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In the present work, the effect of high pressure processing (HPP) (0, 100, 200 and 300 MPa) and different treatment time (5 and 10 minutes) on the moisture uptake, cooking yield, colour and texture, as well as microbial population of chicken breast fillets was investigated. The application of high hydrostatic pressure resulted in a modification of quality parameters of chicken breast meat. By increasing pressure and time of the treatment the moisture uptake was reduced: samples treated with 300 MPa for 10 min had the lowest moisture uptake values. Cooking yield was not affected by HPP treatments. Increased pressure affected the colour by increasing L*, a* and b* values (only HPP treatment of 100 MPa in duration of 5 and 10 minutes did not affect colour of chicken breast meat). Lower pressures (100 and 200 MPa) tenderized, whereas elevated pressure (300 MPa) increased hardness in chicken breast fillets. Higher level of pressure (300 MPa) reduced bacteria count by about 3.0 – 5.3 log (CFU/g), depending on the microorganism and duration of the process.

Electrotechnologies gained increased popularity as non-thermal processing of foods as they offer many advantages over conventional thermal processing. These technologies effectively inactivate microorganisms, enhance the processing efficacy at lower treatment intensity (e.g. pressing, pre-treatment for drying, extraction etc.) with preservation of nutritional, functional and sensory characteristics of processed foods. Moreover, these technologies can be applied for targeted and controlled enzymatic treatments. Structural and conformational changes under these treatments may influence enzymatic inactivation, but also activate enzymes or enhance their activity. Therefore, the enzyme characteristics and treatment conditions could be finely tuned toward desirable properties and effects in food production and processing.

During ripening, the surface of dry traditional meat products (TMPs) becomes overgrown by fungi of the Penicillium spp., Aspergillus spp. and Eurotium spp. whose spores mostly come from the environment in which the ripening chambers are placed. Certain fungi species is often responsible for the occurrence of toxic compounds termed the mycotoxins, among which of the outermost importance in connection with meat products are aflatoxin B1 (AFB1) and ochratoxin A (OTA). Besides, some other mycotoxins such as citrinin (CIT), cyclopiazonic acid (CPA) and sterigmatocystin (STC) can also be present, but their impact on the quality and safety of meat products, and therefore also on human health, has still not been fully clarified. As control and prevention of toxicogenic fungi growth are key factors to the prevention of mycotoxin presence in dry-cured TMPs, levels of mycotoxin contamination, mycotoxin-producing mould species and factors of relevance for mycotoxin production, such as climate, should be determined.

Documented cases of mycotoxin occurrence in meat products call for further research into potential contamination sources, especially given an ever more increasing consumption of these nutritionally rich products. These foodstuffs can be contaminated with mycotoxins through three pathways: contaminated spices and other raw materials, mycotoxin-producing moulds present on the surface of dry-cured meat products, and carry-over effect from farm animals exposed to contaminated feed. In order to establish meat products’ mycotoxin contamination more precisely, the concentrations of all mycotoxins of relevance for these products should be determined. This manuscript reviews data on major mycotoxins present in different types of meat products, and discusses the contamination pathways, contamination levels and control & preventative measures.

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.

The aim of this study was to estimate a level of citric and tartaric acids in fruit nectars (n = 17) and juices (n = 13) available on the Croatian market. For analysis reverse-phase HPLC with UV/Vis detector set at 214 nm was used. Mobile phase was phosphate buffer (50 mM, pH = 2.80) at flow rate 0.5 mL min–1. The method was linear (r2 = 0.9999). LoD was 0.01 g L–1, LoQ was 0.03 g L–1 and the intra-day along with the inter-day variability were up to 3 %. The level of citric and tartaric acids in fruit nectars ranged from 1.26 to 4.42 g L–1 and 0.68 to 0.86 g L–1, respectively, and in fruit juices ranged from 3.03 to 7.67 g L–1 and 3.09 to 4.68 g L–1, respectively. A higher level of citric acid in fruit juices than in fruit nectars was detected (p < 0.05; MannWhitney U test). Six fruit juices contained a higher level of citric acid allowed by EU regulation implying the importance of monitoring concentrations of both acids in food products. This work is licensed under a Creative Commons Attribution 4.0 International License.

The aroma of a cheese is one of the key quality parameters and signs of distinguishing certain cheese types by consumers. Therefore, the aim of this paper is review the existing knowledge of the aromatic profile of cheeses ripening in an animal skin. Cheeses that ripen in an animal skin and produced in similar technology in Croatia (mišina cheese in a sack), in Bosnia and Herzegovina (Cheese in a sack (local name: mjeh), Montenegro (Cheese in a sack (local name: mjeh), Turkey (Tulum cheese), Lebanon (Darfiyeh cheese) and eastern Algeria (Bouhezza cheese). The specific characteristic of these cheeses is ripening in an animal skin, as in a sack (of ewe or goat). The aromatic profile of these cheeses has not been sufficiently investigated and has been conducted primarily on Tulum and to a smaller extent of Lebanese Darfiyeh cheese, and cheese in a sack. There is no data about other cheeses that ripen in an animal skin. Since very little research has been made on the aromatic profile of these cheeses, further research should be conducted., Aroma sira jedan je od ključnih parametara kvalitete i znakova raspoznavanja pojedine vrste sira od strane potrošača. Stoga je cilj ovog rada pregled postojećeg znanja o aromatskom profilu sireva, koji se proizvode na tradicionalan način i zriju u životinjskoj koži. Sirevi, koji zriju u životinjskoj koži i imaju sličnu tehnologiju, proizvode se u Hrvatskoj (Sir iz mišine), na području Bosne i Hercegovine (Sir iz mijeha), Crne Gore (Sir iz mijeha), Turske (Tulum sir), Libanona (Darfiyeh) i istočnog Alžira (Bouhezza sir). Specifičnost ovih sireva je zrenje u životinjskoj koži, odnosno mišini (ovčjoj, kozjoj). Aromatski profil navedenih sireva je slabo istražen, a istraživanja su najvećim dijelom provedena na Tulum siru i manjim dijelom na libanonskom Darfiyeh siru, siru iz mišine, dok za ostale sireve,koji zriju u životinjskoj koži nema nikakvih podataka. Obzirom da je vrlo malo istraživanja o aromatskom profilu ovih sireva do sada napravljeno, potrebno je provoditi daljnja istraživanja u ovom pravcu.

SUMMARY Lactobacillus plantarum O1 was isolated from the gut of sea bream (Sparus aurata) and identified with the API biochemical test and MALDI-TOF MS. This strain was further characterised according to the selection criteria for lactic acid bacteria as starter cultures for aquatic food production. L. plantarum O1 showed good antimicrobial activity against pathogenic test microorganisms. Further investigation confirmed it as the producer of the bacteriocin plantaricin. This strain also showed good growth at a wide range of temperatures (from 4 to 45 °C) and a wide range of pH (2–12), even in the presence of 3.5% NaCl. Its viability was also good after lyophilisation and in simulated gastric and small intestinal juice. The strain is a promising probiotic, and our further research will focus on its application in the biopreservation of fresh fish and shellfish.

This study focused on monitoring changes in aflatoxin M1 (AFM1) concentrations during produc- tion and storage of different fermented milks using selected probiotic and nonprobiotic combined cultures. Milk samples intended for fermentation were intentionally contaminated by adding a stan- dard of AFM1. All of the tested cultures caused remarkable reductions in AFM1 concentrations during the fermentation process. Probiotic cultures were more effective than nonprobiotic cultures, with Lactobacillus casei LC-01 strain being the most efficient, achieving a reduction level of approximately 58%. Among the nonprobiotic cultures, yoghurt culture YC- 380 was the most effi- cient, with a reduction level of approximately 41%.

The aim of this study was to investigate into the occurrence of deoxynivalenol (DON) and zearalenone (ZEN) in unprocessed cereals and soybean sampled in 2014 and 2015 from different fields located in Croatian regions. A total of 306 samples were analyzed for DON and 415 samples for ZEN concentrations using quantitative ELISA methods. In 2014, DON and ZEN were determined in all samples in the mean concentrations of 1, 461 ± 2, 265 µg/kg and 656 ± 853 µg/kg, respectively, while in 2015 these means were 2, 687 ± 2, 731 µg/kg and 1, 140 ± 1, 630 µg/kg, respectively. The cultivation year significantly (p < 0.05) influenced mycotoxin concentrations, whereas the influence of cultivation region was seen with ZEN for all cereals except soybean, and not seen with DON at all. A higher contamination determined during 2015 could be explained by high to extreme humidity evidenced in the period of cereals’ growth and harvesting.

Toxicity of gamma irradiated mycotoxins aflatoxin B1 (AFB1) and ochratoxin A (OTA) was investigated in vitro. AFB1 and OTA stock solutions (50 mM, in methanol) were gamma irradiated (5 and 10 kGy) and non-irradiated and irradiated mycotoxins solutions were tested for cytotoxicity on Pk15, HepG2 and SH-SY5Y cell lines (MTT assay, 1–500 lM concentration range ; 24 h exposure). Degradation of mycotoxin molecules was examined by liquid chromatography tandem mass spectrometry (HPLC-MS/MS). AFB1 and OTA radiolytic products were less toxic than the parent mycotoxins to all of the tested cell lines. Gamma irradiation even at 5 kGy had effect on AFB1 and OTA molecules however, this effect was dependent on chemical structure of mycotoxin. Since gamma irradiation at low dose reduced initial level of both mycotoxins, and gamma irradiated mycotoxins had lower toxicity in comparison to non-irradiated mycotoxins, it can be concluded that gamma irradiation could be used as decontamination method.

Mycotoxins represent secondary fungal metabolites not essential to the normal growth and reproduction of a fungus, but capable of causing biochemical, physiological and pathological changes in many species. Harmful effects of mycotoxins observed in humans and animals include carcinogenicity, teratogenicity, immune toxicity, neurotoxicity, hepatotoxicity, nephrotoxicity, reproductive and developmental toxicity, indigestion and so forth. These substances can be found in a variety of very important agricultural and food products, primarily dependent of product moisture content, and its water activity, relative air humidity, temperature, pH value, composition of the food matrix, the degree of its physical damage, and the presence of mold spores. Given that industrial processing has no significant effect on their reduction and in order to be able to vouch for the absence of mycotoxins, it is necessary to process foodstuffs under standardized and well-controlled conditions and to control each and every loop of the food production and storage chain. Preventative measures capable of reducing the contamination to the minimum must be in place and should be exercised by all means. In case that contamination does happen, methods for mycotoxin reduction or elimination should be implemented in dependence on a number of parameters such as properties of food or feed. Further research is needed in order to identify conditions that facilitate the growth of mycotoxin-producing fungi and develop effective preventative measures that can reduce contamination of food and feed as also to recognize possible synergistic effects of different mycotoxins in organism.

Traditionally, equid 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 possesses great potential for probiotic bacteria isolation. The aim of this study was to assess the probiotic potential of Lactobacillus plantarum M2 and L. plantarum KO9 isolated from donkey and mare milk, respectively, and determine TNF-α suppression attributed to their extracellular metabolites in lipopolysaccharide- (LPS-)stimulated human peripheral blood mononuclear cells (PBMCs). Resistance to simulated gastric and intestinal conditions, antimicrobial activity against pathogens, autoaggregation, coaggregation, biofilm quantification, antioxidative potential and haemolytic activity were determined. The isolated strains demonstrated great probiotic potential and their extracellular metabolites with molecular mass smaller than 2000 Da supressed TNF-α production up to 67% in LPS-stimulated PBMCs exerting high anti-inflammatory activity. Extracellular metabolites did not show any cyto/genotoxic effects toward PBMCs.

The aim of this study was to investigate the occurrence of citrinin in different cereals (n = 341) and feedstuffs (n = 67) coming from farms and feed factories established in Croatia and Bosnia & Herzegovina. The highest mean citrinin concentration (103 ± 102 µg/kg) was observed in cereals sampled in Bosnia & Herzegovina during 2014, although significantly different levels between the two countries were not observed. Across the cereal samples, the maximal citrinin concentration was determined in wheat (429 µg/kg), while across the feedstuffs, the highest concentration was found in pig feed (63 µg/kg). Despite of the increased citrinin levels found in some samples, especially wheat, the obtained values cannot be compared against the maximum limits, since no such levels are stipulated under the applicable legislation. But, given that data on citrinin are very scarce, they can serve as an indicator of cereal and feed contamination in this part of Europe.

As in the traditional production of cheese in lambskin sacks raw cow’s or sheep’s milk is mostly used, the purpose of this study is to see how the production affects the microbiological quality of the cheese. To do that, we tested 39 samples of raw cow’s and sheep’s milk, curd, ripened cheese (15, 30 and 45 days) and lambskin sacks for native microbial population. Two-thirds of the milk, curd and cheese samples had higher counts of staphylococci and enterobacteria than permitted by regulations. Not a single sample had Salmonella and Listeria monocytogenes, but we did find Escherichia coli in sheep’s milk and cheese, and yeast and mould in both types of milk and cheese. Staphylococcus xylosus prevailed in lambskin sacks. Despite the high incidence of S. aureus, even in the final product, staphylococcal enterotoxin was detected in only two sheep’s cheese samples. Among the lactic acid bacteria, Lactococcus lactis and Lactobacillus paracasei prevailed in cow’s cheese, whereas Leuconostoc mesenteroides and Lactobacillus plantarum prevailed in sheep’s cheese. In the lambskin sacks Leuconostoc mesenteroides and Lactobacillus plantarum were predominant. Our findings give an important insight into the fermentation and microbial ecology of the cheese in lambskin sacks.

In order to minimise human exposure to aflatoxin M1 (AFM1) the levels of this highly carcinogenic mycotoxin in milk, heat-treated milk, and other dairy products have been limited to -1. However, its removal from dairy products presents a challenge for dairy producers, as commercial additives change organoleptic properties, and filtration alone yields poor results. The aim of this study was to find a strain of lactic acid bacteria (LAB) from milk or dairy products that most effectively binds AFM1 and to see whether heat treatment of the selected LAB affects the binding efficiency. We also wanted to investigate whether centrifugation can improve filtering of the obtained AFM1-LAB complexes from milk. To do that, we isolated and identified 10 native LAB species/strains, incubated their viable or heat-treated cells (108 CFU mL-1) in milk spiked with 0.5 μg L-1of AFM1 at 4 °C for 0, 2, 4, and 24 h, and quantified the amount of unbound AFM1 with HPLC. AFM1 binding efficiency ranged from 21 to 92 % for viable cells and from 26 to 94 % for the heattreated ones. Since both viable and heat-treated Lactobacillus plantarum KM showed the best results, we used it for the next step in AFM1 removal from milk. Heat treatment in combination with filtration and centrifugation yielded removal as high as 96 %.

The aim of this study was to investigate ochratoxin A (OTA) and citrinin (CIT) co- occurrence in different unprocessed cereals (n=189) originating from Croatia during a three- year investigation period (2014-2016) using validated enzyme immunoassay (ELISA) methods. CIT and OTA were determined in 49% and 7% of samples, respectively. Significantly higher (p < 0.05) overall mean concentrations were determined for CIT (66.8 ± 76.0 µg/kg) in comparison to OTA (5.2 ± 1.1 µg/kg). Based on the analysis of all investigated cereals, CIT was found about 15 times more frequently than OTA and in similarly (15-fold) higher concentrations, irrespective of the cultivation year. The results revealed a moderately positive correlation between OTA and CIT concentrations in maize (rs = 0.44) and wheat (rs = 0.59), whereas in barley and oat this correlation (p > 0.01) was not significant.

Natural deep eutectic solvents (NADES) are a new generation of green solvents. They are mixtures of two or three compounds such as choline chloride as a cationic salt and alcohols, acids, amides, amines or sugars as hydrogen-bond donors. Although the majority of NADES’ components are of natural origin and therefore NADES are often presumed to be non- toxic, the evaluation of their toxicity and biodegradability must accompany the research on their synthesis and application. Therefore, the aim of this work was to investigate the effect of ten synthesised NADES towards bacteria (i.e., Escherichia coli, Proteus mirabilis, Salmonella typhimurium, Pseudomonas aeruginosa, Staphylococcus aureus), yeast (i.e., Candida albicans) and human cell lines (i.e., HeLa, MCF-7 and HEK293T). In addition, oxygen radical absorbance capacity (ORAC) method was used to determine the antioxidative activity of the tested NADES. Differences in toxicity response between microorganisms and cell lines were observed, and only NADES that contained organic acid showed toxicity towards the test systems. Furthermore, the NADES containing compounds that possess antioxidative activity also showed antioxidative activity. However, research whose primary purpose is the synthesis and application of NADES must be followed by an evaluation of their biological properties (e.g., antimicrobial activity, toxicity towards animal cells and antioxidative or other biological activity) to find the solvent with the best profile for wider industrial applications.

In this paper the effect of aflatoxin B1, ochratoxin A and zearalenon on morphology, growth parameters and metabolic activity of yeasts Saccharomyces cerevisiae, Saccharomyces uvarum, Candida utilis and Kluyveromyces marxianus was determined. The results showed that the three mycotoxins affected the morphology of all these yeasts, primarily the cell diameter, but not their final cell count. Fourier transform infrared spectroscopy showed that the yeast membranes bound the mycotoxins, C. utilis in particular. The cell membranes of most yeasts underwent denaturation, except S. uvarum exposed to ochratoxin A and zearalenone. In the early stage of fermentation, all mycotoxin-exposed yeasts had lower metabolic activity and biomass growth than controls, but fermentation products and biomass concentrations reached the control levels by the end of the fermentation, except for C. utilis exposed to 20 μg/mL of zearalenone. The adaptive response to mycotoxins suggests that certain yeasts could be used to control mycotoxin concentrations in the production of fermented food and beverages.

Mycotoxin patulin is one of the quality indicators for apple juice. Like other mycotoxins, it raises consumer health concerns. The issue of low quality is particularly relevant for apples provided by small producers, whose quality control may not be standardised. As sulphur dioxide (SO2) is common in fruit preservation against fungi, the aim of this study was to determine how efficient it is in degrading patulin in apple juices stored in real-life conditions. This included refrigerated (4 °C) and non-refrigerated warehouses/environments (30 °C) over 8, 10, 12, and 20 weeks of storage. Apple juice was diluted to 0.010 μg g-1, 0.050 μg g-1, and 0.100 μg g-1 of patulin. SO2 was added to each sample in the amounts of 250 μg mL-1 and 50 μg mL-1. Untreated juice samples for each patulin concentration served as controls under the same experimental conditions. Patulin content was determined with high performance liquid chromatography. The best degradation was observed with 250 μg mL-1 of SO2 at 30 °C regardless of the patulin baseline concentration. Although treatment with SO2 and refrigeration did not fully remove patulin, it was highly efficient over twelve weeks of storage. Our results suggest that patulin levels can be reduced between 33 and 100 % at 30 °C and up to 100 % at 4 °C., Mikotoksin patulin jedan je od pokazatelja kakvoće jabučnog soka. Poput drugih mikotoksina, prisutnost patulina predstavlja zdravstveni problem. Pitanje loše kakvoće jabuka odnosi se na mala obiteljska gospodarstva, gdje se kakvoća korištenih jabuka ne može standardizirati. Prisutnost plijesni i mikotoksina zdravstveni je problem, a SO2 pospješuje razgradnju patulina. Svrha ove studije bila je odrediti razgradnja patulina u jabučnom soku tretiranim sa SO2 pri različitim temperaturama skladištenja. Utjecaj SO2 na razgradnju patulina ispitivana je u uzorcima pohranjenima u svakodnevnim uvjetima. To uključuje hladnjak (4 °C) i nehlađena skladišta/okoliš (30 °C) tijekom 8, 10, 12 i 20 tjedana. Jabučni sok razrijeđen je na koncentracije 0,010 μg g-1, 0,050 μg g-1 i 0,100 μg g-1 patulina. U svaki uzorak dodan je SO2 u količini od 250 μg mL-1 i 50 μg mL-1. Uzorci soka u koji nije dodan SO2 za svaku koncentracijsku razinu patulina poslužili su kao kontrola i bili su pod istim eksperimentalnim uvjetima. Patulin u uzorcima određivan je pomoću tekućinskog kromatografa visoke djelotvornosti (HPLC). Najveća razgradnja patulina zabilježena je u termostatskim uvjetima s koncentracijom SO2 od 250 μg mL-1, bez obzira na koncentraciju patulina kontrolnog uzorka. Iako hlađeni uvjeti i dodatak SO2 nisu potpuno uklonili patulin iz uzoraka, nakon dvanaest tjedana skladištenja uočena je visoka učinkovitost razgradnje. Rezultati pokazuju da se razine patulina mogu smanjiti 33-100 % pri temperaturi od 30 °C i 0-100 % pri 4 °C.

In this study, the levels of aflatoxin B1 (AFB1), ochratoxin A (OTA), zearalenone (ZEN), deoxynivalenol (DON) and fumonisins (FUM) in unprocessed cereals (n = 189) and cereal-based products (n = 61) were determined using validated ELISA methods. All samples originated from either conventional or organic production corresponded to the 2015 harvest in Croatia. Based on the mean mycotoxin concentrations, the risk for the consumer to exceed the tolerable daily intake (TDI) for these toxins by the consumption of both types of cereals and cereal-based products was assessed. Mycotoxin contamination of organic cereals and organic cereal-based products was not significantly different (p > 0.05). Given that the exposure assessment resulted in a small fraction of the TDI (maximum: DON, 12% of TDI), the levels of the investigated mycotoxins in both types of cereals and cereal-based products from the 2015 harvest did not pose a human health hazard.

In this study, the effect of an isolated and well-characterized autochthonous starter culture (ASC), various sugars (glucose and maltodextrin, w = 0.8 %) and different fermentation temperatures (12 and 20 oC) on fermentation and quality of Slavonian Kulen produced using the traditional technology and recipe were investigated. Physicochemical and microbiological analyses were carried out after 20 days of fermentation. Upon the completion of the production process (90 days), a sensory analysis was carried out, too. Furthermore, pH valuewas continuously measured throughout the twenty-day fermentation period. The addition of an ASC and sugars and fermentation temperature variations significantly (P < 0.05) affected the instrumental colour and texture parameters of the Slavonian Kulen. The fermentation process was most intense in the samples supplemented with an ASC and 0.8 % - glucose and fermented at 20 °C. Microbiological analysis showed samples supplemented with an ASC and fermented at higher temperatures to contain a higher number of lactic acid bacteria (LABs) and coagulase- negative staphylococci (CNS) and to be safe. Sensorial evaluation confirmed the outcomes of physicochemical and microbiological analyses and showed differences between samples fermented at different temperatures and supplemented with sugars and an autochthonous starter culture.

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 from apple, blueberry and 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 60 °C), 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), except in apple juice, where statistical significant (p < 0.05) influence of quadratic interaction of amplitude on bacteria reduction were observed. In all samples of fruit juices and nectars in terms of ultrasonic treatment at 60 °C and times of 3, 6 and 9 min, regardless of the value of the amplitude, complete inactivation of the growth of yeasts and moulds were achieved, while at 20 and 40 °C it is not observed. 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 min ranged from 3.556 to 5.934 log units, depending on the initial number of selected yeasts and moulds before treatment.

When domestic animals are exposed to mycotoxins, significant amounts of the latter shall be carried over into animal products such as milk, eggs and meat. This study was carried out in order to determine the possible presence of aflatoxin B1 (AFB1), ochratoxin A (OTA) and citrinin (CIT) in game sausages (n = 15), semi-dry sausages (n = 25) and fermented dry-meat products (n = 50), randomly taken from individual producers and the Croatian market. AFB1 and OTA were quantified using ELISA, while CIT was quantified using HPLC-fluorescence detector. Out of 90 samples, the fungi most frequently isolated from dry-cured meat products were of Penicillium species, while Aspergillus was isolated from only one sample. As much as 68.88% of the samples were positive for mycotoxins. Finally, the analysis of different types of meat products resulted in OTA identification in 64.44%, CIT identification in 4.44% and AFB1 identification in 10% of the samples. The maximum OTA concentrations established in the commercial sausage samples equalled to 7.83 μg/kg, while that of AFB1 amounted to 3.0 μg/kg. Generally, although OTA was detected in all three types of products in different percentage shares, mutual differences were not statistically significant (P > 0.05).

The microbiological quality of a hard mountain unpasteurised sheep cheese from three randomly selected manufacturing locations in Kosovo was investigated. Forty-eight samples of row milk, coagulum, 8–10 days ripening cheese and of ready to eat cheese (45-days in brine) were tested. Seventy-five per cent of raw milk samples failed to comply with EU regulation 853/2004. All of coagulum and ripened cheese failed to comply with EU regulation 2073/2005 on process hygiene criteria. Despite the high incidence of coagulase-positive staphylococci even in the final product [>105 colony-forming units (cfu)/g], Staphylococcal enterotoxin was detected in none of the samples and no samples were positive for Listeria monocytogenes and Salmonella enteritidis.

Fungicides are the most common agents used in postharvest treatment of fruit and are the most effective against blue mould, primarily caused by Penicillium expansum. Alternatively, blue mould can be treated with antagonistic microorganisms naturally occurring on fruit, such as the bacterium Gluconobacter oxydans. The aim of this study was to establish the antifungal potential of the G. oxydans 1J strain isolated from apple surface against Penicillium expansum in culture and apple juice and to compare it with the efficiency of a reference strain G. oxydans ATCC 621H. The highest antifungal activity of G. oxydans 1J was observed between days 3 and 9 with no colony growth, while on day 12, P. expansum colony diameter was reduced to 42.3 % of the control diameter. Although G. oxydans 1J did not fully inhibit mould growth, it showed a high level of efficiency and completely prevented patulin accumulation in apple juice.

The aim of this study was to determine the effects of the essential oil of Thymus serpyllum L. and of its components thymol and total phenols (total phenolic content, TPC) extracted from the plant on the growth and mycotoxin production of Aspergillus ochraceus, A. carbonarius, and A. niger. Minimal inhibitory concentration (MIC) determined for the essential oil and thymol, and selected concentration of the TPC extract inhibited fungal growth and ochratoxin A biosynthesis by more than 60 %, depending on the conditions and duration of incubation with the fungi. Essential oil showed the strongest inhibitory effect which may have been related to the synergistic or cumulative effects of its components

In this study, the basic chemical and fatty acid compositions of autochthonous Croatian cow and sheep cheeses in a lamb skin sack (local name: ‘‘sir iz mišine’’) were determined. Also, the influences of ripening period and different starter cultures on chemical and fatty acid composition of these cheeses were investigated. Samples of cow (n = 20) and sheep (n = 20) milk cheeses were produced in three different ways: from raw milk without the addition of a starter culture, from pasteurized milk with commercial starter cultures and with previously isolated autochthonous starter cultures (Lactococcus lactis S1 or Lactobacillus plantarum B or a mixture of both). Samples were taken during a 45-day ripening period (on days 0, 15, 30 and 45). The ripening time significantly affected all basic chemical parameters, while different starter cultures significantly (p < 0.05) influenced protein, fat and ash content. Ripening time had no significant effect on the representation of the investigated fatty acid groups (p > 0.05), but a significant difference was found depending on the starter cultures used and the type of cheese analysed, in terms of statistically higher proportion (p < 0.05) of polyunsaturated fatty acids in the finished sheep’s milk cheese (2.58–2.97%) in comparison to the cow’s milk cheese (1.93–2.14%). Fatty acids most represented in the analysed cheeses were palmitic, oleic and stearic acid.

Conventional methods for the identification of Listeria in foodstuffs are generally cumbersome and time consuming. The use of primary enrichment in half strength Fraser broth and the use of PALCAM agar were assessed in comparison with API Listeria and polymerase chain reaction (PCR) for their ability to accurately detect and confirm the presence of List. monocytogenes in milk products. The aim of our work was to detect List. monocytogenes in domestic unpasteurised milk, fresh cheese and cream of raw milk taken from four different district of Zagreb-Croatia using conventional (microbiological and biochemical – API test) and PCR methods. Of the 180 milk products samples tested, 27·6% were presumptively positive for Listeria on PALCAM agar. Only 21·3% of samples were confirmed to be positive for Listeria by API Listeria test, and 17·3% were confirmed to be positive for List. monocytogenes by PCR amplification of the hly gene (64 bp). PCR was able to eliminate the false positive and detect all List. monocytogenes in the milk products, unlike the conventional methods used in the industry. These results indicate a low presence of this pathogen in this area (Zagreb) of Croatia. PCR proves to be a sensitive and rapid technique to be included in the procedure of detection of List. monocytogenes in food products and this method is considerably faster than current standard methods.

The aim of this study was to investigate the efficiency of gamma (γ) irradiation in the reduction of ochratoxin A (OTA) present in dry- cured meat products prepared from intentionally contaminated raw materials from OTA-treated pigs. OTA concentrations determined in the samples (n=24) ranged from 25.85 μg/kg in bacon to 17.81 μg/kg in smoked ham. After γ-irradiation at doses of 3, 7 and 10 kGy (i.e. the doses used in the food industry), a dose-depended OTA reduction was observed, however not statistically significant. The mean OTA reduction achieved with 3-kGy, 7-kGy and 10-kGy γ-doses approximated to 8.51%, 13.89% and 22.48%, respectively. The storage of irradiated samples (one month, +4°C) did not significantly affect OTA levels. Based on the correlation between the OTA reduction level and basic chemical composition of dry-cured meat samples, OTA reduction may be linked to the samples’ fat content. The obtained results indicate that γ- irradiation can reduce OTA levels in dry-cured meat products, but only to a limited extent due to the complexity of their matrix.

Detailed investigation on the effect of gamma (γ) irradiation on germination, sporulation, and growth of aflatoxigenic moulds ( Aspergillus parasiticus 2999, Aspergillus flavus 305, and Aspergillus niger 388), as well as on the reduction of aflatoxin B 1 (AFB 1 ) level in artificially and naturally contaminated maize/feed samples was performed. The results of in vitro and in situ experiments with aflatoxigenic moulds demonstrated that 5 kGy-γ irradiation manages to prevent sporulation, germination and growth of the tested moulds both when in form of a pure and when in form of a mixed culture. In the feed samples artificially contaminated with AFB 1 (50 μg kg −1 ) 5 kGy-γ irradiation reduced AFB 1 level by around 60%, while 10 kGy-dose reduce it for around 85%. Similarly, in feed samples spiked with AFB 1 in the concentrations of 100 μg kg −1 5 kGy-dose reduced the AFB 1 level by approximately 70%, while the dose of 10 kGy reduced it by approximately 90%. The experiments on naturally contaminated maize samples (n = 30) confirmed these observations; following a 5 kGy-irradiation, the overall mean AFB 1 reduction equalled to 69.8%, while the irradiation with a 10 kGy-dose achieved the overall mean toxin reduction of 94.5%. The obtained results indicate that γ irradiation can be used to prevent the growth of aflatoxigenic moulds and to reduce the AFB 1 levels in various goods intended for animal and human consumption, thus minimizing the animal and human exposure to this carcinogenic mycotoxin.

The study focuses on developing novel cottage 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.

The aim of this study was to investigate the possibilities of ochratoxin A (OTA) reduction in home-made meat products. Meat sausages (n = 50) produced from raw materials coming from pigs exposed to OTA-contaminated feed, were subject to common heat processes practiced in households (cooking, frying and baking). Concentrations of OTA in pre- and post-processed products were quantified using a validated immunoassay method, enzyme-linked immunosorbent assay, and confirmed using a high-performance liquid chromatography with fluorescence detection. In line with the differences in recipes used and the degree of OTA accumulation in raw materials, OTA concentrations established in Mediterranean and roast sausages were lower than those found in liver and blood sausages. Baking of contaminated sausages at the temperatures of 190-220°C (for 60 min) resulted in significant reduction of OTA levels (75.8%), while 30-min cooking (at 100°C) and frying (at 170°C) proved to be significantly less effective (e.g. yielding OTA reductions of 7.4% and 12.6%, respectively). The results pointed out that despite high OTA stability, heat processes are capable of reducing its concentration in home-made meat products, depending on the processing modality used.

Svrha je ovoga istraživanja bila identificirati i okarakterizirati potencijalne autohtone funkcionalne starter kulture izolirane iz domaće kobasice proizvedene od konjskog mesa. Dominantnu su mikrofloru u uzorcima kobasica činile bakterije mliječne kiseline (BMK), a zatim mikrokoki. Od bakterija mliječne kiseline prevladavale su vrste Lactococcus lactis ssp. lactis i Lactobacillus plantarum. Vrsta Lactococcus lactis ssp. lactis nije uobičajena u fermentiranim kobasicama, pa smo ju okarakterizirali kao potencijalnu funkcionalnu starter kulturu. Vrsta Lactococcus lactis ssp. lactis proizvela je značajnu količinu mliječne kiseline, a uspješno je rasla pri 12, 18 i 22 ºC, te u prisutnosti 5 % NaCl. Također je dobro podnijela liofilizaciju i simulirane uvjete želučanog soka i soka tankog crijeva. Osim toga, uspješno je suzbila rast patogena i pokazala je dobra adhezijska svojstva in vitro., The aim of this study is to identify and characterise potential autochthonous functional starter cultures in homemade horsemeat sausage. The dominant microflora in the samples of horsemeat sausage were lactic acid bacteria (LAB), followed by micrococci. Among the LAB, Lactococcus lactis ssp. lactis and Lactobacillus plantarum were the dominant species, and since the first is not common in fermented sausages, we characterised it as a potential functional starter culture. Lactococcus lactis ssp. lactis produced a significant amount of lactic acid, displayed good growth capability at 12, 18 and 22 °C, growth in the presence of 5 % NaCl, good viability after lyophilisation and in simulated gastric and small intestinal juice, antimicrobial activity against test pathogens, and good adhesive properties in vitro.

Fusarium mycotoxins are frequent contaminants of cereals in this part of Europe. In this study, a total of 181 samples of maize, wheat, barley and oat were collected from different fields situated in six Croatian regions, and analysed using a validated ELISA method. Concentrations of deoxynivalenol (DON), zearalenone (ZEA), fumonisin (FUM) and T-2 toxin (T-2) were determined. Methodology validation showed the mean recovery rates to range from 72.8% to 103.6%, with the intermediate precision of 70.699.4% and variation coefficients (CV) of 3.6–6.2% and 6.1–10.2%, respectively. Maize proved itself as the most contaminated cereal, with DON as the most represented Fusarium mycotoxin (52.5%) followed by ZEA (40.5%), FUM (37.5%) and T-2 toxin (33%). Mycotoxin concentrations higher than allowed were observed in 4 maize samples and a single wheat sample. Given the warm and dry study period, such a contamination might be associated with some factors other than climate conditions that could cause Fusarium mycotoxin formation. The obtained data pointed towards the necessity for a consistent control over these contaminants and the definition of their maximal allowed levels in different foodstuffs and feedstuffs.

Biodegradation of Olive Mill Wastewater by Trichosporon Cutaneum and Geotrichum CandidumOlive oil production generates large volumes of wastewater. These wastewaters are characterised by high chemical oxygen demand (COD), high content of microbial growth-inhibiting compounds such as phenolic compounds and tannins, and dark colour. The aim of this study was to investigate biodegradation of olive mill wastewater (OMW) by yeasts Trichosporon cutaneum and Geotrichum candidum. The yeast Trichosporon cutaneum was used because it has a high potential to biodegrade phenolic compounds and a wide range of toxic compounds. The yeast Geotrichum candidum was used to see how successful it is in biodegrading compounds that give the dark colour to the wastewater. Under aerobic conditions, Trichosporon cutaneum removed 88 % of COD and 64 % of phenolic compounds, while the dark colour remained. Geotrichum candidum grown in static conditions reduced COD and colour further by 77 % and 47 %, respectively. This investigation has shown that Trichosporon cutaneum under aerobic conditions and Geotrichum candidum under facultative anaerobic conditions could be used successfully in a two-step biodegradation process. Further investigation of OMW treatment by selected yeasts should contribute to better understanding of biodegradation and decolourisation and should include ecotoxicological evaluation of the treated OMW.

The microbial population of a traditional Croatian fermented sausage “Slavonski kulen” was isolated, identified and subjected to technological and functional characterization in order to select potential autochthonous functional starter cultures. Dominant microflora were lactic acid bacteria (LAB), followed by staphylococci. Identification of isolated lactobacilli showed domination of Leuconostoc mesenteroides and Lactobacillus acidophilus while Staphylococcus xylosus and Staphylococcus warneri outnumbered the staphylococcal microbiota. Most of the isolated LAB and Staphylococcus species displayed good growth in the presence of 5% of NaCl and at 12, 18 and 22 °C. All LAB and most of the staphylococci possess proteolytic activity and only Staphylococcus xylosus had lipolytic activity. All lactobacilli and staphylococci isolates produced significant concentrations of lactic acid (as determined by HPLC) and showed antimicrobial activity against pathogenic test microorganisms. Dominant LAB and Staphylococcus species displayed growth in the presence of 1% bile. Most of the staphylococci and all of lactobacilli showed sensitivity to all antibiotics tested.

Growth Inhibition of Aspergillus Ochraceus ZMPBF 318 and Penicillium Expansum ZMPBF 565 by Four Essential OilsFungi produce a large variety of extracellular proteins, organic acids, and other metabolites and can adapt to several environmental conditions. Mycotoxin-producing moulds of the genera Aspergillus and Penicillium are common food contaminants. One of the natural ways to protect food from mould contamination is to use essential oils. In this study, we evaluated the effect of essential oils of cinnamon, lavender, rosemary, and sage at 1 % (v/v) concentration in yeast media inoculated with spores (final concentration 106 mL-1 media) of Aspergillus ochraceus ZMPBF 318 and Penicillium expansum ZMPBF 565, alone or in combination, on fungal biomass. Cinnamon showed the best inhibitory effect (100 %). Lavender oil best inhibited the growth of Aspergillus ochraceus (nearly 100 %), and was less successful with Penicillium expansum (having dropped to 57 % on day 28). With cultivation time the inhibitory effect of sage and rosemary oil grew for Aspergillus ochraceus and dropped for Penicillium expansum.These results suggest that fungi can be controlled with essential oils, especially with cinnamon oil.