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The influence of different extrusion parameters, including screw speed (250–750 rpm), feed rate (15–25 kg/h) and feed moisture content (15–25%), on the textural and color properties of spelt wholegrain snack products produced on a co-rotating twin-screw extruder with added betaine was investigated. In order to determine the relative influence of input variables in the artificial neural network (ANN) model, Yoon’s interpretation method was used, and it was concluded that feed moisture content has the greatest influence on L* values, while screw speed has the greatest influence on a* and b* values. The softest samples were obtained at the lowest moisture content. Sensory analysis was carried out on selected samples, and it showed that betaine addition did not intensify the bitter taste. The sample with the largest expansion exhibited the lowest hardness and chewiness before and after immersion in milk, and this sample is the most suitable for enrichment with betaine.

During previous years, regarding the shifts in climate conditions in temperate region, such as occurrence of high temperatures and prolonged drought, increased occurrence frequencies of Aspergillus flavus and aflatoxins in cereal grains were recorded. A reliable and accurate identification of the fungi is of great importance for evaluating the microbiological risks of contamination. The essential point of the present investigation was molecular characterisation and identification of A. flavus isolates originating from common wheat and spelt grains collected after harvest during the period of three years (2015–2017) in Northern Serbia. A holistic approach that included PCR amplification of two DNA genomic regions and PCR-RFLP assay followed by fragment length analysis, provided complete and comprehensive characterisation of A. flavus isolated from wheat grains. The presented results indicate that there was no difference among the tested Aspergillus isolates on the molecular–genetic level. All 38 strains were identified as A. flavus by sequencing of combined ITS region and β-tubulin gene fragments (acc. no.: MH582473 to MH582510). PCR-RFLP method in combination with a Lab-on-a-chip (LoaC) electrophoresis can be successfully used to rapidly identify A. flavus isolates.

The sugar industry is facing problems with high amount of molassigenic metal ions remained after the purification step in sugar juice. In this investigation the application of unmodified sugar beet pulp as a weak monofunctional cation-exchange biosorbent for molassigenic metal ions (Na+, K+ and Ca2+) removal from the alkalized sugar juice was studied. The batch biosorption experiments were performed at temperature (70 °C) and pH (10.5) of alkalized sugar juice similar to industrial conditions. The highest removal efficiency was noticed for divalent Ca2+ (30.2%), while monovalent Na+ and K+ ions were removed with 10.9 and 9.1% efficiency, respectively. Biosorption equilibrium was established in 90 min for all tested metals. Sugar beet pulp characterization from the perspective of cation-exhange material was conducted. The structure of the biosorbent and an insight of the functional groups were also characterized by scanning electron microscopy and Fourier transform infrared spectroscopy. The biosorption data were analyzed using four non-linear kinetic (pseudo-first order, pseudo-second order and Elovich) and diffusion models (Weber-Morris). The time course data of biosorption processes fitted well to the pseudo-first and the pseudo-second-order kinetic models indicating ion-exchange and chemisorption as dominant mechanisms for metal ions removal from the alkalized juice. HNO3 as a desorption reagent showed the highest average molassigenic metal ions desorption efficiency (54.4%). Utilization of sugar beet biomass as cation-exchange material imposes as a potential solution for more successful sugar juice purification.

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