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The search for unexplored plant resources that would provide a good basis for the development of novel probiotic functional foods is rapidly increasing. In this context, the strawberry tree fruit ( Arbutus unedo L.) is particularly interesting, as it is rich in numerous antioxidant bioactive compounds that have been shown to be beneficial to health, but have not yet found industrial applications. In this work, the probiotic characterization of lactic acid bacteria strain Lactiplantibacillus plantarum DB2, isolated from strawberries ( Fragaria ananassa × Duch.), was performed. The tested strain proved to be safe to use, displaying no antibiotic resistance or hemolytic activity. Due to its proven probiotic potential during simulated gastrointestinal transit, its antimicrobial activity, and its coaggregation with pathogens, it was selected for fermentation of an aqueous Arbutus unedo L. extract, which was subsequently microencapsulated and freeze-dried to extend its shelf life and preserve its functional properties. The antioxidant activity of the ferment obtained was maintained (80%), while after microencapsulation and freeze-drying, about 50% and 20% of the antioxidant activity was retained, respectively. In conclusion, this study demonstrates for the first time the application of probiotics isolated from strawberries in the fermentation of strawberry tree extract and monitors the antioxidant activity during post-fermentation formulation, paving the way for a potential industrial application of this underutilized plant.

Climate change, especially in the form of temperature increase and sea acidification, poses a serious challenge to the sustainability of aquaculture and shellfish farming. In this context, lactic acid bacteria (LAB) of marine origin have attracted attention due to their ability to improve water quality, stimulate the growth and immunity of organisms, and reduce the impact of stress caused by environmental changes. Through a review of relevant research, this paper summarizes previous knowledge on this group of bacteria, their application as protective probiotic cultures in mollusks, and also highlights their potential in reducing the negative impacts of climate change during shellfish farming. Furthermore, opportunities for further research and implementation of LAB as a sustainable and effective solution for adapting mariculture to changing climate conditions were identified.

The aim of this paper was to examine the effect of different OTA concentrations on the parameters of oxidative stress (glutathione (GSH) and malondialdehyde (MDA) concentrations) and glucose utilization in ethanol production by wine yeasts. In addition to the above, artificial neural networks (ANN) were used to predict the effects of different OTA concentrations on the fermentation ability of yeasts and oxidative stress parameters. The obtained results indicate a negative influence of OTA (4 µg mL -1 ) on ethanol production after 12 h. For example, K. marxianus produced 1.320 mg mL -1 of ethanol, while in the control sample 1.603 µg mL -1 of ethanol was detected. However, after 24 h, OTA had no negative effect on ethanol production, since it was higher (7.490 and 3.845 mg mL -1 ) in comparison to control samples. Even low concentrations of OTA affect GSH concentrations, with the highest being detected after 12 and 24 h (up to 16.54 µM), while MDA concentrations are affected by higher OTA concentrations, with the highest being detected at 24 h (1.19 µM). The obtained results with the use of ANNs showed their potential for quantification purposes based on experimental data, while the results of ANN prediction models have shown to be useful for predictions of what outcomes different concentrations of OTA that were not part of experiment will have on the fermentation capacity and oxidative stress parameters of yeasts.

The use of probiotics in the diet of bivalves poses a great potential in aquaculture as an alternative to antibiotics. The aim of this study was to assess the effect of Lactiplantibacillus plantarum I on the phenolic content and antioxidant capacity (AC) of queen scallop extracts after one month of feeding. Total phenols (TP) ranged from 28.17 ± 3.11 to 58.58 ± 8.57 mg GAE/100 g, total non-flavonoids (TNF) from 23.33 ± 3.66 to 36.56 ± 9.91 mg GAE/100 g, and total flavonoids (TF) from 10.56 ± 5.57 to 30.16 ± 1.69 mg CE/100 g. AC was assessed via three different methods: the ferric-reducing ability of plasma assay (FRAP), 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic) acid assay (ABTS), and 2,2-diphenyl-1-picryhydrazyl assay (DPPH). FRAP values ranged from 0.13 ± 0.03 to 0.17 ± 0.02 µM AA/g, ABTS from 0.68 ± 0.11 to 2.79 ± 0.34 µM AA/g, and DPPH from 1.75 ± 0.17 to 2.98 ± 0.53 µM AA/g. Among all extracts, the best phenolic content and AC were observed in water extracts from queen scallops. The bivalves treated with the Lactiplantibacillus plantarum I-enriched diet showed higher AC according to the FRAP assay in all extracts. A significant correlation was observed between AC and TP and TNF in control and Lactiplantibacillus plantarum I-treated scallops.

Research Background: While it is clear that SARS CoV-2 coronavirus is the primary respiratory virus, there are no entirely clarified ways of transmission. Foodborne transmission has remained an unexplained path. Therefore, the goals of this paper are to examine and present an assessment of the most appropriate of the four selected kits for RNA extraction for the testing and detection of SARS-CoV-2 on food packaging surfaces, food surfaces, and in food. This will enable to indicate the possibility of infection through contact or direct food consumption., Experimental Approach: Finding the best technique is vital as RNA extraction is one of the essential elements in detecting SARS-CoV-2. This was achieved through an experiment with four commercial kits following the original manufacturers' protocols, and with a modification of the original protocols that included the use of ethanol and isopropanol. The selected kit was used for RNA extraction from the swabs of packaging surfaces, food surface, and ready-to-eat food samples. The coronavirus was then identified using real-time reverse transcription-polymerase chain reaction (RT-PCR) assays to determine whether the SARS-CoV-2 virus or viral particles are present in the food chain with the overall purpose of demonstrating the possibility that food can contribute as a vehicle for the transmission of the virus., Results and Conclusions: The findings of this investigation made the most effective extraction kit and protocol stand out. The results of the applicability of the kit indicated a significant share of positive samples of viral SARS-CoV-2 virus particles on surfaces from the environment where infected persons with 'silent' COVID-19 infection, with mild symptoms or no symptoms, were present. However, according to the findings of the second part of the study, the virus was not detected on the examined samples of food packaging surfaces, food surfaces, and food., Novelty and Scientific Contribution: The presented results distinguished one of the most suitable protocols for isolating RNA from environmental surface samples. The main contribution of the study is in the presentation of the results, that is, the examination of samples that are primarily related to the food chain, food packaging, food surfaces, and ready-to-eat food. The results of this study could also be helpful for further determination of the potential of food as a vector for the transmission of coronaviruses., Competing Interests: CONFLICT OF INTEREST The authors declare no conflict of interest.

3D printing technology (3DP) as additive manufacturing is an innovative design technology that can meet the individual nutritional and sensory needs of consumers. Therefore, the aim of this work was to apply 3DP in the production of a strawberry-based functional product with the addition of two hydrocolloids (corn and wheat starch) in three proportions (10, 15 and 20%) and to investigate the influence of 3DP process parameters on physico-chemical and textural properties, as well as the bioactive and antioxidant potential and microbiological stability, with(out) the addition of natural antimicrobial agents. Starch type had a significant effect on all tested bioactive compounds, as well as on starch content, except for total phenolic and hydroxycinnamic acid contents. Considering the content of bioactive compounds and antioxidant capacity, program 2 proved to be more suitable than program 1. All samples exhibited good textural properties, a high degree of stability and minimal geometric deviations. Regarding microbiological safety, no pathogenic bacteria were found in the 3DP samples during storage. The 3DP sample with added citral at a concentration of 75 mg L -1 showed the best microbiological quality. Ultimately, 3DP can be successfully used for the production of new strawberry-based functional products.

One of the ways to impact emerging problems of unhealthy diet such as microbiota dysbiosis, inflammation, and oxidative stress is the application of probiotics and their incorporation into different food matrices. Discovery and selection of appropriate probiotic bacteria is challenging procedure especially for fermented meat products that have also been described as a potential source of resilient probiotic microorganisms. The aim of this study was to investigate probiotic bacteria Lactiplantibacillus plantarum 1K isolated from traditional fermented meat product for its potential beneficial properties. Furthermore, small probiotic metabolites were extracted, and their anti-inflammatory activity was tested in a lipopolysaccharide-stimulated inflammatory model on human peripheral blood mononuclear cells (PBMCs). Safety characteristics of metabolites including cytotoxicity and genotoxicity were also determined. Investigated probiotic strain exerted high antioxidant potential by viable cells but also by metabolite fraction. Viable cells retained the satisfactory antioxidant activity after gastrointestinal transit. Extracted probiotic metabolites significantly inhibited TNF-α production in LPS-stimulated PBMC thus exerting anti-inflammatory activity. Metabolites alone showed no cytotoxic or genotoxic activity toward isolated immune cells. Obtained results indicate the possibility to use fermented meat products as sources for specific probiotics that might provide antioxidant and anti-inflammatory benefits for the consumers., (© The Author(s) 2022. Published by Oxford University Press on behalf of the UK Environmental Mutagen Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Aims: The literature highlights the pathology of inflammation and its role in carcinogenesis, ageing and related diseases. Inflammatory processes induce oxidative stress and reduce antioxidant capacity. This study investigated the antioxidant and anti-inflammatory potential of probiotic bacteria isolated from fermented whey under conditions of induced stress., Methods and Results: Functional antioxidant characterization of potential probiotic bacteria Lactiplantibacillus plantarum S1 was performed under different growth conditions (aerobic, respiratory and anaerobic) and under stress to find the conditions that yield the most effective cells. Since aerobic growth yielded the most potent cells, the free radical scavenging ability of live and heat-killed cells was measured before and after exposure to gastrointestinal conditions. For heat-killed cells and extracted probiotic metabolites, the reduction of DNA damage to immune cells was determined in the hydrogen peroxide exposure comet assay. The combination of inactivated cells and metabolites showed the best reduction in DNA damage. Finally, in the LPS inflammation model, the aforementioned probiotic metabolites significantly reduced Tumour necrosis factor-alpha levels in immune cells., Conclusions: Whey-derived potential probiotic bacteria exert antioxidant and anti-inflammatory effects, and based on this study, we propose a model combining inactivated cells and metabolites to reduce inflammatory and oxidative stress-related adverse effects., Significance and Impact of Study: In this study, a new probiotic model is proposed for continuous use to reduce oxidative and inflammatory stress in the gut., (© 2022 Society for Applied Microbiology.)

This study investigated the status of bioactive compounds (phenolic compounds, carotenoids, and vitamin C), changes in color performance, and microbiological quality in smoothies preserved by high-pressure processing (HP) and thermal pasteurization (P) during cold storage at 4 °C for 21 days. Chemometric tools were used to select relevant variables that represent the most useful information for the fast and accurate quality assessment of smoothies. HP was performed at 350 and 450 MPa for 5 and 15 min at room temperature, respectively, while P was performed at 85 °C for 7 min. Smoothies were prepared by blending juices of apple (50%, v / v ), carrot (20%, v / v ), chokeberry (5%, v / v ), Indian banana puree (10%, w / v ), and almond drink (15%, v / v ). The results obtained indicated that lower pressures with a shorter duration of HP showed higher levels of bioactive compounds in the smoothies, compared to the control samples. Compared to P, the HP samples exhibited a greater stability of bioactive compounds during shelf life. HP was found to be highly effective in reducing the native microflora of the smoothies, without subsequent microbial activation during storage. This study demonstrated the usefulness of the chemometric approach in interpreting complex datasets for the effective quality assessment of smoothies treated with different preservation technologies.

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., Competing Interests: CONFLICT OF INTEREST: The authors declare no conflict of interest.

Xerophilic species of Aspergillus, Penicillium and Eurotium genera from surfaces of dry-cured traditional meat products (TMPs) can cause mycotoxin contamination during uncontrolled household processing. The aim of this study was to investigate into surface moulds growing on Croatian prosciuttos and fermented sausages produced in different climate regions using different technologies (n = 160), and to relate the occurrence of aflatoxin B 1 (AFB 1 ) and ochratoxin A (OTA) to their presence. The results revealed the Penicillium (79%) to be the dominating contaminating mould, while Aspergillus (11%), Eurotium (7%) and Mucor (4%) species were present in a significantly lower number of isolates, with higher prevalence and greater diversity in prosciuttos than in sausages, relative of the production technology and regional climate. OTA contamination (14% of samples) was significantly more frequent than that with AFB 1 (8% of samples), with OTA concentration rising to the maximal 6.86 μg/kg, whereas AFB 1 concentrations were slightly higher than, or around, the limit of quantification of the method in use, with the maximal value of 1.92 μg/kg. The presence of AFB 1 in absence of toxicogenic moulds, observed in some samples, can be attributed to contaminated spices used in TMP production or an indirect contamination via a carry-over effect., (Copyright © 2019 Elsevier B.V. All rights reserved.)

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., (© 2019 Elsevier Inc. All rights reserved.)

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., Competing Interests: CONFLICT OF INTEREST: None to declare.

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 <0.05 μg kg-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 %.

In this paper the effect of aflatoxin B 1 , 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.

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.

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 (r s  = 0.44) and wheat (r s  = 0.59), whereas in barley and oat this correlation (p > 0.01) was not significant.

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 (20kHz) according to procedure set by central composite design (CCD). Three operational parameters, amplitude (60, 90 and 120μm), temperature (20, 40 and 60°C), and treatment time (3, 6 or 9min) 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 9min, 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 9min ranged from 3.556 to 5.934 log units, depending on the initial number of selected yeasts and moulds before treatment., (Copyright © 2017 Elsevier B.V. All rights reserved.)

The aim of this study was to investigate 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 analysed 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.

In this study, the levels of aflatoxin B 1 (AFB 1 ), 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.

The benefits of probiotic bacteria have been widely explored. However, fermented foods and digestive system of humans and animals are an inexhaustible source of new potentially probiotic microorganisms. In this study we present three new Lactobacillus plantarum strains isolated from different dairy products: cow's cheese, sheep's cheese and whey. In order to determine the antibacterial activity of yet unexplored L. plantarum strains against Salmonella enterica serotype Typhimurium, in vitro competition and co-culture tests were done. Furthermore, adhesion of these strains to Caco-2 cells and their influence on the adhesion of Salmonella were tested. Results showed the potential probiotic activity of isolated strains. L. plantarum strains survived in the presence of 1% bile salts, they possessed acidification ability, antibacterial activity and significantly attenuated the growth of S. Typhimurium in brain heart infusion broth. All tested L. plantarum strains were able to adhere to Caco-2 cells and significantly impair the adhesion of S. Typhimurium. All three L. plantarum strains exhibited significant probiotic potential and anti- Salmonella activity; therefore, further testing on in vivo models should follow.

In this study, the effect of an isolated and well-characterised autochthonous starter culture, glucose and maltodextrin ( w =0.8%) and temperatures of 12 and 20 °C 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. Furthermore, pH value was continuously measured throughout the twenty-day fermentation period. The addition of an autochthonous starter culture and sugars and different fermentation temperatures significantly (p<0.05) affected the instrumental colour and texture parameters of the Slavonian kulen. The fermentation was most intense in the samples with added autochthonous starter culture and 0.8% glucose, and fermented at 20 °C. Microbiological analysis showed that samples with added autochthonous starter culture and fermented at higher temperature contained a higher number of lactic acid bacteria and coagulase-negative staphylococci and were safe. Sensory evaluation confirmed the outcomes of physicochemical and microbiological analyses and showed differences among samples fermented at two different temperatures and with added glucose or maltodextrin and an autochthonous starter culture.

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.

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.

This study investigated 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 25.8 μg kg(-1) in bacon to 17.8 μg kg(-1) 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, it was not statistically significant. The mean OTA reduction achieved with 3-, 7- and 10-kGy γ-doses was approximated to 8.5%, 13.9% and 22.5%, respectively. The storage of irradiated samples (1 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 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 the matrix.

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 .

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.

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.

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., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

The objective of this study was the characterisation of the S-layer protein (SlpA) and its functional role in the probiotic activity of Lactobacillus helveticus M92. SlpA was isolated and identified by SDS-PAGE LC-MS/MS analysis. The slpA gene encoding the SlpA from L. helveticus M92 was sequenced and compared with other well characterised slpA genes. Sequence similarity searches revealed high homology with the SlpA of Lactobacillus strains. Purified SlpA showed significantly better immunomodulatory effects in orally immunised mice than L. helveticus M92 cells after SlpA removal. SlpA is involved in the autoaggregation of L. helveticus M92 cells and coaggregation of L. helveticus M92 with S. Typhimurium FP1 as these processes were negatively affected after SlpA removal from the cell surface. Therefore, the influence of oral treatment with L. helveticus M92 on an oral infection of mice by S. Typhimurium FP1 was investigated. Following the oral immunization of mice, with viable L. helveticus M92 and S. Typhimurium FP1 cells, the concentration in the luminal contents of total S-IgA and specific anti-Salmonella S-IgA antibodies, from all immunized mice was significantly higher compared to the control group or a group of mice infected only with S. Typhimurium FP1. These results demonstrate that the observed reduced infection by S. Typhimurium FP1 in mice with L. helveticus M92 is associated with competitive exclusion in the intestinal tract and enhanced immune protection conferred by the L. helveticus M92 and its SlpA.

Olive 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.

Fungi 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.

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 synbiotic effect of the oral treatment of Swiss albino mice with milk-based diets supplemented with Lactobacillus helveticus M92 and various kinds of prebiotics was investigated. Survival, competition, adhesion and colonization, as well as, immunomodulating capability of Lb. helveticus M92, in synbiotic combination, in the gastrointestinal tract (GIT) of mice, were monitored. After the mice were fed with synbiotics, the lactic acid bacteria (LAB) counts in faeces were increased and reduction of enterobacteria and sulphite-reducing clostridia was observed. Similar results were obtained in homogenates of small and large intestine of mice on the 1st and 14th day, after feeding with synbiotics. After the mice were orally given viable Lb. helveticus M92 cells, alone or in combination with prebiotic, the concentration of faecal SIgA and total serum IgA antibodies from all immunized mice were higher compared with the control. The specific humoral immune response was not evoked after oral administration, therefore their synbiotic application is suitable. Among inulin, lactulose and raffinose, Lb. helveticus M92 in combination with inulin, has shown the best synbiotic effect on intestinal and faecal microflora and immune system of mice.

Aims: To investigate the functional role of surface layer proteins (S-layer) in probiotic strain Lactobacillus acidophilus M92, especially its influence on adhesiveness to mouse ileal epithelial cells., Methods and Results: Sodium dodecyl sulphate polyacrylamide gel electrophoresis of cell surface proteins revealed the presence of potential surface layer (S-layer) proteins, ca at 45 kDa in L. acidophilus M92. Southern blot with pBK1 plasmid, containing slpA gene, gave a positive signal, suggesting that L. acidophilus M92 has a slpA gene coding for the S-layer proteins. S-layer proteins of this strain are present during all phases of growth. The S-layer proteins appeared when cells treated with 5 mol l(-1) LiCl were allowed to grow again. Removal of the S-layer proteins reduced adhesion of L. acidophilus M92 to mouse ileal epithelial cells. Furthermore, the viability of cells without S-layer were reduced in simulated gastric juice at low pH range (2, 2.5, 3) and simulated pancreatic juice with bile salts (1.5 and 3 g l(-1)). S-layer proteins of L. acidophilus M92 were resistant to pepsin and pancreatin, in contrast, the treatment with proteinase K led to a significant proteolysis of the S-layer proteins., Conclusions: These results demonstrated functional role of S-layer; it is responsible for adhesiveness of Lactobacillus acidophilus M92 to mouse ileal epithelial cells and has a protective role for this strain., Significance and Impact of the Study: S-layer proteins have an important role in the establishment of probiotic strain Lactobacillus acidophilus M92 in the gastrointestinal tract.

Aims: To investigate aggregation and adhesiveness of Lactobacillus acidophilus M92 to porcine ileal epithelial cells in vitro, and the influence of cell surface proteins on autoaggregation and adhesiveness of this strain., Methods and Results: Lactobacillus acidophilus M92 exhibits a strong autoaggregating phenotype and manifests a high degree of hydrophobicity determined by microbial adhesion to xylene. Aggregation and hydrophobicity were abolished upon exposure of the cells to pronase and pepsin. Sodium dodecyl sulphate polyacrylamide gel electrophoresis of cell surface proteins revealed the presence of potential surface layer (S-layer) proteins, approximated at 45 kDa, in L. acidophilus M92. The relationship between autoaggregation and adhesiveness to intestinal tissue was investigated by observing the adhesiveness of L. acidophilus M92 to porcine ileal epithelial cells. Removal of the S-layer proteins by extraction with 5 mol l-1 LiCl reduced autoaggregation and in vitro adhesion of this strain., Conclusions: These results demonstrate that there is relationship between autoaggregation and adhesiveness ability of L. acidophilus M92, mediated by proteinaceous components on the cell surface., Significance and Impact of the Study: This investigation has shown that L. acidophilus M92 has the ability to establish in the human gastrointestinal tract, which is an important determinant in the choice of probiotic strains.