Radmilo Čolović

Possibility of Alternaria toxins reduction by extrusion processing of whole wheat flour.

This study represents the first report about possibility of reduction of Alternaria toxins in wheat using the extrusion process. Effects of extrusion processing parameters - moisture content (w=16, 20, 24g/100g), feeding rate (q=15, 20, 25kg/h), and screw speed (v=300, 390, 480rpm), on reduction rate of tenuazonic acid (TeA), alternariol (AOH) and alternariol monomethyl ether (AME), in whole wheat flour were investigated. Temperature ranged between 111.1 and 160.8°C, while the absolute pressure was from 0.17 to 0.23MPa. The simultaneous influence of w and v was the most important for TeA reduction (p<0.05), while v and q were the most influential for AOH reduction (p<0.01). Level of AME reduction was mostly influenced by w and v (p<0.10). Optimal parameters for reduction of all three Alternaria toxins were as follows: w=24g/100g, q=25kg/h, v=390rpm, with a reduction of 65.6% for TeA, 87.9% for AOH and 94.5% for AME.

Beneficial properties of probiotic yeast Saccharomyces boulardii

Saccharomyces boulardii is unique probiotic and biotherapeutic yeast, known to survive in gastric acidity and it is not adversely affected or inhibited by antibiotics or does not alter or adversely affect the normal microbiota. S. boulardii has been utilized worldwide as a probiotic supplement to support gastrointestinal health. The multiple mechanisms of action of S. boulardii and its properties may explain its efficacy and beneficial effects in acute and chronic gastrointestinal diseases that have been confirmed by clinical trials. Caution should be taken in patients with risk factors for adverse events. Its potential application in various dairy foods could offer an alternative probiotic product to people suffering from antibiotic‐associated diarrhea. This review discusses the evidence for efficacy and safety of S. boulardii as a probiotic for the prevention and therapy of gastrointestinal disorders in

A New Concept to Secure Food Safety Standards against Fusarium Species and Aspergillus Flavus and Their Toxins in Maize

Commercial maize hybrids are exposed to different degrees of ear infection by toxigenic fungal species and toxin contamination. Their resistance to different fungi and toxin relationships are largely unknown. Without this knowledge, screening and breeding are not possible for these pathogens. Seven- to tenfold differences were found in resistance to Fusarium spp., and there was a five-fold difference in ear coverage (%) in response to A. flavus. Three hybrids of the twenty entries had lower infection severity compared with the general means for toxigenic species. Three were highly susceptible to each, and 14 hybrids reacted differently to the different fungi. Differences were also observed in the toxin content. Again, three hybrids had lower toxin content in response to all toxigenic species, one had higher values for all, and 16 had variable resistance levels. Correlations between infection severity and deoxynivalenol (DON) content were 0.95 and 0.82 (p = 0.001) for F. graminearum and F. culmorum, respectively. For fumonisin and F. verticillioides ear rot, the Pearson correlation coefficient (r) was 0.45 (p = 0.05). Two independent isolates with different aggressiveness were used, and their mean X values better described the resistance levels. This increased the reliability of the data. With the introduction of this methodological concept (testing the resistance levels separately for different fungi and with two isolates independently), highly significant resistance differences were found. The resistance to different fungal species correlated only in certain cases; thus, each should be tested separately. This is very useful in registration tests and post-registration screening and breeding. This would allow a rapid increase in food and feed safety.

Aflatoxin, zearalenone, deoxynivalenol and fumonisin contamination of maize from the Autonomous Province of Vojvodina

Aflatoxins (AFs), fumonisins (FUMs), zearalenone (ZEA) and deoxynivalenol (DON) have been recognized as major contaminants of maize. Therefore, the presence of AFs, ZEA, DON and FUMs was examined in a total of 100 maize samples from the Autonomous Province of Vojvodina. Sample analyses were performed using the Enzyme Linked Immunisorbent Assay method. The results obtained indicate that 74 % of the maize samples were contaminated with FUMs (540.1-5076 μg/kg), followed by 52 % contaminated with DON (275.2-882.1 μg/kg), 15 % contaminated with ZEA (35.6-183.5 μg/kg) and 5 % contaminated with AFs (2.28-4.31 μg/kg). Although 78 % of the samples were contaminated with at least one mycotoxin, the concentration of FUMs exceed the maximum level (ML) proscribed by the Serbian regulations only in 4 % of the samples. Furthermore, the detected concentrations of AFs, ZEA and DON were in accordance with national regulations. This study is the first research of its kind on the presence of AFs, ZEA, DON and FUMs in maize harvested in the APV in 2016.

Influence of apple pomace inclusion on the process of animal feed pelleting

ABSTRACT Apple pomace (AP) is the main by-product of apple juice production. Large amounts of this material disposed into landfills can cause serious environmental problems. One of the solutions is to utilise AP as animal feed. The aim of this study was to investigate the impact of dried AP inclusion into model mixtures made from conventional feedstuffs on pellet quality and pellet press performance. Three model mixtures, with different ratios of maize, sunflower meal and AP, were pelleted. Response surface methodology (RSM) was applied when designing the experiment. The simultaneous and interactive effects of apple pomace share (APS) in the mixtures, die thickness (DT) of the pellet press and initial moisture content of the mixtures (M), on pellet quality and production parameters were investigated. Principal component analysis (PCA) and standard score (SS) analysis were applied for comprehensive analysis of the experimental data. The increase in APS led to an improvement of pellet quality parameters: pellet durability index (PDI), hardness (H) and proportion of fines in pellets. The increase in DT and M resulted in pellet quality improvement. The increase in DT and APS resulted in higher energy consumption of the pellet press. APS was the most influential variable for PDI and H calculation, while APS and DT were the most influential variables in the calculation of pellet press energy consumption. PCA showed that the first two principal components could be considered sufficient for data representation. In conclusion, addition of dried AP to feed model mixtures significantly improved the quality of the pellets.

A survey on the potential research and development tendency in the Italian and Serbian feed industry = Anketa o potencijalnim tendencijama vezanim za istraživanje i razvoj u kompanijama za proizvodnju hrane za životinje iz Italije i Srbije

This study investigates potential areas for research and development in the feed sectors in Italy and Serbia. A questionnaire was submitted to 113 feed companies, 37% of these answered. Frequency statistics, data graphs and Simple Correspondence Analysis was obtained. Results indicated that 7% of responders in Italy and 47% of Serbia have not planned any budged for research and development in the last 3 years. The industrial processes were the main focus for Italy, while new product developments for Serbia. For both countries will be essential in the near future increase in product quality, search for new markets and reduction of energy consumption. Additionally, it was observed that company dimension is linked to the area/focus of innovation, irrespective of the type of feed production.

Fatty acid composition and natural antioxidant capacity of ten Serbian linseed cultivars

Literature data about nutritional characteristics of linseed cultivars from some specific geographical area or country is scarce. For that very reason, following paper is presenting fatty acid (FA) compositions and antioxidant capacity of lipid-soluble (ACL) components of ten native linseed cultivars from Serbia. These characteristics can be interesting, especially due to the increasing trend of linseed usage in human diet. Presented results show that there were statistically significant (p<0.05) differences between linseed kernels in FA composition. Negative correlation was found between FA C18:0 and α-linolenic acid (ALA). The cultivar with the highest ACL value was No. 10 (342.66 μmol trolox/kg d.m.), meaning that it had very strong protection against oxidation of polyunsaturated FAs. Nevertheless, correlation between ACL and polyunsaturated FA content in cultivars was not statistically significant (p=0.84). ACL of the samples did not depend on FA composition of linseed, but it might depend on characteristics of a specific cultivar. The aforementioned results show potential usage in storage of linseeds or its products, while FA composition of linseed kernels might be one of criteria for authentication of linseed origin, and can be of great help in future selection of the cultivars, depending on purpose of linseed production.

Use of different statistical approaches in prediction of metabolizable energy of diets for broilers

Energy value of diets has importance for feed producers and farmers. Methods for in vivo determination of metabolisable energy have high accuracy, but they are time and cost consuming. The aim of this study was to investigate the effect of enzymatic digestible organic matter and values of proximate chemical analysis on prediction of the nitrogen corrected true metabolisable energy (TMEn) of diets for broilers. The performance of Artificial Neural Network was compared with the performance of first order polynomial model, as well as with experimental data in order to develop rapid and accurate method for prediction of TMEn content. Analysis of variance and post-hoc Tukey‟s HSD test at 95% confidence limit have been calculated to show significant differences between different samples. Response Surface Method has been applied for evaluation of TMEn. First order polynomial model showed high coefficients of determination (r 2 = 0.859). Artificial Neural Network model also showed high prediction accuracy (r 2 = 0.992). Principal Component Analysis was successfully used in prediction of TMEn.

Pelleting properties and pellet quality of apple pomace

Apple pomace (AP) is the main by-product of apple juice production. It is a residue after pressing of apples for juice extraction. AP is an organic material, with high moisture and sugar content, therefore its direct disposal on landfills or land spreading causes serious environmental pollution. One of the solutions for further exploitation of AP could be its utilization as animal feed. However, fresh AP is quite perishable, and it must be preserved in order to be stored and used over a long period of time. The aim of this research was to investigate the possibility to transform AP to a stabile form which would be acceptable for feed manufacturers in terms of stability, storage and handling. For this purpose, pelleting process was used and pelleting properties of AP were evaluated. Before pelleting, dried AP was divided into three batches, which were conditioned only by water addition in order to achieve different moisture contents of the material: 10% of moisture for the first batch, 13% for the second batch and 16% for the third batch. According to the obtained values for Pellet Durability Index (PDI) and pellet hardness, pellet quality for all examined AP batches was very high. Increased moisture content of AP led to the reduction in energy consumption of the pellet press, thus providing energy saving in the pelleting process. Pelleting process also caused strong increase of AP bulk density which is positive in terms of transportation and storage.

Determining the degree of powder homogeneity using PC-based program

The mixing of powders and quality control of the obtained mixtures are critical operations involved in the processing of granular materials in chemical, metallurgical, food and pharmaceutical industries. Studies on mixing efficiency and the time needed for achieving homogeneity in the powder mashes production have significant importance. Depending on the characteristics of the materials, a number of methods have been used for the homogeneity tests. Very often, the degree of mixing has been determined by analyzing images of particle arrays in the sample using microscopy, photography and/or video tools. In this paper, a new PC-based method for determining the number of particles in the powder homogeneity tests has been developed. Microtracers®, red iron particles, were used as external tracers added before mixing. Iron particles in the samples of the mixtures were separated by rotary magnet and spread onto a filter paper. The filter paper was sprayed with 50% solution of ethanol for color development and the particles counted where the number of spots presented the concentration of added tracer. The number of spots was counted manually, as well as by the developed PC program. The program which analyzes scanned filter papers with spots is based on digital image analyses, where red spots were converted through few filters into a black and white, and counted. Results obtained by manual and PC counting were compared. A high correlation was established between the two counting methods.