Effect of glycerol content and pH value of film-forming solution on the functional properties of protein-based edible films

The work is concerned with the effects of glycerol content and pH value of film forming solution on the functional properties of protein-based films. The films were produced of chicken breast proteins, dissolved under either acidic (pH 3) or alkaline (pH 11) conditions, with different concentrations of glycerol (35%, 50% and 65% w/w of protein content). Glycerol content affected significantly mechanical properties, water vapor permeability, color at pH 3 and film solubility (p<0.05). The pH value had significant influence on light transmission, color, transparency and film solubility (p<0.05). Considering the results of mechanical properties and film solubility, the obtained films are in the acceptable range for the use as a packaging material. It was estimated that water vapor permeability, color, light transmission and transparency need to be improved for the application

Air mycopopulations in Petrovská klobása producing facility

Different types of filamentous fungi periodically cause problems in small-scale facilities for traditional dry fermented sausages, such as Petrovská klobása from Vojvodina province (Serbia). Mould contamination can be observed during processing, ripening, and storage. Sausages may become spoiled due to visible mould colonies on the surface and off-flavours they produce. The most important - if mycotoxin production occurs it might promote a number of health disorders. Knowledge and control of filamentous fungi are, therefore, essential to produce sausages that satisfy the criteria of hygienic quality, sensorial characteristics, and food safety. The aim of this study was to survey mycoflora of a small-scale facility producing traditional dry fermented sausage - Petrovská klobása. The mould contamination of the air in processing unit and ripening chambers was investigated, in order to determine the important fungi in terms of spoilage of the products and ability to produce mycotoxins. The mould contamination of air in processing unit and ripening chambers examined was in range 0.22 - 1.89 log CFU/P.d. Isolated moulds belong to 6 genera: Aspergillus (3 species), Cladosporium (1 species), Eurotium (2 species), Fusarium (1 species), Penicillium (12 species) and Scopulariopsis (1 species). The most abundant were species of Penicillium genus, many of which are capable for mycotoxin production. The level and diversity of fungal contamination of air varied between samples, influenced by the general hygiene, the buildings, the airflow, the outdoor environments, and the time of year. This knowledge is crucial for the improvement of hygiene control systems in small-scale processing units

Mycopopulations and ochratoxin A: Potential contaminants of Petrovská klobása

Petrovská klobása is traditionally produced dry fermented sausage from the area of Bački Petrovac (Vojvodina Province, Serbia) that has been protected with designation of origin (PDO) according to Serbian legislation. Contamination of this kind of sausage casings by different mould species often occur during the production process, mainly during the ripening and storage. The aim of this study was to isolate and identify moulds that contaminate ingredients used for Petrovská klobása production and its casings during different phases of ripening and storage. Sampling was done during the production process and after 2, 6, 9, 11, 14, 34, 65, 90, 120, 217 and 270 days. Total mould counts in components ranged from 1.60 (mechanically mixed filling) to 4.14 (red hot paprika powder) log10 CFU/g, while the number of moulds isolated from sausage casing surfaces ranged from 0.01 (C3 sausage, 217th day) to 1.60 (C1 sausage, 270th day) log10 CFU/cm2. After total mould counts were determined, isolates were identified and classified in five genera for components (Penicillium - 7 species; Fusarium - 2 species; Aspergillus - 1 species; Alternaria - 1 species; Verticilium - 1 species) and 3 genera for casings surfaces (Penicllium - 3 species; Aspergillus - 1 species; Eurotium - 1 species). It was appointed that 83.33% of isolated species are potential producers of toxic metabolites. The analyses of ingredients and sausages on the presence of ochratoxin A, following the ELISA method, gave the negative results

Kserofilne mikopopulacije izolovane iz semena uljane repice

This paper presents the results of an investigation related to mycological populations of rapeseed samples produced in the Institute of Field and Vegetable Crops in Novi Sad (location: Rimski Šančevi, Novi Sad), with a special emphasis on the potentially toxigenic mycopopulations. Mycological investigations were performed on the samples that were treated with 4% solution of Na-hypochlorite, and on the ones that were not submitted to this treatment. Isolation and determination of total mould count was carried out using Dichloran Glycerol Agar (DG18). The identification of isolated moulds was done according to modern keys for fungal determination. From 20 untreated tested samples, 17 were contaminated with moulds (10.0 to 4.7x102 cfu/g). When the samples were treated with 4% solution of Na-hypochlorite, moulds were isolated only form 4 samples, and the total mould count ranged from 10.0 to 60.0 cfu/g. In the isolated mycopopulations, xerophilic moulds dominated, especially those from the genera Aspergillus, Eurotium and Penicillium. In the isolated mycopopulations, high degree of isolated species belonged to toxigenic species from the genera Alternaria, Aspergillus, Fusarium, Eurotium and Penicillium.U radu su data istraživanja vezana za mikološku populaciju u uzorcima uljane repice proizvedene u Institutu za ratarstvo i povrtarstvo (lokacija Rimski Šančevi, Novi Sad), sa posebnim osvrtom na potencijalno toksigenu mikopopulaciju. Mikološka ispitivanja su izvedena u uzorcima koji su tretirani sa Na-hipohloritom, kao i u uzorcima koji nisu podvrgnuti ovom tretmanu. Izolacija i određivanje ukupnog broja plesni izvedeno je na Dixloran Glicerol agaru. Identifikacija izolovanih vrsta plesni izvedena je prema ključevima za determinaciju koji su opisani u literaturi. Od 20 ispitanih uzoraka u 17 je utvrđeno prisustvo plesni i ukupan broj se kretao do 10 do 4,7x102 cfu/g. Kada su uzorci tretirani 4% rastvorom Na-hipohlorita plesni su izolovane iz 4 uzorka, a ukupni broj plesni se kretao od 10,0 do 60,0 cfu/g. U izolovanoj mikopopulaciji dominirale su kserofilne vrste iz rodova Aspergillus, Eurotium i Penicillium. Izolovanu mikopopulaciju u visokom procentu činile se potencijalne toksigene vrste iz rodova Alternaria, Aspergillus, Fusarium, Eurotium i Penicillium

Božo Milošević's sociological themes in Sociološki pregled / Sociological Review

The authors point to the contribution of Božo Milošević's to Serbian sociological thought, through his scientific papers published in the journal Sociološki pregled/Sociological Review, since the end of the 1980s until today. His contribution is mostly reflected in the advancement of the theoretical foundations of the Sociology of Work, without neglecting any other sociological topics necessary for essential understanding of contemporary social processes and relations

Sunflower seed for human consumption as a substrate for the growth of mycopopulations

These mycological investigations are implicating samples of protein sunflower seed from regular cultivation in the Vojvodina Province. Samples are examined in different stages of production: reception in the silo, separation of massive fraction on peeler and then peeling, kernel after peeling, hull, final product, i.e. kernels separated from visible impurities on conveyor bel, that are later manually divided in two fractions - a) seemingly whole, undamaged kernels, without change of colour, and b) seemingly damaged kernels, broken, with change of colour. For the determination of viable count of moulds and their isolation, two different media are used in parallel: Sabouraud maltose agar (SMA) and malt/yeast extract with 50% of glucose (MY50G), favourable for growth of xerophilic moulds. All samples tested were contaminated with fungi. Total viable mould count per seed varied from 1.6 (SMA) respecting 1.3 (MY50G) on reception, to 5.6 (SMA) and 7.5 (MY50G) cfu/seed in visually damaged sunflower kernels (final product). From seeds, kernels and hull, numerous moulds were isolated, belonging to 8 genera and 13 species (Alternaria alternata, Arthrinium phaeospermum, Aspergillus candidus, A. flavus, A. niger, A. ochraceus, A. versicolor, A. wentii, Cladosporium cladosporioides, Eurotium herbariorum, Penicillium aurantiogriseum, Rhizopus stolonifer and Trichoderma harzianum). Alternaria alternata, Aspergillus flavus, A.ochraceus, A. versicolor and Eurotium herbariorum were isolated on both media. Aspergillus candidus, A. versicolor, C. Cladosporioides, P. aurantiogriseum and T. harzianum were isolated only on SMA, while A. niger, A. wentii and R. stolonifer were exclusively isolated on MY50G. Most ubiquitous species is A. alternata, which is isolated from all tested samples, while A. candidus, C. cladosporioides and T. harzianum were isolated from sunflower seed on reception in silo, using SMA medium

Identification of aflatoxigenic fungi using polymerase chain reaction-based assay

As the aflatoxins represent a health-risk for humans because of their proven carcinogenicity, food-borne fungi that produce them as secondary metabolites, mainly Aspergillus flavus and Aspergillus parasiticus, have to be isolated and identified. The best argument for identifying problem fungi is that it indicates control points within the food system as part of a hazard analysis critical control point (HACCP) approach. This assumes there is a close link between fungus and toxin. Conventional methods for isolation and identification of fungi are time consuming and require admirably dedicated taxonomists. Hence, it is imperative to develop methodologies that are relatively rapid, highly specific and as an alternative to the existing methods. The polymerase chain reaction (PCR) facilitates the in vitro amplification of the target sequence. The main advantages of PCR is that organisms need not be cultured, at least not for a long time, prior to their detection, target DNA can be detected even in a complex mixture, no radioactive probes are required, it is rapid, sensitive and highly versatile. The gene afl-2 has been isolated and shown to regulate aflatoxin biosynthesis in A. flavus. Also, the PCR reaction was targeted against aflatoxin synthesis regulatory gene (aflR1) since these genes are nearly identical in A. flavus and A. parasiticus in order to indicate the possibility of detection of both the species with the same PCR system (primers/reaction). [Projekat Ministarstva nauke Republike Srbije, br. III46009

Antifungal activity of Oleoresins used in meat industry on some toxigenic Aspergillus spp.

Different spice oleoresins are widely used in meat industry. They contribute to the specific aroma and flavor of the end products, but they have also been reported to have strong antimicrobial activity. These properties open a plenty of possibilities to be used for defining the specific sensory profile of the product but also as natural food preservatives. This paper focuses on the antifungal activity of four oleoresins against different foodborne toxigenic Aspergillus species. Oleoresins used in the experiments were cayenne pepper, black pepper, garlic and rosemary oleoresins, and they were tested against following Aspergillus species: A. clavatus, A. flavus, A. fumigatus, A. niger, A. ochraceus and A. versicolor. Antifungal activity was tested using microtitre-plate-based assay incorporating resazurin as an indicator of cell growth and broth microdilution-method. [Projekat Ministarstva nauke Republike Srbije, br. III46009

Review of the occurrence of ochratoxigenic fungal species and ochratoxin A in some agricultural products

Ochratoxin A (OTA) is one of the most important and widespread fungal toxic metabolites, which has been detected in our country for years in feed and food, mostly originated from plants. It is a very important contaminant of the plant food commodities in nephropathic areas of the Balkan and Mediterranean countries, but also in other countries in Europe and worldwide. This paper reviews the occurrence of OTA-producing fungi and OTA in some agricultural products (fresh fruits, dried fruits, fruit juices and other fruit products, vegetable products, wine, vinegar, cereals, mill products, etc.

Mineral concentration of the kidney in ten different pig genetic lines from Vojvodina (northern Serbia)

Concentration of phosphorous (P), potassium (K), sodium (Na), magnesium (Mg), calcium (Ca), iron (Fe), zinc (Zn), copper (Cu), and manganese (Mn) was determined in the kidney tissue of sixty-nine pigs belonging to ten different genetic lines of pigs, produced in Vojvodina (northern Serbia). Phosphorous was determined by the standard spectrophotometric method. Metals were determined by the flame atomic absorption spectrometry after mineralization by dry ashing. The order of the minerals in the kidney tissue and their content ranges in mg/100 g was P (246–347, on average 287) > K (142–236, on average 189) > Na (102–187, on average 130) > Mg (17.8–36.6, on average 23.3) > Ca (15.9–27.7, on average 20.2) > Fe (5.32–10.42, on average 7.42) > Zn (2.15–4.10, on average 2.99) > Cu (0.62–2.15, on average 1.29) > Mn (0.16–0.30, on average 0.22). Genetic lines of pigs had no influence on mineral concentrations of kidney (P>0.05). The Vojvodian pig kidney showed slightly lower K, slightly higher P and Mn, and higher Ca contents, compared to the values reported in the literature