavali 15% kakaa. Upotrebom imunoenzimske ELISA metode (Enzyme-linked immunosorbent assay) proveden je „screening“ tržišta, kojim je dokazana prisutnost mikotoksina u čokoladama, kakao prahu i napitcima na bazi kakao praha u koncentracijama od 0, 1 do 1, 72 μg/kg za ukupne AF i od 0, 1 do 4, 24 μg/kg za OTA.

Ochratoxin A (OTA) is a nephrotoxic, immunosuppressive, teratogenic, and carcinogenic mycotoxin, secondary metabolite produced by species belonging to Aspergillus and Penicillium genera, mainly A. ochraceus, A. niger, A. carbonarius, and P. verrucosum. This ubiquitous mycotoxin is a contaminant of many foodstuffs, mainly cereals but also wine. The aim of this study was to assess how concentration of OTA affects the growth and morphological properties of selected yeast strains of Saccharomyces cerevisiae and Saccharomyces uvarum. The wine yeasts were exposed to a toxin-containing medium during 168 hours at 28°C. Determinations were carried out for the following parameters: cell count and cell diameter. regardless of its concentration in medium, OTA exerted a poor effect on the growth parameters of both yeasts. Obtained results show that in both yeasts (with and without added OTA) the lenght of lag phase was 4 h, the exponentional growth occured between 4 and 24 h, after which appears stationary phase which lasted until 168 h. Ochratoxin A changed morphological characteristics of S.cerevisiae and S.uvarum primary affecting cell diameter reduction. The biggest difference in the diameter was about 20 % in both yeasts, it was observed after 24 h of inoculation for the S.cerevisiae cells grown on OTA added media and after 48 h for S.uvarum cells. Both yeast strains developed a specific response to the influence of OTA which indicates that the toxicity of OTA was low or the yeasts have adapted to the presence of the contaminant.

Jaja se smatraju nutritivno cjelovitom namirnicom koja obogaćuje ljudsku prehranu, jer sadrže visokokvalitetne proteine, ugljikohidrate, lako probavljive masti i minerale, kao i vrijedne vitamine. Budući da u širokoj prodaji na našim prostorima, osim kokošjih, gotovo i nema jaja drugih vrsta peradi, a razlike se očituju u veličini, boji i težini jaja, kao i omjerima sastavnih dijelova (žumanjak, bjelanjak, ljuska) i hranjivih tvari (ugljikohidrati, proteini, masti, minerali), cilj ovog rada bio je usporediti sastav masnih kiselina, kemijski sastav te mikrobiološku ispravnost guščjih, pačjih, kokošjih i purećih jaja nabavljenih od istog malog domaćinstva. Srednja vrijednost aerobnih mezofilnih bakterija bila je 4, 55±0, 35 log CFU/g za guščja, 3, 73±0, 2 log CFU/g za pačja, 3, 79±0, 35 log CFU/g za kokošja te 4, 16±0, 3 log CFU/g za pureća jaja. Bakterije iz roda Salmonella i Listeria monocytogenes nisu dokazane ni u jednom uzorku jaja, dok su Enterobacteriaceae, Staphylococcus aureus, kvasci i plijesni dokazani u broju

Daily emergence of new aquaculture species and products on the world market is not motivated only by diversification of aquaculture products, but also by the demand for healthy products and safe food without the use of chemical preservation methods. Bio-preservation, as an innovative strategy, involves the use of natural preservatives which are safe for human consumption. Fish preservation by marinade is until now mainly used for the scombroid fish. A new product for flavoring and preservation of different types of fish and seafood with a specific organoleptic properties was developed during this study in the form of marinade on the basis of bitter orange (Citrus aurantium L.). The main preservative effect was achieved with L. plantarum O1 DSM32196 that was isolated from natural micro flora of sea bream digestive system. The preservation efficiency of different concentrations of L. plantarum O1 DSM32196 in marinated sea bass fillets stored for two weeks at the temperature of +4°C to +8 °C was compared with the conservation efficiency of L. plantarum ATCC under the same storage conditions. Total count (cfu/g) of Vibrio sp., E. coli, total coliforms, lactic acid bacteria and the concentration of histamine (mg/100 g) in marinated fillets were analyzed every day during the storage period for the efficiency evaluation. Furthermore, the pH of the meat and marinade was measured every day. The preservation efficiency of marinade that contained L. plantarum O1 DSM32196 was significantly higher in comparison to that which contained L. plantarum ATCC. The shelf life of this product was extended to two week period. According to the results of this study, the highest shelf-life can be achieved with the following formulation: 65-75% of 1, 5-2, 5% brine solution, 20-25% bitter orange juice , 1, 5-2% mixture of spices (dry leaf of laurel, Laurus nobilis L. ; dry leaf of sage, Salvia officinalis L. ; dry leaf of rosemary, Rosmarinus officinalis L.) ; black pepper, Piper nigrum L. ; cayenne pepper, Capsicum annuum L. ; dry, row or extract of garlic, Allium sativum L.) and 1, 5 – 2% suspension of Lactobacillus plantarum O1 DSM32196 in sterile physiological solution in concentration of 1x103-1x108 cfu/ml.

Ochratoxin A (OTA), a frequent contaminant of many foodstuffs including cereals and wine, is a mycotoxin produced as a secondary metabolite by several toxigenic molds belonging to Aspergillus and Penicillum species. The role of wine yeast in removal of this toxin from wine has been reported by different authors. The aim of the study was to examine whether and how OTA influences growth parameters of selected wine yeast strains Saccharomyces cerevisiae and Saccharomyces uvarum. Experiments were conducted using uncontaminated and toxin-containing medium and inoculated with yeast inoculum of a concentration amounting to 106 cfu/mL. The samples were analyzed periodically to assess final cell number and cell diameter during seven days at 28oC. Obtained results show that in both yeasts the differences between the final cell number in the medium with OTA and the control were not statistically significant. Ochratoxin A primary affected cell diameter reduction (up to 20%) both of S. cerevisiae and S. uvarum. Monitoring of oxidative status of yeast cells, through FOX assay and activities of superoxide dismutase, catalase and glutathione peroxidase, showed that ochratoxin A influences oxidative stress in yeast cells. Whether the changes in oxidative status are connected with impaired yeast growth is still object of study.

Biopreservation is a powerful and natural tool to increase sustainability and improve food security by using naturally occurring microorganisms and / or their inherent antibacterial compounds. In this context, lactic acid bacteria (LAB) have great possibility for the application in biopreservation because most of them have GRAS (Generally Recognized As Safe) status and naturaly dominate in microflora of many foods. Antagonistic and inhibitory properties of LAB are caused by different factors such as competition for nutrients, production of one or more antimicrobial active metabolites such as organic acids (mainly lactic and acetic acid), hydrogen peroxide, and antimicrobial peptides (bacteriocins). The aim of this study was to isolate and identify dominant microbial population of sea bass (Dicentrarchus labrax), oysters and mussels, to conduct biopreservation with isolated LAB and determine microbiological quality and extended shelf life. From a total of 14 samples of fish and shellfish five strains of LAB were isolated and identified: Lactobacillus plantarum O1, Lactobacillus helveticus O9, Leuconostoc mesenteroides L4A, L. plantarum K4 and L. plantarum D1. Biopreservation was conducted with the aforementioned bacteria along with monitoring of microbiological safety. L. plantarum O1 was proven as the best strain which extended shelf life of fresh sea bass to ten days compared to control sample that was microbiologically defective after the third day. Shelf life of oysters was extended to thirteen days and mussels to five days with the addition of LAB while control sample was improper after two, respectively three days.

Mycotoxins are secondary products formed in the metabolic process of molds and can have carcinogenic, mutagenic, immunotoxic and teratogenic properties. Aflatoxins are well known and most toxic natural mycotoxins, produced by many species of Aspergillus fungi, mainly A. flavus and A. parasiticus. Aflatoxin B1 (AB1) is the most toxic compound from the group and is a common contaminant in a variety of foods including peanuts, corn, rice, wheat and other grains as well as animal feeds. AB1 is classified as group 1 carcinogen by IARC classification. Ochratoxin A (OTA) is a mycotoxin produced by several species of Aspergillus and Penicillium fungi. OTA is detected worldwide in various food and feed sources such as cereals, coffee, spices, cocoa and their processed products. Because of its hazard to human and animal health, OTA has received increased attention worldwide. IARC has classified OTA as a group 2B carcinogen. Lactic acid bacteria used in fermented dairy products as a starter culture may have a role in the reduction of aflatoxin in foods and nutrients. The aim of this study was to assess whether and how presence of AB1 and OTA affects the growth and morphological properties of selected lactic acid bacteria, Lactobacillus plantarum. L. plantarum was exposed to a toxin- containing medium during 72 hours at 37°C. In presence of both toxins, L. plantarum entered exponential phase of growth after 2 hours. Stationary phase, in presence of OTA started after 4 hours, and in presence of AB1 after 6 hours. In presence of both AB1 and OTA morphological characteristics of L. plantarum were changed. Length and width of the cells in media with toxins was reduced. The biggest difference in length for L. plantarum was observed after 72 hours and was 22% in AB1 containing medium and 16% in OTA containing medium. While biggest difference in width for L. plantarum was observed after 48 hours and was 15% in both toxin-containing mediums

Moulds belonging to Aspergillus genus, mainly A. flavus, A. niger and A. parasiticus, are among the most important representatives that cause spoilage of food and feed products. The growth of fungi in foods or feeds is inhibited with application of different technological processes and various chemical additives. One of technologies that could prevent the growth of mould is radiation technology that uses ionizing radiation. This effective technology is widely used in food processes to destroy pathogenic and spoilage microorganisms without compromising the safety, nutritional properties and sensory quality of the food.

Ultrasonication is a non‐thermal method in food processing that has the advantage of preserving fruit juices without causing the common side‐ effects associated with conventional heat treatments. Special attention was drawn to Alicyclobacillus acidoterrestris that can be found in concentrated fruit juices and which it is very difficult to inactivate by heat treatment proceedings. The purpose of this study was to investigate the effect of non‐ thermal technology, high power ultrasound (HPU) on inactivation of Aspergillus ochraceus 318, Penicillium expansum 565, Rhodotorula sp. 74, Saccharomyces cerevisiae 5 and Alicyclobacillus acidoterrestris DSM 3922 in clear juices and nectars made cranberry juice concentrate. Inoculated juice and nectars were treated by high power ultrasound (20 kHz) according to procedure set by central composite design (CCD). Three operational parameters, amplitude (60, 90 and 120 μm), temperature (20, 40 and 60oC), and treatment time (3, 6 or 9 min) were varied in order to observe the influence of ultrasound and combination of ultrasound and slight heating (thermosonication) on growth and inactivation of selected microorganisms. Number of vegetative cells of A. acidoterrestris DSM 3922 were not significantly reduced by high power ultrasound (p>0.05). Contrary to expectations there was a growth activation of A. acidoterrestris DSM 3922. The value of reduction of cells of selected yeasts and moulds for ultrasound treatments at 60°C and the duration of the 3, 6 and 9 minutes ranged from 4.580 to 5.869 log units, depending on the initial number of selected yeasts and moulds before treatment. The effect of ultrasound was mainly attributed to physical (cavitation, mechanical effects, micro‐mechanical shocks) and/or chemical effects due to formation of free radicals (H+ and OH‐ due to sonochemical reaction) formed by the decomposition of water inside the oscillating bubbles. Power ultrasound caused complete inactivation of the growth of yeasts and moulds at 60 °C and treatment times of 3, 6 and 9 minutes, regardless of the value of the amplitude. Number of vegetative cells of A. acidoterrestris were not reduced.

U radu je ispitan utjecaj dodatka, iz kulena izolirane i karakterizirane, autohtone bakterijske starter kulture (ASK) na proces fermentacije i kvalitetu Slavonskog kulena proizvedenog prema tradicionalnom tehnološkom postupku i recepturi. Autohtona bakterijska starter kultura bila je pripremljena kao liofilizirana smjesa (w/w = 1/1) krioprotektora obranog mlijeka u prahu i bakterijskih kultura sljedećeg sastava: Lactobacillus plantarum 1K, u koncentraciji od 1∙109 - 1∙1010 cfu/g, Staphylococcus carnosus 4K1, u koncentraciji od 1∙108 - 1∙109 cfu/g i Staphylococcus carnosus 12ST, u koncentraciji od 1∙108 - 1∙109 cfu/g. Pripremljeno je tri skupine uzoraka Slavonskog kulena: referentni uzorci bez dodatka ASK-a i šećera, uzorci s ASK-om i 0, 8% glukoze te uzorci s ASK-om i 0, 8% maltodekstrina. U različitim proizvodnim fazama provedene su fizikalno-kemijske, mikrobiološke i senzorske analize te kontinuirano mjerene pH vrijednosti. Rezultati provedenih analiza pokazali su da dodatak autohtone starter kulture te 0, 8% glukoze i maltodekstrina u odnosu na referentni uzorak Slavonskog kulena, skraćuju vrijeme fermentacije i zrenja, a već nakon 3 mjeseca zrenja postižu optimalna senzorska svojstva bez promjene mirisa, okusa, boje i teksture specifične za Slavonski kulen, odnosno referentni uzorak proizveden prema tradicionalnoj recepturi. Veća koncentracija bakterija mliječne kiseline (BMK) te postignute niže vrijednosti pH uzoraka s dodatkom ASK-a i glukoze (pH = 4, 42), odnosno ASK-a i maltodekstrina (pH = 4, 52) tijekom procesa fermentacije u odnosu na referentni uzorak (pH = 5, 3), povećava sigurnost i trajnost Slavonskog kulena.

Many microorganisms like yeasts, molds and bacteria can reduce or modify ochratoxin A (OTA) present in food and feed. The application of microorganisms as mycotoxin binders highly depends on stability of the microorganism-mycotoxin complex. The most important feature for mycotoxins binding is the specific surface properties of the microorganisms, cell physiology and properties of mycotoxins like polarity, solubility, shape and charge distribution. It is well known that bacterium Gluconobacter oxydans is able to degrade patulin but has not been tested previously for their ability to bind OTA. Therefore the main objective of the study was to determine if the G. oxydans can bound OTA using viable and heat-treated cells. The method used for quantitative determination of OTA was immunoassay ELISA method, whereas method used for confirmation of the OTA presence included more specific detection technique liquid chromatography tandem mass spectrometry (LC-MS/MS). Obtained results show that G. oxydans bound OTA efficiently, although binding percentages for the heat-treated cells were below the values obtained for viable cells. In experiments with heat-treated cells binding capacity of OTA decreased from 80.8 to 30.4%. Influence on the changes of the tested strain surface properties was investigated by Fourier Transform Infrared Spectroscopy (FT-IR) presenting technique to obtain spectra from a very wide range of different compounds and to identify types of chemical bonds in a molecule. FT-IR analysis showed that the cell wall plays a key role in OTA adsorption. The most significant difference in the FT-IR spectra of blank biomass and G. oxydans biomass loaded with OTA was observed in the region of proteins (amide A, amide I and amide II band of proteins).

Fuzarijski mikotoksini, među kojima su najzastupljeniji zearalenon, deoksinivalenol, fumonizini i T-2 toksin, su česti onečišćivaći hrane i hrane za životinje, primarno žitarica i njihovih proizvoda. Onečišćenje hrane fuzarijskim mikotoksinima može uzrokovati brojne kronične i akutne toksične učinke u ljudi i životinja. Razina onečišćenja ovisna je o brojnim čimbenicima, započinje još na polju i moguća je u svim fazama proizvodnje hrane “od polja do stola”, uključujući skladištenje, te varira s obzirom na geografsko područje i klimatske uvjete. U određenoj mjeri, prisutnost manjih količina fuzarijskih mikotoksina u žitaricama i srodnim prehrambenim proizvodima je neizbježna, te je od velikog značaja za zaštitu javnog zdravlja uspostava smjernica i odredbi zakonodavstva i procjena rizika na nivou svake zemlje. U cilju sprječavanja onečišćenja te štetnih posljedica po zdravlje ljudi i životinja, kao i ekonomskih gubitaka u prehrambenoj i stočarskoj industriji, vrlo je značajna primjena prikladnih preventivnih mjera. Ukoliko ipak dođe do značajnijeg onečišćenja, potrebna je primjena učinkovitih metoda redukcije odnosno dekontaminacije, uz sustavnu kontrolu razine fuzarijskih mikotoksina i primjenu suvremenih analitičkih metoda u njihovoj detekciji.