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This study revealed that sage and its preparations can be efficiently used in fresh cheese technology to produce kombucha fresh cheese with increased antimicrobial activity against L. monocytogenes, E.coli and S. aureus.

The influence of temperatures (18, 22 and 26 °C), salt (60, 70 and 80 g/kg) and starter culture (0, 0.025 and 0.050 g/kg) on physico-chemical and microbiological changes during fermentation in cabbage heads were investigated. The experiment was set up in industrial conditions, samples were taken after 0, 5, 12, 27 and 62 days in order to determine the changes in color, texture, biogenic amines content, microbiological parameters, pH, aw, total sugar content, total acidity and salt content. Analysis of variance and Principal component analysis were applied to get a better overview of differences between samples and the similarities between different fermentation conditions. Significant color changes and softening of cabbage tissue did not occurred during the entire fermentation process. Cadaverine was not detected in samples containing starter culture, also the results were in range for maximum allowed putrescine and cadaverine doses for all cabbage samples. Total number of molds increased, contrary to number of yeasts on the last examined day in comparison with raw cabbage sample. Enterobacteriaceae were not detected after 5th fermentation day, while sharp increase of lactic acid bacteria number occurred until 12th day, and on the 12th fermentation day was in range of 7.82 to 9.84 log cfu/g. The fermentation process led to decrease in pH, aw and total sugar content, meanwhile total acidity 0.54%-0.89% and salt content 2.08%-3.19% in the cabbage heads increased, in comparison with raw sample where results for total acidity and salt content were 0.13% and 0.05%, respectively. Additionally, according Principal component analysis, temperature of fermentation had the greatest influence on the fermentation process, followed by the application of starter culture and then concentration of added salt.

This research examined the potential use of isolated Serbian autochthonous fungi in lignocellulosic biomass pretreatment. Among 12 isolated fungi, the isolates identified as Trametes hirsuta F13 and Stereum gausapatum F28 stood out as ligninolytic enzyme producers and were selected for potential use in the pretreatment of a waste lignocellulosic biomass. An isolate identified as Myrmaecium fulvopruinatum F14 showed high hydrolytic activity, but negligible ligninolytic activity, and it was selected as a potential producer of important industrial hydrolytic enzymes. Further, the breakdown of lignocellulosic waste, beechwood sawdust, by T. hirsuta F13 and S. gausapatum F28 was examined. Both isolates efficiently degraded biomass, but T. hirsuta F13 exhibited greater selectivity (selectivity coefficient of 1.7) than S. gausapatum F28 (1.1). The isolate F13 was considered a better candidate for the pretreatment, and it was selected for further analysis which involved the use of molasses stillage as a supplement to improve the pretreatment.

Fungal treatment of lignocellulose is an ecologically and economically acceptable method. However, it needs improvement to increase the hydrolysis rate. A novel combination of multiple response optimization of ligninolytic activity ofTrametes hirsutaF13 and supplementation of the lignocellulosic substrate (beechwood sawdust) with sugar beet molasses stillage was employed to improve and manage the desired type of fungal ligninolytic activity leading to a significant enhancement of biomass saccharification. Obtained optimal cultivation conditions (molasses stillage concentration, 13%; substrate moisture, 63%; and temperature, 25 degrees C) provided the desired combination of laccase and manganese-dependent peroxidase activity, and maintained the activities longer and at higher values (51.5 +/- 3.5 U/L and 91 +/- 4.24 U/L, respectively) than the conditions without molasses stillage (21.5 +/- 2.12 U/L and 31.5 +/- 4.9 U/L, respectively). Enzyme hydrolysis of the substrate treated for 7 days in the presence of molasses stillage released 20.54 +/- 0.80 mg/mL fermentable sugars, and 63.58 +/- 1.47 mg/mL from 18-days treated substrate, while sugar concentrations released from the substrates pretreated without the supplementation were 16.84 +/- 0.30 mg/mL and 53.63 +/- 2.16 mg/mL, respectively. The proposed new approach of the lignocellulose supplementation with sugar beet molasses stillage and manipulation and improvement of fungal ligninolytic activity proved to be a promising solution for the enhancement of lignocellulose bioconversion.

Model is based on the fungal birth and death processes. Model is suited for Petri dish. Growth of fungal colony diameter in Petri dish is described with exponential function. The value of diameter is declared as integer variable. Integer variable with 1 mm increment is a discrete state of the system. Time in the system is continuously. Discrete states, continuous time and exponential growth are basis for the application of queuing systems in the Petri dish. Queuing system clearly separated the intensity of birth and death. Difference between the birth intensity and death intensity is declared as the fungal life cycle. Fungal life cycle variable is extra sensitive to the inhibitors effects. The procedures for parameters calculation are mathematically explained, as well as the significance of the obtained parameters. Application of the model is performed for F. verticilloides in control conditions and at 16% concentration of basil and clove essential oils. Life cycle minimum is the synergetic inhibition maximum. For F. verticilloides, synergetic inhibition maximum is at 42% of basil and 58% of clove in 16% essential oil concentration.

This paper aimed to review the publications on mycotoxins' presence in cereals and foodstuffs originated from the Serbian market covering the period from 2005 to 2022. The review covers all the important steps in mycotoxins analysis including sampling, sample preparation, instrumental analysis, and concentration ranges in which the mycotoxins were found. Also, the results were interpreted from the European Union regulation point of view. The review emphasizes the importance of multi-mycotoxins analysis for determining the simultaneous presence of mycotoxins that can negatively affect the Serbian human population. The most frequently used instrumental technique in the mycotoxin analysis of Serbian products was the Enzyme-Linked Immunosorbent Assay followed by the Ultra-High Performance Liquid Chromatography coupled with triple quadrupole mass spectrometry. Most of the studies undertaken in Serbia until now investigated a few groups of matrices such as wheat, maize, milk, and dairy products. Only a few studies involved specific matrices such as nuts, dried fruits, biscuits, cookies, and spices. The review showed that contamination of milk and dairy products with aflatoxin M1 (AFM1), occurred at the very beginning of 2013, was the major health issue related to the population health. The contamination of milk and dairy products with the AFM1 was a consequence of maize contamination with aflatoxins which occurred in the year 2012, characterized by drought conditions. The studies dealing with the analysis of masked and emerging mycotoxins are rare and more attention should be paid to monitoring the presence of these types of mycotoxins in foodstuffs from Serbia.

The objective of this research was to determine chemical composition and to evaluate the antifungal activity of essential oil of Mentha piperita. By the application of GC/MS analysis of essential mint oil, 27 components were identified. The major components were menthol (39.9 %), menton (23.51 %), menthyl acetate (7.29 %), 1.8-cineol (5.96 %), isomenton (5.24 %), isomenthol (3.17 %), trans-caryophyllene (2.88 %), limonene (2.14 %), pulegon (1.38 %), beta-pinene (1.14 %) and piperiton (1.03 %). The quantitative structure– retention relationship (QSRR) was employed to predict the retention time (RT) of Mentha piperita essential oil compounds obtained in GC/MS analysis, using twelve molecular descriptors selected by genetic algorithm. The selected descriptors were used, as inputs of an artificial neural network, to build an RT predictive QSRR model. The coefficient of determination was 0.983, during training cycle, indicating that this model could be used for prediction of RT values for essential oil compounds in Mentha piperita essential oil extracts. Essential oil of Mentha piperita showed antifungal activity on all tested isolates in the minimal inhibitory concentration range of 0.2–1.7 μl/ml and a minimal fungicidal concentration (MFC) range of 1.7–454.5 μl/ml. The most powerful antifungal activity of mint was observed in C. cladosporioides of MFC value 1.7 μl/ml. P. aurantiogriseum showed the lowest sensitivity of MFC value 454.5 μl/ml. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 31029]

Brewer's spent grain (BSG) was used in this study as a support for the immobilization of Lactobacillus paracasei NRRL B-4564, thus enabling the recirculation of immobilized biomass in repeated-batch fermentation. The chemical composition and the energy parameters of the fermented and non-fermented BSG were analyzed and compared. Moreover, the probiotic features of L. paracasei were analyzed to examine the possibility of using fermented BSG as a functional ingredient in ruminant diets. The results obtained indicate that the fermented BSG had significantly higher protein and ash contents, as well as a significantly lower content of fiber fractions. Furthermore, the fermentation process increased the BSG energy content. The analysis of probiotic potential revealed a high tolerance of L. paracasei to pH 2.5 and bovine bile, autoaggregation ability and antimicrobial activity, suggesting that the fermented BSG with immobilized microbial biomass can be used as functional feed in ruminant diets. Globalna potražnja za hranom animalnog porekla raste kao posledica kontinuiranog rasta populacije, urbanizacije i porasta prihoda. Kako bi se zadovoljile potrebe tržišta, upotreba nekonvencionalnih hraniva i sporednih agro-industrijskih proizvoda u ishrani životinja postaje uobičajena praksa. U ovom radu je ispitivan uticaj mlečno-kiselinske fermentacije na kvalitet pivskog tropa kao hraniva za preživare. Pivski trop je korišćen kao nosač za imobilizaciju Lactobacillus paracasei NRRL B-4564, što je omogućilo recirkulaciju imobilisane mikrobne biomase u više uzastopnih šaržnih ciklusa. Po završetku poslednje fermentacione šarže, pivski trop sa imobilisanom biomasom je odvojen od fermentacionog medijuma i osušen, nakon čega su ispitivani hemijski sastav i energetski parametri relevantni za njegovu upotrebu u ishrani preživara. Dodatno, analizirana su probiotiska svojstva L. paracasei, kako bi se u potpunosti sagledala mogućnost primene fermentisanog pivskog tropa kao funkcionalnog hraniva. Utvrđeno je da fermentisani pivski trop ima značajno veći sadržaj proteina i pepela, kao i znatno manji sadržaj svih frakcija vlakana u odnosu na nefermentisane uzorke. Takođe, fermentacija je dovela do povećanja sadržaja energije pivskog tropa. Analizom probiotskih karakteristika, utvrđeno je da L. paracasei ima visoku stopu preživljavanja pri pH 2.5 i u prisustvu goveđe žuči, sposobnost autoagregacije, kao i antimikrobnu aktivnost prema Gram-pozitivnim (Bacillus cereus) i Gram-negativnim (Escherichia coli) patogenim bakterijama. Na osnovu fenotipskih karakteristika L. paracasei, kao i povoljnog uticaja mlečno-kiselinske fermentacije na kvalitet pivskog tropa, može se zaključiti da se fermentisani pivski trop sa imobilisanom mikrobnom biomasom može koristiti kao funkcionalno hranivo u obrocima namenjenim ishrani preživara.

Food contamination by fungi and mycotoxins presents a problem for food safety even today. Since lactic acid (LA) has Generally Recognized As Safe (GRAS) status, the aim of this research was to determine its potential in protection of food against mycological and mycotoxicological contamination. In this study, LA showed an inhibitory effect on the growth of food-borne fungi (Penicillium aurantiogriseum K51, Aspergillus parasiticus KB31, Aspergillus versicolor S72, and Aspergillus niger K95) and on biosynthesis of sterigmatocystin (STE). For the antifungal effect of LA on the growth of food-borne fungi, the disc diffusion and microdilution methods were performed. The effect of LA on the STE biosynthesis by A. versicolor was determined using an LC-MS/MS technique. The largest inhibition zone was observed for A. versicolor (inhibition zone of 24 ± 0.35 mm), while there were no inhibition zones for A. niger and A. parasiticus at all tested LA concentrations. The minimal inhibitory concentration (MIC) of LA on fungi ranged from 25.0 mg/mL to 50.0 mg/mL, while the minimum fungicidal concentrations (MFCs) ranged from 50.0 mg/mL to 100.0 mg/mL. Complete inhibition of STE biosynthesis by A. versicolor was observed at an LA concentration of 50.0 mg/mL. The obtained results showed that LA could be efficient for protection of food against mycological and STE contamination.

This study aimed to test different chemical agents to obtain microbiologically safe industrial hemp seeds that could be used for further food processing (with the reduced total number of microorganisms, total number of moulds and yeasts, and total number of Enterobacteriaceae). In order to obtain seeds applicable for food consumption, optimal storage temperature conditions (room temperature, refrigerator, freezer), method of seed packaging (vacuum/without vacuum), and the application of various chemical treatments (ethanol, sodium hydrogen carbonate, sodium hypochlorite) were tested on the certified industrial hemp seeds, produced in two consecutive years. Optimal storage conditions differed for different microorganisms, and the most optimal storage was at room temperature, for seeds produced in 2018, in the treatment to reduce the total number of Enterobacteriaceae and the total number of microorganisms. When storing seeds from 2018 in order to reduce the number of yeasts and moulds, a slightly lower number was spotted when seeds were stored in a vacuum-sealed bag, at the refrigerator/freezer temperature. For hemp seeds produced in 2019, the most optimal storage conditions were at the refrigerator (for reduction of the total number of Enterobacteriaceae) and freezer temperature (for reduction of the total number of microorganisms). For the reduction of the total number of moulds and yeasts, optimal conditions were at room temperature. Ethanol (75%, v/v) was the most effective disinfectant among the tested chemicals regardless of the initial number of microorganisms, with log reduction of 3.2 (for the total number of Enterobacteriaceae), 2.9 log (for the total number of microorganisms), and total reduction of the total number of yeasts and moulds after 10 minutes, for the seeds harvested in 2019, which were far more contaminated than the seeds harvested in 2018. Considering the price of the disinfection method with ethanol, sodium hypochlorite may be a better solution for the reduction of the number of microbiota on the seeds. Cilj ovog istraživanja bio je ispitivanje različitih hemijskih sredstava za dobijanje mikrobiološki bezbednog semena industrijske konoplje, koje bi se moglo koristiti za dalju preradu u hranu (sa smanjenim ukupnim brojem mikroorganizama, ukupnim brojem kvasaca i plesni, i ukupnim brojem enterobakterija). Da bi se dobilo seme primenljivo za ishranu, optimalni temperaturni uslovi skladištenja (sobna temperatura, frižider, zamrzivač), način pakovanja semena (vakuum/bez vakuuma) i primena različitih hemijskih tretmana (etanol, natrijum hidrogen karbonat, natrijum hipohlorit) su testirani na sertifikovanom semenu industrijske konoplje, proizvedenom u dve uzastopne godine. Optimalni uslovi skladištenja su se razlikovali za različite mikroorganizme, a najoptimalnije skladištenje je bilo na sobnoj temperaturi, za seme iz 2018. godine, a u cilju smanjenja broja enterobakterija i ukupnog broja mikroorganizama. Pri skladištenju semena iz 2018. godine u cilju smanjenja broja plesni i kvasaca primećen je nešto manji broj datih mikroorganizama kada je seme čuvano u vakuumski zatvorenoj vrećici, na temperaturi frižidera/zamrzivača. Za seme konoplje iz 2019. godine najoptimalniji uslovi skladištenja su bili na temperaturi frižidera (za redukciju broja enterobakterija) i u zamrzivaču (za redukciju ukupnog broja mikroorganizama). Za smanjenje ukupnog broja plesni i kvasaca, optimalni uslovi su bili na sobnoj temperaturi. Etanol (75%, v/v) je bio najefikasnije sredstvo za dezinfekciju među ispitivanim hemijskim sredstvima, bez obzira na početni broj mikroorganizama, sa log smanjenjem od 3,2 (za ukupan broj enterobakterija), 2,9 log (za ukupan broj mikroorganizama) i ukupnim smanjenjem broja kvasaca i plesni nakon 10 minuta delovanja, za seme proizvedeno 2019. godine, koje je bilo mnogo više kontaminirano u odnosu na seme iz 2018. godine. Uzimajući u obzir cenu metoda dezinfekcije etanolom, natrijum hipohlorit može biti bolje rešenje za smanjenje broja mikrobiota na semenu.

This research examined in vitro probiotic potential of Lactobacillus curvatus isolates from fermented sausage originating in Southeast Serbia which was prepared using traditional production techniques. Strains of L. curvatus were isolated and identified at the level of species using API 50CHL sets and 16s rDNA sequencing, after which their probiotic potential was measured. The research consisted of the examination of isolate survival rates in the gastrointestinal tract, synthesis of biogenic amines, the growth on the media with different quantities of phenol, antibiotic resistance test, and antimicrobial activity against clinical strains of Pseudomonas spp., Proteus spp., Enterobacter spp., Escherichia coli and Listeria monocytogenes. The examined isolates have shown a good survival rate at low pH in the simulated stomach and small intestine conditions. Synthesis of biogenic amines was exhibited by the isolate sk1-10, which had a positive reaction to histidine. Analyzed isolates grew well on media with 0.1% and 0.2% of phenol, L.curvatus sk1-8 and sk5-2 have grown in media with 0.3% phenol. All tested isolates have exhibited high sensitivity to most analyzed antibiotics (tetracycline, amoxicillin, ceftriaxone, erythromycin, penicillin), resistance to ofloxacin, and cephalexin isolates sk4-3a and sk4-15. The examined isolates have shown a broad inhibitory spectrum against pathogens.

This study investigates the effects of sodium nitrite replacement by the sage essential oil (SEO), on the physico-chemical, microbiological and sensory quality of dry fermented sausages (DFS) during 225 days of storage. The SEO (0.00, 0.05 and 0.10 µL/g) was added in DFS batters formulated with different levels of pork back fat (15% and 25%) and sodium nitrite (0, 75 and 150 mg/kg). The inclusion of SEO had no negative impact on pH, color (instrumental and sensory) and texture parameters. Total plate counts were lower than 6 log CFU (colony forming units)/g in all samples throughout the storage. Furthermore, the addition of SEO at concentration of 0.05 µL/g provided acceptable TBARS (2-Thiobarbituric acid reactive substances) values (&lt, 0.3 mg MDA (malondialdehyde)/kg) in the samples produced with reduced levels of sodium nitrite (0 and 75 mg/kg) without negative alternations on sensory attributes of odor and flavor. Generally, our findings confirmed that the usage of SEO could be a good solution to produce healthier DFS with reduced levels of sodium nitrite.

There has been a growing interest in traditional dairy (such as raw milk cheeses) and meat products, in recent years. However, these products are suitable and nutrient medium and may be easily contaminated by microorganisms such as Enterobacteriaceae. Enterobacteriaceae are considered to be the indicator bacteria for microbiological quality of food and hygiene status of a production process. Additionally, the food contaminated by Enterobacteriaceae poses a microbiological risk for consumers. In fact, the contamination of raw milk and meat by Enterobacteriaceae amid manufacturing may easily occur from various environmental sources, and this group of bacteria is frequently detected in dairy and meat products. Therefore, monitoring the microbiological quality of the used raw material and maintaining high standards of hygiene in the production process are mandatory for a high quality of traditional products and the safety of the potential consumers. The goal of this review is to present the most recent survey on Enterobacteriaceae growth, number, and distribution in raw milk cheeses and meat, as well as to discuss the sources of contamination and methods of control. • Enterobacteriaceae: role and importance in milk and meat products, EU legal regulations • Dynamics, distribution, and survival of Enterobacteriaceae in milk and meat • Mechanisms of control of Enterobacteriaceae in dairy products

The effect of Juniperus communis L. essential oil (JEO) addition at concentrations of 0.01, 0.05 and 0.10 &micro, L/g on pH, instrumental parameters of color, lipid oxidation (2-Thiobarbituric acid reactive substances (TBARS)), microbial growth, texture and sensory attributes of dry fermented sausages produced with different levels of fat (15 and 25%) and sodium nitrite (0, 75 and 150 mg/kg) was assessed. Reduced level of sodium nitrite (75 mg/kg) in combination with all three concentrations of JEO (0.01&ndash, 0.10 &micro, L/g) resulted in satisfying physico-chemical (color and texture) properties and improved oxidative stability (TBARS &lt, 0.3 mg MDA/kg) of dry fermented sausages produced with 25% of fat. However, sausages produced with 0.10 &micro, L/g of JEO had untypical flavor. No foodborne pathogens (Escherichia coli, Listeria monocytogenes, Salmonella spp. and sulfite-reducing clostridia) were detected in any sample throughout the storage period (225 days). The results of this study revealed significant antioxidative activity of JEO and consequently its high potential as effective partial replacement for sodium nitrite in dry fermented sausages.

The antioxidant and antimicrobial properties of Boletus edulis decoction and the effect of mushroom addition on the physicochemical and microbiological properties of frankfurters during refrigerated storage were studied. The addition of mushroom delayed the increase in the total number of aerobic mesophilic microorganisms during the storage. The incorporation of B. edulis in cooked sausages resulted in the significantly higher hardness of frankfurters in comparison with control, during chilled storage. Mushroom addition significantly affected the color of sausages throughout storage, but no deficiencies in sensory acceptance test were obtained. Generally, this mushroom can be used as a natural antioxidant to interfere with microorganism growth and extend the shelf life of cooked pork sausages during refrigerated storage. Practical applications In this study, the addition of B. edulis has proven to be a potent antioxidant and antimicrobial ingredient that extends the shelf life of frankfurters. That could be an interesting finding in potentially reducing or replacing commercial antioxidants with a natural, healthier variant of food additives.

Application of agro-industrial by-products for the production of lactic acid was studied in this paper. Brewer's spent grain (BSG), malt rootlets (MR), brewer's yeast (BY), and soy lecithin (SL) were used as raw materials in L-(+)-LA fermentation by free and immobilized Lactobacillus rhamnosus ATCC 7469. The BSG, solid remains after BSG and MR hydrolysis (BSGMRSR), and MR were evaluated as carriers for batch and repeated batch fermentations with immobilized cells. During batch fermentations with immobilized cells, high cell viability (10 to 11 log CFU/g) was achieved on all carriers. In batch fermentation with BSG as a carrier, the highest LA yield of 93.79% and volumetric productivity of 1.15 g/L/h were obtained. Furthermore, very high LA yield (95.46%), volumetric productivity (1.98 g/L/h) and L. rhamnosus viability (11.5 log CFU/g) were achieved in repeated batch fermentations with the cells immobilized on this carrier. The immobilized cells showed high survival rate (94-95%) during exposure to simulated gut condition. Based on the analysis of BSGMRSR, and BY solid remains, and on in vitro evaluation of the probiotic characteristics of immobilized cells, it was observed that they could satisfy the recommendations for high-quality feed preparation.

Stillage is a main by-product of the bioethanol industry and, depending on the origin of substrates for bioethanol production, it can be a significant pollutant affecting the profitability of bioethanol production. Directing the stillage towards the production of bio-based chemicals or high-quality feed is a preferred stra- tegy. In this paper, a complete utilization of stillages of different origins was assessed. Thin stillages from bioethanol production from molasses, wasted bread and corn were chemically characterized, evaluated and compared as substrates for lactic acid (LA) and probiotic biomass production by Lactobacil- lus rhamnosus ATCC 7469, while solid fractions of wasted bread and corn stil- lages were analyzed for feed. The impact of pH control using CaCO 3 or NaOH was also examined, both in terms of LA production and valorization of the remains generated in each process.A maximal LA productivity of 1.14 g/(L h) was obtained on thin wasted bread stillage with pH control by NaOH while the number of viable probiotic bacterial cells was above 109 CFU/mL. The com- position of the solid fraction of the wasted bread stillage was complementary with the needs of monogastric animals, while the solid fraction of corn stillage was more adequate for the nutritional requirements of ruminants. Džibra je najznačajniji otpadni ili sporedni proizvod industrije bioetanola. U zavisnosti od porekla supstrata koji se koriste u proizvodnji bioetanola, može biti značajan zagađivač, pa utiče na profitabilnost proizvodnje bioetanola. Upotreba džibre u biotehnološkim postupcima proizvodnje hemikalija ili visoko vredne stočne hrane je poželjna strategija za smanjenje negativnih efekata džibre na životnu sredinu i profitabilnost proizvodn je bioetanola. U ovom radu je analizirana mogućnost kompletnog iskorišćenja džibre. Tečne džibre iz proizvodnje bioetanola na melasi, otpadnom hlebu i kukuruzu su hemijski okarakterisane i upoređene kao supstrati za proizvodnju mlečne kiseline (MK) i probiotske biomase soja Lactobacillus rhamnosus ATCC 7469, dok je čvrsti ostatak hlebne i kukuruzne džibre analiziran kao hrana za životinje. Takođe je ispitan uticaj pH kontrole pomoću CaCO3 ili NaOH sa aspekta proizvodnje MK i sa aspekta iskorišćenja ostataka iz oba procesa. Maksimalna produktivnost MK od 1,14 g/(L h) je dobijena na tečnoj džibri iz otpadnog hleba sa pH kontorolom pomoću NaOH, dok je broj živih pro- biotskih bakterija bio preko 10 9 CFU/mL. Rezultati su pokazali da je sastav čvrste frak- cije otpadne hlebne džibre komplementaran sa potrebama monogastričnih životinja, dok sastav čvrste frakcije kukuruzne džibre više odgovara nutritivnim potrebama preživara.

The effect of sage essential oil (SEO) and sage extract (SE) obtained from sage (Salvia officinalis L.) herbal dust (food industry by-product) on microbiological and oxidative stability of fresh pork sausages was investigated. pH, microbiological analysis, TBARS value and sensory panel scores were assessed. Oxygenated monoterpenes, oxygenated sesquiterpenes and diterpene polyphenols were the most abundant compounds present in SEO and SE samples. SEO and SE addition resulted in significant (p

Research Areas: Food Science & Technology This research aimed to investigate and compare traditional products called “duvan chvarci” produced using pork meat and fat, originated from local households and industries. Physical and chemical analysis demonstrated differences among the examined products, mostly in total chloride content and TBARS values. Samples collected at local households showed finer color (higher lightness and yellowness) and sensory properties (rated as “extremely acceptable”), while industrial products were rated between “very acceptable” and “extremely acceptable“. Microbiological analysis exhibited that enterobacteria, coagulase-positive staphylococci, Salmonella spp., Shigella spp., and fungi were absent from all meat products. Dominant microbiota was identified as Lactobacillus spp. and Staphylococcus spp. All tested isolates showed γ-haemolysis on blood agar plates. Tested Staphylococcus spp. were sensitive to novobiocin while Lactobacillus isolates demonstrated sensitivity to ampicillin, chloramphenicol, clindamycin, erythromycin, tetracycline, gentamycin, and streptomycin. None of the tested isolates showed full resistance to antibiotics. Overall, results indicated that duvan chvarci is a microbiologically safe product and provided the initial evidence regarding the physical, chemical, technological, and sensory properties of this widely consumed product in the Balkans. info:eu-repo/semantics/publishedVersion

A serious global problem with the increasing resistance of microorganisms to currently used antimicrobials has opened up the promotional research in the identification of new, more effective drugs with a broad spectrum of antimicrobial activities. Plant essential oils, due to the large biological and structural diversity of their components, are known to have many potential benefits. This study aimed to evaluate the antimicrobial and anti-adhesion activity of fifteen essential oils and their compounds against two bacterial and two yeast species responsible for food spoilage and infectious diseases. Antimicrobial activity was determined by testing the minimum inhibitory concentration (MIC), the minimum bactericidal concentration (MBC) and the minimum fungicidal concentration (MFC) of essential oils and compounds. The essential oils of Cinnamomum zeylanicum and Eugenia caryophyllus showed the highest antimicrobial activity with MICs ranging from 0.078 to 1.25 mg/mL, and 0.039 to 1.25 mg/mL, respectively. On the other hand, essential oils of Eucalypti aetheroleum and Salvia officinalis had significantly weaker antimicrobial properties than the others. Further, MICs were used to assess the inhibition of adhesion of bacteria Salmonella Typhimurium ATCC 25923 and Staphylococcus aureus ATCC 14208, and yeasts Candida albicans ATCC 10231 and Saccharomyces cerevisiae ATCC 9763 in a microtiter plate using the crystal violet staining method. Based on the percentage of adhesion inhibition, yeast S. cerevisiae ATCC 9763 showed a high level of antimicrobial resistance. E. caryophyllus had the strongest effect with inhibition up to 73%. Consistent with the antimicrobial susceptibility results, the most active anti-adhesion compounds were carvacrol and thymol. Considering the role of biofilm in food spoilage and clinical diseases, inhibition of the initial phase of biofilm formation by natural antimicrobial agents may be an alternative to commonly used synthetic ones.

Brewer's spent grain (BSG) hydrolysates were used for l-(+)-lactic acid (LA) fermentation by Lactobacillus rhamnosus ATCC 7469. The aim of this study was to evaluate fed-batch LA fermentation of BSG hydrolysate with the addition of glucose, glucose and yeast extract, and wort during LA fermentation and its effect on fermentation parameters such as LA concentration, its volumetric productivity and yield, and L. rhamnosus cell viability. The highest LA yield, volumetric productivity and concentration of 93.3%, 2.0 g/L/h, and 116.1 g/L, respectively, were achieved with glucose and yeast extract addition during fermentation. In fed-batch fermentation with glucose and yeast extract addition significantly higher LA concentration, yield and volumetric productivity (by 194.8; 2.2, and 20.7%, respectively) were achieved compared with batch fermentation. The results indicated that fed-batch fermentation could be used to increase LA fermentation efficiency. Copyright © 2017 The Institute of Brewing & Distilling

The objectives of this research project were isolation, identification, and evaluation of the safety aspect and probiotics properties of 21 Enterococcus faecium strains isolated from sausages originated from southeastern Serbia. Analyzed E. faecium isolates showed tolerance to simulated gastrointestinal conditions. All the examined isolates grew well on media with 0.1% and 0.2% of phenol. None of the tested isolates were histamine-producers, while the synthesis of tyramine was observed for E. faecium sk8-1 and sk8-17. Full resistance to antibiotics was not observed for any examined isolate of E. faecium (penicillin, amoxicillin, and ofloxacin showed the effect on all tested isolates). An inhibition zone against examined pathogens was exhibited by all strains, with the largest inhibition zone against Pseudomonas spp., Proteus spp. and E. coli (12–30 mm/MIC values ranged from 0.5 to 12 mg mL−1). The results indicated that E. faecium isolates from spontaneously fermented sausage showed a potential for further investigation and possible application as probiotics.

The effects of wild thyme by-products (Thymus serpyllum L.) from supercritical fluid extraction SFE1 (100 bar and 40 °C) and SFE2 (350 bar and 50 °C) on the quality of ground pork patties evaluated by pH, CIE-color, lipid (TBARS test) and protein oxidation (thiol group content) and microbiological profile. SFE extracts were added to ground pork patties as: 0.075 μL/g of SFE1 (T1), 0.150 μL/g of SFE1 (T2), 0.075 μL/g of SFE2 (T3), 0.150 μL/g of SFE2 (T4), while SFEs (T5) was control without any extracts. SFE1 and SFE2 were protective against color degradation. Moreover, the addition of SFE1 and SFE2 significantly reduced lipid and protein oxidation in the patties (p ≤ 0.05). Furthermore, lower concentration of SFE2 reduced total plate count to

BACKGROUND Brewer's spent grain (BSG), brewer's yeast (BY), malt rootlets (MR), and soy lecithin (SL) are valuable and abundant by-products obtained from brewing, malting, and oil industry, respectively. L-(+)-lactic acid (LA) is organic acid that has a wide range of application. In this study hydrolysate obtained from BSG and MR mixture (BSGMR), was used in combination with SL and BY extract (BYE) in LA fermentation. The aim was to evaluate the effect and to optimize the addition of SL (0.1% and 0.2%) or BYE (10% and 20%) compared with Tween 80 (0.1%) and yeast extract (0.8%), in batch and fed-batch LA fermentation. RESULTS Using optimal SL and BYE concentrations (0.19% and 19.12%, respectively) obtained by response surface methodology (RSM), the highest LA concentration, yield, and volumetric productivity of 28.43 g L-1, 93.03%, and 1.04 g L-1 h(-1), respectively, were achieved in batch fermentation, with further increase using fed-batch fermentation (70.17 g L-1, 94.57%, and 1.22 g L-1 h(-1), respectively). CONCLUSION The results achieved indicated that the combination of industrial by-products, BSG, MR, SL, and BYE can be used as very suitable fermentation media for LA production, and that SL and BYE could be used as cheap replacements for Tween 80 and YE without decreasing fermentation efficiency. This is the peer-reviewed version of the following article: Radosavljević M, Pejin J, Pribić M, Kocić-Tanackov S, Mladenović D, Đukić-Vuković A, Mojović L. Brewing and Malting Technology By-Products as Raw Materials in L-(+)-Lactic Acid Fermentation. in Journal of Chemical Technology and Biotechnology. 2020;95(2):339-347. [https://doi.org/10.1002/jctb.5878] Published version: [https://technorep.tmf.bg.ac.rs/handle/123456789/4354]

Inhibitory activity of caraway and juniper essential oils was tested against two aflatoxigenic strains (Aspergillus flavus-four isolates and Aspergillus parasiticus-one isolate) using the method of agar plates. A. flavus IKBT and A. flavus IKB isolated from corn flour, A. flavus IKT isolated from peanuts, and A. flavus IKK isolated from flint corn. A. parasiticus CBS 260.67 was obtained from the Centralbureau voor Schimmelcultures (CBS, Utrecht, The Netherlands). The inhibitory effect of essential oils on aflatoxins secretion by A. flavus (isolated from maize flour) was examined in the polenta. Growth of all fungi were completely inhibited at caraway essential oil concentration of 4.5 mu l/g. At this concentration, aflatoxin secretion was completely inhibited in polenta. Juniper essential oil particularly inhibited growth of examined fungi at the applied concentration of 35 mu l/g (from 42.4% to 79.7%). At concentration of 50.0 mu l/g, this oil completely inhibited aflatoxin secretion in polenta. Practical applications The obtained results show that caraway essential oil had significantly better inhibitory effects against A. flavus, A. parasiticus, and aflatoxins production than juniper essential oil, in vitro and in polenta. Future research should point to the possible application of this oil in different types of food and the choice of an efficient method: adding them directly to the product, surface coating of the products, dispersing, applying them in the atmosphere of the package, coating the inner side of the packaging, applying in edible films, or in the form of nanocapsules. In the case of polenta, essential oils can be applied in the packaging atmosphere, by coating the inside of the package, or adding them directly to the polenta.

Brewer's spent grain (BSG) is a by-product generated during the brewing process. It is a rich source of dietary fibre and proteins, with great potential to increase nutritional value of food products. In this research different quantities of fresh (non-dried and non-milled) brewer's spent grain (15, 25 and 50%) were added to wheat flour on a replacement basis in order to evaluate its effect on fibre and protein content, instrumental parameters of colour, microbial stability and sensory characteristics of cookies. Protein and fibre content of cookies increased following the addition of BSG from 7.55% to 9.69% and 6.8 to 15.55%, respectively. Considering the colour characteristics, addition of BSG decreased L*and b* values, while a*values increased. Enterobacteriaceae, Escherichia coli, Clostridium spp., yeasts and moulds were not detected in cookie samples, while the Enterobacteriaceae were detected (40 cfu/g) in fresh BSG. The addition of 25% of BSG resulted in best sensory characteristics of cookies in terms of surface appearance, hardness, grittiness and flavour. The results have shown that fresh BSG has a potential to increase nutritional value of the cookies without negative influence on cookie sensory characteristics and microbiological stability.

Concentrations of cadmium (Cd) and lead (Pb) were determined in livers (n = 52) and kidneys (n = 52) of female cattle (345–2717 days old) from dairy farms in the region Vojvodina. Cd and Pb were analysed by inductively coupled plasma-optical emission spectrometry, after microwave digestion. Cd and Pb concentrations did not exceed the Serbian and European maximum set limits in any sample. The Cd concentrations in the livers and kidneys ranged from 0.033 to 0.151 mg kg−1 wet weight and from 0.055 to 0.510 mg kg−1 wet weight, respectively. The corresponding Pb concentrations were 0.015-0.159 mg kg−1 wet weight and 0.021-0.196 mg kg−1 wet weight, respectively. Mean Cd and Pb concentrations were significantly lower (p

The effect of supercritical fluid extract of tomato pomace (TP) and essential oil of organic peppermint (PM) on pH, color, residual nitrite content, lipid oxidation (TBARS value) and total plate count (TPC) of cooked pork sausages produced with 50 mg/kg of sodium nitrite was investigated. Five batches were produced: T1: 100 mg/kg of sodium nitrite; T2: 50 mg of sodium nitrite; T3: 50 mg of sodium nitrite and 0.150 µL/g TP; T4: 50 mg of sodium nitrite, 0.075 µL/g TP and 0.075 µL/g PM; T5: 50 mg of sodium nitrite and 0.150 µL/g PM. The lowest residual nitrite content and TBARS value were observed in treatment T4. The inclusion of TP increased redness of cooked pork sausages. TPC was the lowest in treatment T5. The results of this study showed that the addition of TP and PM enhanced quality of cooked sausages produced with reduced level of sodium nitrite.

Food contamination by molds is a serious issue in food industry still today. On the other hand, consumers today demand food that is minimally processed and without synthetic preservatives and additives. Therefore, the objective of this paper was to examine the antifungal effect basil and caraway essential oils (EOs) against Penicillium aurantiogriseum FEMK1, P. carneum FEMK2, P. cavernicola FEMK3, P. nalgiovense FEMK4, P. polonicum FEMK5, and Mucor racemosus FEMK6, isolated from the surface of fermented sausages, in vitro and in vivo.Caraway EO showed better antifungal effects in vitro than basil EO. Minimal fungicidal concentration (MFC) of caraway EO for P. aurantiogriseum FEMK1 was 1.5 μl/mL, and for other species 4.5 μl/mL, while MFC of basil EO was 9.0 μl/mL for P. aurantiogriseum FEMK1, P. carneum FEMK2, P. cavernicola FEMK3, and M. racemosus FEMK6. Applied EOs caused macro- and micromorphological changes in the examined molds. EOs applied to the surface of fermented sausage that was artificially inoculated with conidia suspension of P. carneum FEMK2 and P. polonicum FEMK5, has significantly affected the reduction of molds growth. The results obtained in this investigation indicate to possibility of applying EOs in the antifungal protection of fermented sausages.

The effect of coriander essential oil (CEO) at concentrations of 0.075–0.150 μL/g on pH, color, lipid oxidation (TBARS), residual nitrite concentration and microbial growth of cooked pork sausages produced with different levels of sodium nitrite (0, 50 and 100 mg/kg) was investigated. Artificial neural networks modeling and the multi-response optimization were used to determine the optimal combinations of process parameters and storage time. Reduced concentration of sodium nitrite (60 mg/kg) in combination with 0.12 μL/g of CEO resulted in satisfying redness ( a* approx. 11.1) and improved oxidative (TBARS approx. 0.12 mg MDA/kg) and microbial stability (total plate count – TPC approx. 2.50 Log CFU/g) of cooked pork sausages during refrigerated storage. Therefore, the results of this paper revealed significant antioxidative and antimicrobial activity of CEO, and consequently its high potential of utilization in processing of cooked pork sausages with enhanced quality and shelf-life.

The effect of winter savory (Satureja montana L.) essential oil (SEO) and supercritical extracts (SE1; SE2) at concentrations of 0.075 and 0.150 µL/g on pH, lipid oxidation (TBARS), microbial growth and sensory quality of fresh pork sausages during storage were investigated. SEO, SE1 and SE2 improved oxidative and microbial stability of fresh pork sausages. The addition of SEO and SE1 at concentration of 0.150 µL/g affected the reduction of total Enterobacteriaeceae count to under 3 log cfu/g. Sausages produced with SE1 and SE2 had a higher scores for odor, flavor and overall acceptance compared to sausages treated with SEO and control sample. Therefore, the results of this paper revealed significant antioxidative and antimicrobial activity of SE1 and SE2, and consequently its high potential of utilization in processing of fresh pork sausages.