1. Comparative genomic analysis between Lactobacillus delbreuckii subsp. lactis and Lactobacillus delbreuckii subsp. bulgaricus of dairy origin
Voula Alexandraki1, Maria Kazou1, Bruno Pot2, Effie Tsakalidou1*, Konstantinos Papadimitriou1
1Laboratory of Dairy Research, Department of Food Science and Human Nutrition, Agricultural University of Athens, Athens, Greece; 2Institut Pasteur de Lille, Center for Infection and Immunity of Lille, Lille, France
Lactobacillus delbreuckii subsp. lactis and Lactobacillus delbreuckii subsp. bulgaricus are lactic acid bacteria commonly exploited by the dairy industry as starter cultures, mainly for the production of cheese and yogurt. We present here comparative genomic analysis between the recently sequenced genomes of Lactobacillus delbreuckii subsp. lactis ACA-DC 178 and Lactobacillus delbreuckii subsp. bulgaricus ACA-DC 87, isolated from Kasseri cheese and yogurt, respectively. Full chromosome alignments revealed strain specific differences although a high degree of synteny between the two strains was also observed. The core genome contained about 1300 genes while the unique genes of the two strains were also identified. Several of them may have been acquired through horizontal gene transfer. We also predicted potential antimicrobial peptides and CRISPR systems, which may confer resistance against phages. The analyses provide useful insights into the technological potential of the ACA-DC 178 and ACA-DC 87 strains.
Financing: European Social Fund and national resources EPEAEK and YPEPTH (Thales project)
Key words: Lactobacillus delbreuckii subsp. lactis and subsp. bulgaricus, genomic analysis
2. Supporting the development of new products based on treasury of traditional foods: Can educational workshops help?
Peter Raspor1, Mateja Ambrožič2, Sonja Smole Možina2
1Faculty of health sciences, University of Primorska, Izola, Slovenia ; 2Biotechnical faculty, University of Ljubljana, Slovenia
Traditional foods sector is not able to exploit all the innovative opportunities of traditional practical solutions on one side and modern needs of trade, industry and also consumers on another. The project Trafoon, »Traditional Food Network to Improve the Transfer of Knowledge for Innovation« is a 3-year 7FP EU project for improving the transfer of knowledge for innovation in the field of traditional foods, especially in small and medium enterprises (SMEs). One of the tasks of the project partners was to prepare the inventory of needs of national SMEs, which are active in production and marketing of specific groups of traditional products. Survey data acquired topics like products and services, company’s technology state of the art, research and technology development, especially in primary production, processing, packaging, safety, durability, economics and sale of traditional Slovenian grain-mill products and was analyzed according to SWOT principles. Afterwards, we organized a theoretical and practical workshop, which provided desired and missing knowledge and skills to more than one hundred participants.
Key words: traditional foods, knowledge transfer, SWOT analysis, workshop
3. Study of microorganism succession in wild fermentation of Commandaria wine
Efi Aristidou, Dimitris Tsaltas
Department of Agricultural Sciences, Biotechnology and Food Science, Cyprus University of Technology, Limassol, Cyprus
Local microflora is an important component of the ecosystem of the vines and gives specific characteristics and complexity to the wines. The traditional fermentation of wines was conducted by indigenous yeasts, which were found during winemaking process from harvested grapes. Commandaria is the oldest known wine still produced today at the island of Cyprus, using two local varieties, Xynisteri (white) and Mavro (red). The proportion is not regulated and depends on local preferences and availability of grapes. Commandaria is produced only in the 14 producing villages and is tightly regulated by local law (Decree ΚΔΠ41/90) and the EU PDO scheme. The aim of this work is to monitor the fermentation of Commandaria from the variety Mauro and Xynisteri separately for identification of microorganisms of Commandaria from each variety. We also performed isolation and identification of microorganisms from the sun-dried grapes of the two varieties from the mountainous regions of Pitsilia Limassol (villages Zoopigi and Gerassa). For the identification of microorganisms we used the 16S and ITS 1/4 for bacteria and yeast respectively. During fermentation we recorded most important chemical analysis. The initial stages were dominated by species of the genus Aspergillus. During initial steps of fermentation the yeasts Hanseniaspora guilliermondii, H. ovarum, H. opuntiae, Candida zemplinina, and Kluyveromyces thermotolerans were dominant while on the second half Saccharomyces cerevisiae increased and dominated. In variety Mauro we also identified the yeast Metschnikowia chrosoperlae. These data will help in further studies to produce a high quality product with specific character and complexity and to propose standardization.
Key words: wild fermentation; yeast; wine; Commandaria
4. Donkey Milk: Chemistry, microbiology, functionality
Maria Aspri1, Photis Papademas1*, Dimitris Tsaltas1
Department of Agricultural Sciences, Biotechnology and Food Science, Cyprus University of Technology, Lemesos, Cyprus
Milks from non-traditional animal species i.e. donkey, camel and buffalo are recently gaining momentum mainly due to the fact that they are considered suitable to supplement needs of special population groups (i.e. infants, the elderly). This paper summarizes current research on donkey milk and colostrum produced in Cyprus in respect to its chemical, microbiological and functional compounds (i.e. lysozyme, immunoglobulins) composition. Donkey milk’s gross chemical composition is close to human milk, and is characterised by lower fat (0.5-1.8 %) and protein (1.5-1.8 %) content than bovine milk but more lactose (5.8-7.4 %) with a concentration similar to human milk. Raw donkey's milk microbiological quality is exceptional with very low bacterial counts (log 4 cfu/ml). Furthermore, donkey milk contains a high amount of lysozyme (4g/L), an antibacterial enzyme, which is practically absent, in the milk produced by cows, sheep and goats. Lysozyme is quite a thermostable enzyme which survives LTLT pasteurisation (63 °C/30min). Finally, experiments on donkey milk colostrum and mature milk for the survival of immunoglobulins during thermal treatments (63 °C/30min, 72 °C/15sec) have shown that they weren’t significantly affected when compared to raw milk.
Key words: donkey milk, colostrum, compositon, functional food, health properties
5. Computer modelling in predicting efficacy and safety of food components that interact with Cytochrome P450 3A
Loai Basheer, Zohar Kerem
Institute of Biochemistry, Food Science and Nutrition, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
All organisms are continuously confronted by numerous natural and synthetic chemicals, also known as ‘xenobiotics’, whether through eating or aspiration. Cytochrome P450 (CYP) enzymes are monooxygenases that catalyze oxidative reactions of many substrates in the metabolism of dietary products, steroid hormones and lipids, drugs and environmental pollutants. Members of the CYP3A subfamily are particularly relevant in this respect, due to their abundance in human intestine and liver, and the vast structural diversity of their substrates. Here we report the use of computational tools (e.g. docking in particular) to predict the nature of interaction, i.e. the inhibition of CYP3A4 by selected polyphenolics, including stilbenes, herbals and candidate therapeutics, and to predict interactions between consumed phytochemicals and prescribed drugs. Chemically modified stilbenes, cell culture and in vitro reactions, served to support the prediction by computer modelling of docking. Components in foods, drinks, food additives and orally administered medicines were shown to inhibit CYP3A4 activity and, as a result, increase the actual dose of the drug that reaches the blood circulation in its active form, which often causes unfavorable and long-lasting interactions and probably fatal toxicity. Continuous exposure to these compounds, especially those that activate the xenobiotic nuclear receptor PXR (pregnane X receptor), may lead, in a feedback fashion, to increased expression of CYP3A4 in the intestine, adding complexity to food–drug interactions during extended periods of use. While the above suggests that co-administration of drugs and foods that are rich in polyphenols is expected to stimulate undesirable clinical consequences, it is important to develop predictive tools to group and evaluate the potency of dietary compounds in inhibiting and inducing CYP. Integration of results from several enzymatic models and computer approaches can promote comprehensive understanding of the interactions and potential hazard.
Key words: CYP 3A4, Dietary compounds, food-drug interaction
6. Evodia rutaecarpa fruit extract acts as anti-adhesive of Campylobacter jejuni on stainless steel surface and anti-invasive to human intestine cell line
Katja Bezek2, Marija Kurinčič1, Elvira Knauder3, Anja Klančnik1, Peter Raspor2, Franz Bucar3, Maja Čemažar2, Sonja Smole Možina1
1Department of Food Science and Technology, Biotechnical Faculty, University of Ljubljana, 2Faculty of Health Sciences, University of Primorska, Izola, Slovenia; Ljubljana, Slovenia; 3Institute of Pharmaceutical Sciences, Department of Pharmacognosy, University of Graz, Graz, Austria
The initial interaction of bacteria and abiotic or biotic surfaces is one of the crucial steps in biofilm formation, so reducing the adhesion could be a key antibiofilm strategy. We investigated the antiadhesive potential of sub-inhibitory concentrations of chemically characterized Evodia rutaecarpa fruit extract against Campylobacter jejuni by the quantification of viable cells on the stainless steel surface. The results pointed out a diverse antibiofilm effect of the extract fractions, different strain characteristics and influence of incubation times. Antiadhesive potential of E. rutaecarpa ethanol fruit extract was also tested in C. jejuni infection in vitro - the mucus-secreting, polarized human carcinoma cells HT29-MTX-E12 were used. The number of adherent/invaded C. jejuni on HT29-MTX-E12 cells with and without extract addition was determined 3 h post infection. The results of our study highlighted the potential role of E. rutaecarpa extract as a compound for preventing the formation of microbial communities on abiotic surfaces and lowering the invasion of C. jejuni cells in HT29-MTX-E12 human intestine cell line.
Key words: anti-adhesion, stainless steel surface, HT29-MTX-E12, C. jejuni, E. rutaecarpa
7. Study of wild yeasts mycobiota isolated from indigenous Cypriot vine varieties for selection of technologically competent isolates for vinification
Despina Bozoudi, Efi Aristidou, Elena Savva, Dimitris Tsaltas
Department of Agricultural Sciences, Biotechnology and Food Science, Cyprus University of Technology, Lemesos, Cyprus
This study reports about yeast populations present on grapes of the local Cypriot varieties Xinisteri (white) and Maratheftiko (red). The yeasts were tested for their technological properties as possible starter cultures for vinification, in order to enhance locality and characteristic aroma profile of Cypriot wines. Grapes from 5 different vineyards in Vouni Panayia -an area located in the NW of Cyprus- were sampled at maturation during vintage 2014, in order to obtain an extensive representation of the yeast ecology of the grapes grown in the specific area. In total, 225 yeasts were isolated both from grapes and during fermentation and identified by sequencing using the 5.8S internal transcribed spacer (ITS) rRNA region. The identified mycobiota were mainly composed of Hanseniaspora (57.4 % of the isolates; H. uvarum, H. guilliermondii, H. opuntiae), followed by Cryptococcus (16 %; C. victoriae, C. carnescens, C. chernovii, C. tephrensis, C. oeirensis), Pichia (7 %; P. membranifaciens), Aureobasidium (6.3 %; A. pullulans), Candida (6.3 %; C. zemplinina, C. stellata), Metschnikowia (4.9 %; M. bicuspidata, M. chrysoperlae), Saccharomyces (1.4 %; S. paradoxus) and Rhodotoroula (<1 %; R. colostri). Some biochemical traits were studied (i.e. the ability to produce hydrogen sulphite and the production of biogenic amines).Results showed that 83.6 % of the isolates produced H2S, while 19.7, 46.5, 4.2 and 8.5 % produced biogenic amines from phenylalanine, histidine, arginine and tryptophan, respectively. None of them decarboxylated tyrosine. The study provides preliminary information on the fungal species present on Xinisteri and Maratheftiko grapes in the Vouni Panayia region. Further studies are planned to confirm the species composition reported.
Keywords: yeast, Xinisteri, Maratheftiko, Cyprus, wine, grape, starter culture
8. Fatty acid methyl and fatty acid ethyl esters in Slovenian olive oil
Milena Bučar-Miklavčič1,2, Erika Bešter1, Bojan Butinar1, Ana Miklavčič Višnjevec1, Vasilij Valenčič1, Lanfranco Conte3
1Science and Research Centre, University of Primorska, Izola, Slovenia; 2LABS LLC, Institute for Ecology, Olive Oil and control, Izola, Slovenia; 3University of Udine, Italy
Alkyl esters are synthesized already in olive fruits during oil production. The synthesis is in particular intensive in damaged fruits, in which free fatty acids are formed from triacylglycerols and methanol and ethanol are formed in pectin hydrolysis and fermentation processes. Esters are then formed from free fatty acids and alcohols. High concentration of alkyl esters are usually present in olive oils produced from damaged fruits and this oil usually is classified as Lampante on the basis of sensory defects. So the content of alkyl esters become a new analytical parameter suitable to check for quality of virgin olive oils. Non filtered oils can undergo more easily to an increase of alkyl esters concentration as depending on the presence of enzymes and pectins and water that can catalyse the formation of free methanol in the case of methyl esters. Ethyl esters can be formed as a consequence of lipase activity. The Reg. (UE) 61/2011 established the limits of alkyl esters for classification of virgin olive oils and the Reg. (UE) 1348/2013 modified these limits. During three-year project UELIJE II the alkyl esters content was determined in olive oils produced in Slovenska Istra and Goriška Brda. The analysis of alkyl esters was carried outh both on fresh oils and on stored oils. In the case of Slovenian oils, the amount of alkyl esters in oils from crop years 2011 and 2013 were similar, oils from crop year 2012 on the other hand showed higher amounts of methyl and ethyl esters, which might be a consequence of drought.
Keywords: olive oil, alkyl esters, methyl esters, ethyl esters
9. Fatty acid composition of different vegetable oils and their nutritive potential
Djuričić Ivana, Timić Jasmina, Jovic M, Zrnić Milica, Šobajić Sladjana
Department of Bromatology, Faculty of Pharmacy, University of Belgrade, Serbia
Vegetable oils are important ingredients of diet and their usage can influence the intake and ratio of dietary saturated and unsaturated fatty acids and consequently can affect health. The best example is olive oil that is an important part of Mediterranean diet and rich source of n-9 monounsaturated fatty acid, and has been reported to be inversely correlated with cardiovascular risk factors. Vegetable oils are also good sources of essential fatty acids: n-6 linoleic (LA) and n-3 alpha-linolenic acid (ALA). The aim of this study was to determine fatty acid composition of different unfamiliar vegetable oils in Serbia in order to evaluate their nutritive potential. Vegetable oils were purchased in local health food stores. All 19 different vegetable fats and oils were classified according to their nutritional properties into 4 groups: high-SFA, high-MFA, high-PUFA-LA, and high PUFA-ALA. For the purpose of nutritive value comparison the sunflower oil was used as the most commonly consumed vegetable oil in Serbia (with >60 % of LA belongs to PUFA-LA group). In the high-SFA group were coconut and palm oil, and therefore had the highest thermal stability, and could be recommended for frying purpose. Oils with dominant monounsaturated oleic acid were olive oil (78.5 %), followed by almond oil (62.6 %), apricot kernel oil (61.7 %), and peanut oil (44.4 %). Grapeseed oil, black cumin oil, wheat germ oil, and poppyseed oil had the highest content of polyunsaturated linoleic fatty acid (50-66 %; high-PUFA-LA group) and are nutritionally similar to the sunflower oil. Evening primrose oil had the highest LA content but also had exclusively significant content of n-6 gamma-linolenic acid (8.6 %). In the group of high-PUFA-ALA were flaxseed oil (51.2 % ALA) followed by hemp seed oil (16.2 %), rapeseed oil (8.1 %), and soyabean oil (5.8 %). Erucic fatty acid (22:1) which is known for its cardiotoxicity was found in mustard oil sample in high quantity (41.6 %). Pumpkin seed oil and sesame seed oil had highly balanced MUFA:PUFA ration (1:1). The best ratio of essential n-6 (LA) and n-3 (ALA) fatty acids was found in hemp seed oil (3:1). It is important to identify fatty acid composition of vegetable oils and fats to improve understanding of their quality, stability and nutritive values.
Key words: vegetable oils, SFA, MUFA, PUFA LA, PUFA ALA
10. Microbiological contamination of mussels from Slovenian coastal waters
Urška Henigman1, Majda Biasizzo1, Stanka Grebenc1, Ivan Toplak1, Mitja Gombač1, Andrej Steyer2, Mateja Poljšak-Prijatelj2, Mateja Ambrožič3, Irena Fonda4, Andrej Kirbiš1, Darja Barlič-Maganja5
1Veterinary Faculty, University of Ljubljana, Ljubljana, Slovenia; 2Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia; 3Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia; 4Fonda s.r.l., Portorož, Slovenia; 5Faculty of Health Sciences, University of Primorska, Izola, Slovenia
In the period from 2006 to 2008, samples of Mediterranean mussels (Mytilus galloprovincialis) were examined for the presence of Vibrio. parahaemolyticus, verotoxigenic E. coli (VTEC), noroviruses (NoV) and hepatitis A virus (HAV). Mussels were collected at three Slovenian harvesting areas: Seča, Strunjan and Debeli rtič. A small number of wild mussels were collected from the area of Piran. The goal of our study was to determine the level of bacterial and viral contamination of shellfish from Slovenian coastal waters, which has been basically unexplored to date. The presence of V. parahaemolyticus and also NoV were confirmed in our study. E. coli is often present in mussels from Slovenian coastal waters (indicating faecal contamination), but VTEC were not detected. HAV were not detected in mussels, which correlates with the low number of human infections in Slovenia. Infections with NoV are more common in Slovenia, so it is not surprising that they were also detected in Mediterranean mussels. We interlinked these results with the location of harvesting areas. Sea current, dense shipping and the influx of streams and rivers contributed to the contamination of the sea and, consequently, also mussels living in this area with diverse strains of NoV.
Key words: food contamination, shellfish, V. parahaemolyticus, E. coli, NoV, HAV, Slovenia
11. Adaptation of Streptococcus macedonicus and Streptococcus thermophilus in milk.
Common strategies, distinct ways
Maria Kazou1, Voula Alexandraki1, Pierre Renault2, Bruno Pot3, Effie Tsakalidou1*, Konstantinos Papadimitriou1
1Laboratory of Dairy Research, Department of Food Science and Human Nutrition, Agricultural University of Athens, Athens, Greece; 2INRA, AgroParisTech, Jouy-en-Josas, France; 3Institut Pasteur de Lille, Center for Infection and Immunity of Lille, Lille, France
Lactic acid bacteria (LAB) are the most important bacteria in food fermentations. Among the genera included in LAB is the Streptococcus genus containing a number of species that are commensals and opportunistic pathogens. Up to now, only one species in the Streptococcus genus, namely S. thermophilus, has been traditionally used as a starter in milk and is considered a domesticated organism. However, Streptococcus macedonicus, belonging to the S. bovis/S. equinus complex (SBSEC), can be also found in milk. In this study, S. macedonicus was fully sequenced and a comparative analysis was performed against all other SBSEC members. According to our analysis, S. macedonicus missed several genes encoding enzymes for the degradation of complex plant carbohydrates typically met in the genome of S. gallolyticus, indicating a reduced ability to survive in the gastrointestinal tract of herbivores. In addition, two pilus operons necessary for the adhesion of Streptococcus gallolyticus to the host and the initiation of infection were absent from the S. macedonicus genome. Adaptation of S. macedonicus to the milk environment was supported by the presence of an extra lactose operon. Finally, the plasmid pSMA198 found in S. macedonicus also provided evidence about the habituation of the species to milk. Our findings support adaptation of S. macedonicus to the rich in nutrients milk environment characterized by diminished biosynthetic capabilities and loss of pathogenicity-related genes in parallel to gene gain events through horizontal gene transfer, similarly to S. thermophilus. Comparative analysis between S. macedonicus and S. thermophilus though revealed numerous species-specific differences at the genomic and proteomic level, suggesting that common strategies can be used by truly divergent organisms during their evolutionary history.
Financing: European Social Fund and national resources EPEAEK and YPEPTH (Thales project)
Key words: S. macedonicus , S. thermophiles, milk, genomic analysis
12. Monitoring of phenotypic changes in brewer's yeast during serial repitching
Nataša Kočar1, Jure Zupan2,3, Neža Čadež2, Polona Jamnik2, Sonja Smole Možina2, Matej Oset1, Peter Raspor2,3
1Pivovarna Laško d. d., Laško, Slovenia; 2Biotechnical faculty, University of Ljubljana, Ljubljana, Slovenia; 3Faculty of Health Sciences, University of Primorska, Izola, Slovenia
Serial recycling of yeast biomass, i.e. repitching, has been a common practice in brewing. Repitching is usually performed 6 to 12 times. The aim of our study was therefore to monitor changes in physiological, genome and proteome changes along the re-pitching cycles at industrial and laboratory-scale. The laboratory fermenter system was constructed with the aim to mimic the industrial process. One day after each repitching, the following tests on yeast biomass were performed: cultivability (CFU), viability, vitality, optical density, cell counting etc. We also performed the phenotypic microarray analysis using the Omnilog system. Regarding the cautiousness around the eighth repitching in breweries, we observed no significant changes in yeast physiology. First deficiencies in metabolism were observed after the fifteenth repitching. Genome stability along the re-pitching cycles was analyzed by polymorphisms in microsatellite alleles along the genes of technological importance. The hybrid nature of the strain TUM34/70 revealed few changes in microsatellite frequency differences confirming unstable nature of lager yeast. We determined 83 differentially expressed proteins, either in the terms of increased or decreased levels of expression relative to the first fermentation. Major changes in protein levels were detected in 12th successive use of the yeasts.
Keywords: Brewing, repitching, starter culture, TUM 34/70, phenotype, genome, proteome
13. Verification of putative safety issues of probiotic Saccharomyces boulardii
Matic Konjar1, Jure Zupan1, Peter Raspor1,2
1Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia; 2Faculty of Health Sciences, University of Primorska, Izola, Slovenia
Even though probiotic yeast Saccharomyces boulardii is considered to be safe, we can find increased reports of fungal infections in immunocompromised patients after treatment with S. boulardii. Since the cause of such infections is still unclear, the purpose of this study was to examine the potential danger of this probiotic yeast. We studied the susceptibility of commercial S. boulardii strains to antifungal agents, possible modulatory effects of medical substances on antifungal sensitivity, strains invasiveness, and their viability at different pH values. Growth kinetics at different pH values (2, 5, 6.5 and 8), showed that the concentration of cells in the commercial products met the minimal concentration of probiotics necessary for the positive effects. The majority of probiotic yeasts did not show resistance to tested antifungal agents (fluconazole, itraconazole, amphotericin B and caspofungin) and were agar-noninvasive. Testing the modulator effects on the other hand showed antagonistic effect of the immunosuppressant MPA (mycophenolic acid) to the sensitivity of probiotic yeasts to antifungal agents itraconazole and fluconazole and synergistic effect of immunosuppressant FK506 (tacrolimus) to the sensitivity of the probiotic yeasts to mentioned antifungal agents. The study showed that the tested commercial S. boulardii products were not resistant to antifungal agents and were not dangerous from the standpoint of invasive growth into agar.
Key words: S. boulardii, invasivness, resistance, antifungal agents, fungal infections
14. A double compartment membrane system for studying mixed fermentations of wine yeasts Dekkera bruxellensis and Saccharomyces cerevisiae
Janez Kosel1,2, Neža Čadež1, Richardo Duarte2, Laura Carretto3, Dorit Schuller2 in Peter Raspor1
1Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia; 2University of Minho, Department of Biology, Braga, Portugal; 3University of Aveiro, Centre for Environmental and Marine Studies, Aveiro, Portugal
Yeast Dekkera bruxellensis causes wine spoilage, especially through the formation volatile phenols. These aromatic molecules can form undesirable aromas in concentrations as low as 600 µg/L. Our goal was to identify microbial interactions between yeasts Dekkera bruxellensis and Saccharomyces cerevisiae using transcriptomic and metabolomic applications. In order to separate the two microorganisms during wine fermentations a double compartment membrane system was developed. Our results showed that the presence of D. bruxellensis induced S. cerevisiae genes involved in response to stress and sulphur metabolic process. We identified stress responsive genes mainly associated with osmotic and anaerobic stress state. Furthermore sulphur amino acid permease and thiamine biosynthetic genes were also induced. This indicates for a competition for oxygen and sulphur containing compounds between S. cerevisiae and D. bruxellensis. A lack of oxygen could explain the increase in the accumulation of ethyl esters and fatty acids in mixed cultures.
Key words: Dekkera bruxellensis, Saccharomyces cerevisiae, wine fermentation, transcriptome, metabolome, membrane bioreactor
15. The potential of mediteranean herbs in bread preparation
Faculty of Health Sciences, University of Primorska Izola, Slovenia
The supplement of three mediteranean herbs rich in natural antioxidants; melissa Melissa officinalis, rosemary Rosmarinus officinalis and common thyme Thymus vulgaris have been tested in white and whole grain bread preparation. The influence of the concentration of milled herbs on organoleptic characteristics, bread volume and freshness of the final product were studied. The concentration of herbs varied from 0,2 and 2 %. The research shows a positive correlation between supplement of herbs and the organoleptic characteristics. The best taste of bread has been achieved by 1-1,5 % of melissa, and up to 0,5 % of rosemary or thyme. The result of adding herbs is a slightly smaller volume of the bread. The final freshness of bread after 48 hours has not been improved. Correlations between different concentrations of herbs and microbiological stability of bread showed that rosemary in concentration higher than 1 % expressed slight influence on moulds appearance in packed bread slices.
Key words: melissa (Melissa officinalis), rosemary (Rosmarinus officinalis), common thyme (Thymus vulgaris), bread
16. Exposure of Campylobacter jejuni to subinhibitory concentrations of pinocembrin affects the bacterial virulence potential
Jasna Kovač1, Zuowei Wu2, Anja Klančnik1, Darinka Vučković4, Franz Bucar3, Maja Abram4, Qijing Zhang2, Sonja Smole Možina1
1Department of Food Science and Technology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia; 2Department of Veterinary Microbiology and Preventive Medicine, Iowa State University, Ames, USA; 3Department of Pharmacognosy, Institute of Pharmaceutical Sciences, University of Graz, Graz, Austria; 4Department of Microbiology, Medical Faculty, University of Rijeka, Croatia
The prevalence of antimicrobial resistance of foodborne pathogen Campylobacter jejuni increases, so new natural antimicrobials are becoming attractive alternatives. One of such compounds is pinocembrin, present in honey and therefore a part of normal healthy diet in low concentrations. First, anti-Campylobacter activity of pinocembrin was studied in-vitro. Beside minimal inhibitory concentrations (MICs), the whole-genome transcriptomic response of C. jejuni to pinocembrin with the microarray approach was determined, as well as the effects on bacterial virulence potential in systemic infection in BALB/c mice model. MICs of pinocembrin were found at the median concentration of 39 mg/L on 31 Campylobacter isolates. The culture mimicking the traits of multidrug-resistant phenotype ΔcmeR was used in further experiments. The 2-h pinocembrin pre-treatment of C. jejuni with sub-inhibitory concentration resulted in bacterial decrease in mice liver 8 days post-infection as well as in decreased expression of ribosomal proteins and up-regulation of several NADH dehydrogenase sub-units and iron uptake proteins, suggesting disrupted the protein production, redox cycle and iron metabolism, which may cause disadvantage in host environment during the infection.
Funding: BI-US/11-12-043, WTZ SI 03/2011.
Key words: Campylobacter jejuni, pinocembrin, antimicrobial activity
17. Physiological characteristic of Brettanomyces bruxellensis strains isolated from different beer and wine related environments
Luka Kranjc1, Neža Čadež2, Peter Raspor1
1Faculty of Health Sciences, University of Primorska, Izola, Slovenia; 2Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
Until recently the yeast Brettanomyces bruxellensis has been regarded mainly as a wine spoilage organism due to its ability to cause taint of wine. This property is mainly related to its ability to tolerate high ethanol levels and production of volatile phenols. Although it has been an indispensable organism for production of certain kinds of beer, recent studies suggested that its high ethanol tolerance and ethanol production rates might make B. bruxellensis useful in bioethanol production processes as well. In this study, 11 strains of B. bruxellensis were tested for selected physiological parameters – cell growth, glucose consumption, ethanol, glycerol and acetic acid production and 4-vinylphenol conversion. Results showed wide range of specific growth rates from 0.022 to 0.095 h-1. All of the tested strains managed to reach higher concentrations of metabolically active biomass and yielded lower amounts of glycerol then Saccharomyces cerevisiae and variable amounts of acetic acid. All of the tested strains managed to convert all of the 4-vinylphenol to 4-ethylphenol in four days. Physiological data showed, that B. brettanomyces strains of similar origin clustered together indicating certain adaptation to specific environments. These clusters correlated well also with the chromosomal make-up of the strains. Based on these results, some of the tested strains indeed might have the potential to be used in industrial environments.
Key words: Brettanomyces bruxellensis, physiological characteristics, wine, beer
18. Wellfood – challenge for future
Aleksandra Krumpak1, Bojan Butinar2,3, Matjaž Hladnik2,4, Milena Bučar Miklavčič2,5 , Maja Podgornik2,4
1Art of Life Association, Rogaška Slatina, Slovenia; 2Science and Research Center, University of Primorska, Koper, Slovenia; 3Faculty of Health Sciences, University of Primorska, Izola, Slovenia; 4Faculty of Mathematics, Natural Sciences and Information Technologies, University of Primorska, Koper, Slovenia; 5LABS LLC - Institute for ecology, olive oil and control, Izola, Slovenia
Crossborder project Wellfood (www.wellfoodproject.eu) interdisciplinary examines many aspects of agri-food and nutrition in the context of the innovation. UP SRC in the project elaborated 4 e-training modules: 1. Labeling for food-quality and safety, 2. Sensory analysis of olive oil-impact of technology on the quality of the oil, 3. Transfer of knowledge-examples of cooperation between research institutions, businesses, producers 4. Innovation in agriculture and agribusiness. E-modules in Slovenian and English are available on the link http://www.assam.marche.it/elearning/. In the final phase of the project two technology pilot forecast schemes (review) were elaborated for Organic Oliveculture and Organic Apiculture in the crossborder area (Slovenia, Albania, Bosnia and Herzegovina, Greece, Italy, Montenegro, Serbia). The main message of the project, defined at the project final conference in Montenegro, is the need for a shift in thinking on innovation. Inventions become good innovation only when they come on the market and have confirmed market value. Trend in innovating is to reduce the share of technological innovation and the growth of innovation in services and other non-technological innovation (new business models, new ways of organizing production and processing, new marketing approaches, new ways of communicating with customers).
Key words: agrofood sector, innovation, e-learning
19. Food safety issues related to Mediterranean diet – case sample of nitrates in vegetables
Eneko Madorran1, Alenka Hmelak Gorenjak1, Ksenija Ekart1, Tomaž Langerholc2
1Faculty of Medicine, University of Maribor, Slovenia; 2Faculty of Agriculture and Life Sciences, University of Maribor, Hoče, Slovenia
Mediterranean diet is based on frequent consumption of olive oil, legumes, unrefined cereals, vegetables and seafood. Apart from well documented health benefits of such foods, there are also risk factors associated to their consumption. For example, vegetables are known to contain high levels of nitrates that are well known environmental pollutants and a recognized health hazard in higher quantities, especially for children. Recently, our laboratory finished a comprehensive study on the influence of food processing on nitrate levels in vegetables. We studied effects of common kitchen processing techniques (PTs) on nitrate content in lettuce, spinach, Chinese cabbage, white cabbage, courgette, potato, carrot and red beet. Nitrate in raw and processed wet weight samples was determined using reverse phase HPLC and the results were statistically evaluated. From the processing techniques (PTs), the influence of washing and washing in combination with boiling decreased nitrate content irrespective of the type of vegetable. PT purée decreased nitrate content in spinach and potato. Some techniques increased nitrate content e.g. grilling of courgette, sauté of spinach, deep-frying of potato. In addition, influence of harvest time and farming type was analyzed. Our results can be used as guidelines for consumers on selection of particular vegetable processing to reduce nitrate intake, as well as for law makers and risk analysis of nitrate exposure in the future.
Key words: nitrate, vegetables, processing
20. Phenolic compounds in fresh and stored Slovenian olive oils
Ana Miklavčič Višnjevec1, Bojan Butinar1, Vasilij Valenčič1, Teja Hladnik1, Erika Bešter1, Milena Bučar-Miklavčič1,2
1Science and Research Centre, University of Primorska, Koper, Slovenia; 2LABS LLC, Institute for Ecology, Olive Oil and Control, Izola, Slovenia
Diets containing olive oil phenolic compounds may have health benefits which include reduction of risk factors of coronary heart diseases, prevention of several types of cancers, and modification of immune and inflammatory responses. During three-year project the determination of phenolic compounds was carried out both on fresh oils and one year and two years stored oils produced in Slovenia. Phenolic compounds in olive oils, such as the derivates of oleuropein and ligstroside, lignans, flavonoids and phenolic acids were extracted by means of 60 % methanol solution and quantified by high-performance liquid chromatography (HPLC). The levels of total phenolic compounds, oleuropein and ligstroside derivates and tyrosol and hydroxytyrosol determined in fresh olive oils varied from 145 to 966 mg/kg (Med=417 mg/kg), 83 to 584 mg/kg (Med=251 mg/kg) and 2 to 97 mg/kg (Med=9 mg/kg), respectively. While the levels of oleuropein and ligstroside derivates significantly decreased, the levels of tyrosol and hydroxytyrosol increased after two years. The total content of phenolic compounds of olive oils can vary greatly on the year basis. The highest levels of total phenolic compounds in the selected samples were found in fresh olive oils from crop year 2012. This could be due to the extreme weather conditions, such as draught in the crop year 2012.
Key words: olive oil, phenolic compounds, storage
21. "ISO-FOOD" ERA Chair for isotope techniques in food quality, safety and traceability
Nives Ogrinc1,2, Sonja Lojen1,2, Milena Horvat1,2, Ljudmila Benedik1,2, Radojko Jaćimović1,2, Barbara Koroušić Seljak1,2, Tina Kosjek1,2, Radmila Milačič1,2, Saša Novak1,2, Maja Remškar1,2, Janez Ščančar1,2, Polona Vreča1,2, David Heath1,2
1Jožef Stefan Institute, Ljubljana, Slovenia; 2Jožef Stefan International Postgraduate School, Ljubljana, Slovenia
The “ISO-FOOD” ERA Chair for isotope techniques in food quality, safety and traceability is acting as an independent Centre at the Jožef Stefan Institute in the field of food (including fodder and forage) analysis in Slovenia. To advance the knowledge of food quality, safety and traceability, the research activities of the ERA Chair focus on interdisciplinary topics combining the expertise in radiochemistry, stable isotope biogeochemistry, electron microscopy and microanalysis and combined analytical techniques (e.g. organic compound profiling, NMR chemical profiling), as well as multivariate statistics and data management, to develop available analytical strategies to verify the origin (provenance) of agricultural produces and foodstuffs, agricultural practices, food contamination, contamination sources and their safety. Nuclear and nuclear-related techniques for food traceability, which are tailored for fingerprinting of food provenance and authenticity, will be developed and combined with elemental markers and biomarkers. Existing databases of authentic food products including wine and olive oils the important products in Mediterranean Basin will be upgraded and extended and could be used to protect their geographical origin.
Keywords: isotopic techniques, pollutants, quality, safety, traceability
22. Focused workshops effectively improved the awareness and knowledge of youth about safe food preparation
Andrej Ovca1, Mojca Jevšnik1, Gregor Jereb1, Peter Raspor2
1Faculty of Health Sciences, University of Ljubljana, Ljubljana, Slovenia; 2Faculty of Health Sciences, University of Primorska, Izola, Slovenia
Education and training about basic food safety principles are emphasized as important factors contributing to the reduction of foodborne illnesses. However, it is of crucial importance that the message be specifically tailored and task-specific with regards to the needs of the target group. A cross-sectional pre-test/post-test survey with a control group was administered among 11-years old children (N = 1272). Workshop addressed the most common mistakes done by consumers during food preparation. In the intervention group, after the baseline was determined, one week later the participants took part in the focused 45 minutes workshop. After the workshop was concluded, participants in the intervention group answered the questionnaire once again, one week (1st follow-up) and one month (2nd follow-up) later. Participants in the control group did not take part in the workshop. The results show considerable change in susceptibility towards food-related risk and demonstrate that activities during the workshop were recognized by respondents as feasible in the domestic environment. The improvements are of a long-term nature. Improvement becomes more significant if substantiated with practical activity. The results are also proving that this kind of teaching style is appropriate to influence young people’s perception towards food-related risk.
Keywords: food safety, education, microbiological hazards
23. Declarations, forward looks and position papers: The tools to stimulate development and networking initiatives
Faculty of health sciences, University of Primorska, Izola, Slovenia
Declaration is a strategic document which gained on its legitimacy in the last century. Although the document is not legally binding act, many experts coming from field of microbiology, food technology and nutrition opted for it. Result of this is Declaration of Microbiology, which was for the first time presented to the public in 2003 at the first Congress of European Microbiologists, and the Declaration on Food, Nutrition and Technology (EFTND), which was for the first time presented to the public in 2008 at the first European Congress on Food, Technology, and Nutrition, also in Ljubljana. Content of the declarations rises from basic human rights linked to the area of expertise and to the field of communication and knowledge transfer between experts and by that between scientific fields. In last decade forward looks were performed in close collaboration with the EC services involved and the SCAR working group. We review and analyze foresight information relating to European agriculture in relation to 8 major driving forces. On the other hand we also bulled scenarios on how the future may develop, based on a coherent and internally consistent set of assumptions about key driving forces and relationships in COST/ESF umbrella. In this respect SCAR scenario from 2007 and COST/ESF scenario from 2009 was analyzed. The third level of documents is so called position paper as coned in the topic of food wastage in 2014. All mentioned documents are important to bridge negative impact of past development with future trends in comparison to current state of the art.
Key words: declaration, food, microbiology, nutrition, technology, forward looks; scenarios, position papers
24. Food, Nutrition and Health: Intimate Connection
Faculty of Health Sciences, University of Primorska, Izola, Slovenia
Institute for Food, Nutrition and Health (IŽPZ) is a good point for the integration of research activities in the field of nutrition and health sciences. A strong connection base is in this context linked to the sustainable development of production, processing and food preparation and preservation of human health can be foreseen along the spectrum of the activities. Not only the food diet also lifestyle change traditional society which is more and more oriented to urban areas that has less and less contact with the natural environment. Therefore, it is necessary to begin to offer alternatives to diet and lifestyle in order to maintain sustainable development and a healthy human population in a healthy environment. Intersection of three Institute activities contributes the necessary innovations and awareness in both technical and technological, as well as anthropological view. Starting from the basic principles of current state we should take in the next decade the opportunity to develop it further along following trends: A. Using opportunities of cultural plants, animals and micro-organisms necessary for self-sufficiency in Mediterranean region; B. Recording of regional foods and dietary and life patterns for the purpose of culture preservation and development of new solutions with traditionally known values; C. The development of potent foods, nutrients and products for humans in the optimal lifecycle and health complex situations; D. Design life patterns Platform which will keep a man from rigid urban structures in contact with nature and healthy lifestyle. Diet and way of life are profoundly changing the traditional society and stream it into urban areas that have less and less contact with the natural environment. Therefore it is necessary to begin to offer alternatives in the diet and lifestyle in order to maintain sustainable development and a healthy human population.
Key words: food, nutrition, health, institute, vision
25. Study of microorganism succession in production and curing of traditional Pitsilia (Cyprus) sausages and ham
Eleni Savva, Photis Papademas, Dimitris Tsaltas
Department of Agricultural Sciences, Biotechnology and Food Science, Cyprus University of Technology, Limassol, Cyprus
Cured meats of “Pitsilia” are one of the main traditional products of the mountainous region of Pitsilia-Cyprus. Pitsilia is a rocky land on very steep slopes known for producing apples, grapes, wine and cured meats. The region complemented by eastern, north and south eastern part of the Troodos Mountain at elevations between 500 and 1,600 meters and includes villages from the districts of Limassol and Nicosia. Cured meats are made in small scale production units, based on the experience of the producer, using the natural microbial flora of red local wine and the environment. Sausages and Ham (called “Chiromeri”) are the most popular cured meats of “Pitsilia”. The aim of this study was the characterization of microbial succession that occurs in Sausages and Ham of “Pitsilia”. Microbiological (enumeration and isolation of microorganisms) and molecular identification by sequencing the 16S rRNA and ITS rRNA were performed from isolated microorganisms from all stages of the production processes. In addition, swab samples were also collected from smoking-houses for molecular identification of the natural microflora. The main microorganisms that were identified in sausages were Saccharomyces cerevisiae, Lactobacillus sakei and Candida spp.. From the samples that were collected by swab, Staphylococcus saprophyticus, Debaryomyces hansenii and Candida spp. dominated. Detailed data will be presented in order to assist further characterization of these fermented products.
Keywords: cured meats, wine, sausages, ham, yeast, bacteria, L. sakei, S. cerevisiae
26. Mead – Nectar of gods rediscovered
Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Bratislava, Slovakia
Creating new beverages, mead, often referred to as "honey wine" have been rediscovered as a health tonic drink with a good level of antioxidants from honey. The basic analytical parameters and aroma compounds of three Slovak and two South African meads were summarised. The ethanol concentration of the Slovak meads was about 13.5 % (v/v), the residual sugars, depending on the mead style, ranged approximately from 140 g/ to 200 g/l. In the South African meads, the average ethanol concentration was 12 % and the average residual sugar content about 70 g/l. The residual sugar content in all types of the Slovak meads was significantly higher. The acidity of the South African meads was slightly higher than that of the Slovak ones, while the extract and protein contents were higher in all of the Slovak meads. No significant differences were found in the total polyphenol content, which ranged from 178 mg/l to 242 mg/l of gallic acid equivalents. Ethyl acetate represented the main component of all volatile compounds across all the samples tested, with a significantly higher concentration in the Slovak meads (46.3–60.03 mg/l) compared to the South African ones (16.35 mg/l–16.97 mg/l). Higher alcohols were more prevalent in South African meads.
Financing: the Scientific Grant Agency of the Ministry of Education of the Slovak Republic and the Academy of Sciences, registration number 1/0560/14.
Key words: mead, honey antioxidants, beverages
27. Microbiological safety and stability of bee pollen
Katarina Šimunović1, Nataša Lilek2, Klemen Schara1, Manca Perko1, Dejan Vozlič1, Boštjan Noč2, Sonja Smole Možina1
1Biotechnical Faculty, University of Ljubljana, Slovenia, 2Slovenian Beekeepers´ Association, Brdo pri Lukovici, Slovenia
Bee pollen is an important nutrient for bees, and due to its composition and its health benefits, it is also important in human nutrition. Bee pollen is a seasonal product and can be heavily contaminated by microorganisms, which can influence its quality, safety and stability. During this research we have studied the influence of bee pollen trap materials, the time and frequency of collecting, the temperature and the duration of storage, and the temperature of drying, on the microbiological indicators of the quality and safety of bee pollen. Fresh, unprocessed bee pollen is a quickly perishable foodstuff with a high microbial load and is durable for only a couple of days at room temperature. Storage in a refrigerator only slightly prolongs its shelf-life. Different bee pollen trap materials had little influence on the microbiological count of the bee pollen due to the large microbial load of the bee pollen itself. Beside freezing, the optimal way of preserving bee pollen appears to be drying it at 35 °C for 48h, as this ensures stability (especially prevents yeast spoilage) and does not deteriorate the texture and sensory properties of bee pollen. The results will be used for preparation of the guidelines for safe production and consumption of bee pollen.
Keywords: bee pollen, microbiological safety, quality, stability
28. Cell surfaces hydrophobicity create potential for yeast Candida spp. and Pichia spp. to adhere to different surfaces
Ružica Tomičić1, Marija Kurinčič2, Peter Raspor3
1Faculty of Technology, University of Novi Sad, Novi Sad, Serbia; 2Biotehniška fakulteta, Univerza v Ljubljani, Ljubljana, Slovenija; 3Fakulteta za vede o zdravju, Univerza na Primorskem, Izola, Slovenija
The aim of this study was to assess the potential of Candida and Pichia species to adhere to stainless steel (AISI 304) material with different degrees of surface roughness (Ra = 25.20 – 961.9 nm) and polystyrene. The influence of cell surfaces hydrophobicity and surface roughness of stainless steel on the degree of yeasts adhesion was investigated. Cell surfaces hydrophobicity (CSH) was measured by the microbial adhesion to hydrocarbon (MATH) method. The adhesion of the yeasts strains to polystyrene and stainless steel was assessed by crystal violet staining. The results showed that all Candida and Pichia strains have been able to adhere to polystyrene and stainless steel surfaces in a species- and strain-dependent manner, with C. albicans showing a higher ability to adhere on the both surfaces compared with non-albicans Candida species, while P. pijperi showed higher ability to bind to the stainless steel but less to the polystyrene than P. membranifaciens. CSH values showed that tested non-albicans Candida strains and Pichia strains were strongly to moderately hydrophobic while C. albicans strain was moderately hydrophilic. No correlation was found between cell surfaces hydrophobicity and adhesion of yeast cells to polystyrene and stainless steel surfaces (P > 0.10). There was significant difference in cell adhesion on all types of stainless steel surfaces for all tested strains (P < 0.05).
Key words: adhesion, Candida spp., Pichia spp., polystyrene, stainless steel surfaces, cell surfaces hydrophobicity
29. Probiotic yeast Saccharomyces boulardii (nom. nud.) modulates adhesive properties of Candida glabrata
Zorica Tomičić1, Jure Zupan2, Tadeja Matos3, Peter Raspor2
1Institute of Food Technology, University of Novi Sad, Novi Sad, Serbia; 2Faculty of Health Sciences, University of Primorska, Izola, Slovenia; 3Institute of microbiology and immunology, Medical faculty, University of Ljubljana, Ljubljana, Slovenia
Following the widespread use of immunosuppressive therapy together with broad-spectrum antimycotic therapy, the frequency of mucosal and systemic infections caused by Candida glabrata has increased significantly. C. glabrata is considered as the second most frequently isolated pathogenic yeast after Candida albicans. Due to increasing resistance of C. glabrata to existing drugs, it is very important to look for new strategies helping the treatment of such fungal diseases. An increasing number of potential health benefits are being attributed to probiotic treatments. They include various bacterial probiotics, while among yeast only Saccharomyces boulardii (nom. nud.) is used extensively. S. boulardii is very efficient as a biotherapeutic agent for the prevention and treatment of intestinal diseases, mainly diarrhea. The beneficial effect of S. boulardii in the case of C. glabrata infections have not been studied yet. Also, the influence of S. boulardii presence on the efficiency of C. glabrata virulence traits, like adhesion and antimycotic resistance, is not known. Therefore, we tested the adhesion of 48 C. glabrata strains in a co-culture with S. boulardii to polystyrene surface at different temperatures, pH values and in the presence of three clinically important antifungal drugs. We show a significant repressive effects of S. boulardii on C. glabrata adhesion, resulting in lower effective concentration of antimycotics, but we also show that these effects, including a possible stimulative effect on C. glabrata adhesion, is highly dependent on conditions.
Keywords: adhesion, Candida glabrata, Saccharomyces boulardii, antimycotics
30. New biosensors to detect pollutants in the vicinity of fish farms
Valentina Turk1, Oliver Bajt1, Willem Haasnoot2, Matthew Burlington2, Duarte Tito3 in Sarah Heub4
1Marine Biology Station Piran, National Institute of Biology, Piran, 2RIK-RIKILT Institute of Food Safety, The Netherlands; 3EPL-Elysium Project Ltd., United Kingdom; 4CSEM SA, Microelectronics Division, Switzerland
Detection of endocrine disrupting compounds in food or water is important for protection of water and food as well as sensitive environmental sites and to reduce the risk of toxins entering the food chain. Preliminary measurements of estrogens were performed with new biosensors that were developed and tested within the RADAR project. Biosensors with the protein structures similar to aquatic organisms’ receptors for binding endocrine disruptive compounds such as estrogenic substances and polycyclic aromatic hydrocarbons were designed. The seawater samples were collected at different sites in the inner part of the Bay of Piran where fish cages are located and in the vicinity of the outlet of the sewage from WWTP Piran. We made several experiments with the Biacore receptor assay and ELISA were used as analytical techniques
Keywords: Biosensors, aquaculture, pollutants, endocrine disrupting compounds, estrogens
31. The influence of slovenian traditional and modified spanish style production technology on the sensory quality of table olives from Slovenian Istria
Vasilij Valenčič1, Erika Bešter1, Milena Bučar-Miklavčič1,2, Bojan Butinar1, Terezija Golob3
1Science and Research Centre, University of Primorska, Koper, Slovenia; 2LABS LLC, Institute for Ecology, Olive Oil and Control, Izola, Slovenia; 3Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
Istrska belica and Storta olive varieties were processed by traditional and modified Spanish style production technology. All the phases (debittering in water or lye treatment, washing and fermentation) of the two processing technologies were monitored for 180 days. The olives fermented spontaneously without starter culture. The biophenol extraction was done with methanol, from 250 mg of freeze dried and powdered sample with the addition of 1 mL of internal standard solution (syringic acid 0.15 mg/mL). Total biophenol content was determined by HPLC analysis. The sensory attributes were determined by nine trained assessors according to the official method of the International Olive Council. The bitterness, hardness and fibrousness of table olives that were produced using the traditional technology, were more intensive compared to the intensities of samples produced with the modified Spanish style. Statistically significant differences (t-test, α<0.05) in the perceived bitterness, sourness and saltiness were determined. Relatively high amount of total biophenols influenced the bitter taste of the produced table olives. Traditional production technology was better for processing the two studied olive varieties and retaining the characteristics of the product.
Key words: table olives, production technology, sensory characteristics, biophenols
32. Thyme and olive extracts are subject to efflux and show anti-adhesive effects against Campylobacter jejuni on polystyrene and intestine epithelial cells
Šikić Pogačar1,2, Anja Klančnik1, Franz Bucar3,
Tomaž Langerholc4, Sonja Smole Možina1
Faculty, University of Ljubljana, Ljubljana, Slovenia; 2Medical Faculty, University of Maribor, Maribor,
Slovenia; 3Institute of Pharmaceutical Sciences, University of Graz, Graz,
Austria; 4Faculty of Agriculture and Life Science, University of
Maribor, Hoče, Slovenia
Campylobacter is the most
frequent cause of food-borne gastrointestinal bacterial infections in the EU.
New strategies targeting early stage infection have become crucial to control
its prevalence. We investigated potential impact of the extracts from agro-food
waste material of thyme (Thymus vulgaris)
and olive leaves (Olea europaea).
Phytochemical analysis of thyme ethanolic extract (TE), post-hydrodistillation
residue (TE-R) and olive leaf extract (OE) was done by HPLC-PDA analysis. With
gene-specific knock-out mutants and efflux-pump inhibitors we showed CmeABC as
the most active pump of C. jejuni, especially in biofilm
form of cells. To avoid selection pressure for the emergence of antimicrobial
resistance, we thus present an alternative strategy that targets Campylobacter adhesion, first step in
biofilm formation and colonization. TE and TE-R in the range 0.2 to 12.5 mg/L
reduced C. jejuni adhesion to abiotic
surfaces by up to 30%. Concentrations of OE from 3.125 mg/L to 200 mg/L reduced
bacterial adhesion to polystyrene by 10% to 23%. On the other hand, C. jejuni adhesion to PSI cl1 cells was
inhibited by almost 30% over a large concentration range of these extracts. Our
findings suggest that TE or TE-R as agro-food waste material and OE as by
products represent a source of bioactive phytochemicals which could be utilized
further as agents that prevent bacterial adhesion.
Key words: bacterial
adhesion, efflux, resistance modulation, C.
33. Inspired from Mediteranean for a better food - quality and healthy pork products from local pig breeds – project TREASURE
Agricultural Institute of
Slovenia, Ljubljana, Slovenia
Project TREASURE (www.treasure.kis.si) “Diversity of local pig breeds and productionsystems for high quality traditional products and sustainable pork chains« aims to enhance the sustainability of pork chains based on local pigbreeds which provide products carrying the image of the highest quality,healthiness and animal welfare care and are typically highly appreciated byconsumers. Mediterranean basin with its pig breeds and products (in particulardry-cured hams) inspired this project since the building up of the projectstarted with the network around the Symposium on Mediterranean Pig. Theactivities of the project are dedicated to i) genetic characterisation of localpig breeds using novel genomic tools and new perspectives (e.g. pilot study ongut microbiota as related to nutrition of pigs), ii) performance of local pigbreeds in contrasted agro-geo-climatic conditions and production systems withspecial emphasis on nutrition e.g. local feeding resources rich in antioxidants,iii) intrinsic quality and healthiness attributes of pork products issue fromthese breeds and production systems, iv) socio-economic evaluation. Allactivities will be driven from the perspective of sustainability i.e.environmental impact, animal welfare, healthiness and quality of meat products,consumer acceptability and market potential.
Keywords: pig, pork products, traditional genetic resources, production systems