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Cellulose is a biopolymer with a wide range of properties like biocompatibility, hydrophilicity, porosity, good mechanical properties, biodegradability and non-toxicity. The properties and application of cellulose based materials are related to the source of the cellulose production. Despite the fact that the plant cellulose is playing a leading role in obtaining cellulose fibers, it has been found that ecologically and economically, a better source for obtaining cellulose is by fermenting a particular strain of bacteria. Although bacterial nano cellulose (BCN) based materials can be used in numerous industries, from the paper and food industries to biomedicine, their application in electronics is limited because bacterial cellulose does not have conductive and ferromagnetic properties. Having this in mind in this research, the results of the development of nanocomposite materials based on BCN modified with Fe3O4 has been presented. The differences in the interaction of Fe3O4 nanoparticles and BCN obtained by varying precipitation parameters were investigated and the effect of reaction time was followed by SEM-EDS, XRD, and FTIR analysis. It has been found that this type of modifications of the initial BCN, enables development of new composite materials with superior properties, which can be used in various fields of electronics. IX Serbian Ceramic Society Conference - Advanced Ceramics and Application : new frontiers in multifunctional material science and processing : program and the book of abstracts; September 20-21, 2021; Belgrade

Medicinal and aromatic plants promote good health and well-being. Workshop titled: „Spices and therapeutic herbs in diet“

Sustainable development, inaugurated by a series of national strategy documents and emphasized by European Union, requires the application of principles of the concept of sustainable development. It includes process management, public communication and the development of a new system of values in which environmental concerns occupy a significant place. In the food industry, rapid implementation of improvements in “ecoefficiency” or energy efficiency is required, whereas it is necessary to identify a wide range of (useful) natural materials by minimizing waste generation (zero waste). In addition to the circular economy, the techniques, tools and methods used in sustainability assessments are needed. Besides knowledge of processes and technologies in food technology and biotechnology, sustainable tools are future necessity to be applied in order to provide strategic development of companies, product development and product system improvements, with good marketing positioning. It is important to consider and to apply advanced thermal and nonthermal (“green”, sustainable) processing techniques in biosciences, and to critically consider the advantages and disadvantages of certain techniques, which is in line with the Global Sustainable Development Goals (2030). Advantages of using advanced thermal and nonthermal techniques in sustainable development are visible through small gas emissions ; through fast and efficient processes, low energy consumption, lower working temperatures, and efficient microbiological safety. Special emphasis is placed on the use of sustainable techniques in food technology, fermentation, biotechnological processes, by-products processing, etc., by implementing sustainable techniques in existing food processing lines. Along with the standard methodology of analysis, there are tools and concepts such as: Quality Function Deployment, Green Technology, Clean Label, Clean Processing and Production, Carbon Emission, Waste and Water Footprint, Zero Waste and Life Cycle Assessment (LCA). LCA is a vital and powerful tool that encompasses the assessment of overall environmental impact, while complementing other, equally-needed methods and processes to effectively and efficiently maintain consumption and production. This is in line with the long-term international interest in the so-called “clean technology” and the sustainable development required to improve “eco-efficiency” through the life cycle of a particular product or system, which is particularly important in the food industry.

Dandelion ( Taraxacum officinale) leaves and roots are good sources of health-promoting phytochemicals. Generally, applications of modern green extraction techniques, such as High Hydrostatic Pressure Assisted Extraction (HPAE) and Pressurized Liquid Extraction (PLE) showed significant advantages over conventional extractions in terms of less solvent and energy consumption, shorter extraction time, higher yields, etc. Thus, it could be useful for the effective extraction of various bioactive compounds from plant materials. In line with this, the aim of this study was to investigate the use of HPAE and PLE for the recovery of polyphenols from dandelion leaves and roots. Studied parameters for HPAE were: ethanol concentrations (50 and 70%), high pressures (300, and 500 MPa), times (5 and 15 min), and temperatures (22 and 60°C) PLE was conducted at constant static time (5 min) and pressure (10.34 MPa) by varying: ethanol concentrations (50 and 70%), temperatures (60, 80 and 100 °C), and number of extraction cycles (1, 2 and 3). Optimal HPAE parameters for the polyphenols recovery of dandelion leaves and roots was at 5 min, 60°C, and 500 MPa, with 70% ethanol (v/v) that was the most effective solvent for the leaves ; and 50% ethanol (v/v) for the dandelion root extract. Dandelion leaves extract was richer with polyphenols than the root extract (44.99 vs.11.46 mg GAE/g). With respect to PLE, 50% ethanol (v/v) was the most appropriate extraction solvent from both plant matrices. Moreover, optimal PLE conditions with the highest recovery (93.94 mg GAE/g) for the leaves were 60°C with 2 extraction cycles, while for the roots highest yields (5199 mg GAE/g) were achieved under higher temperature and longer extraction time (80°C and 3 extraction cycles). In conclusion, both extraction techniques were suitable for the efficient green recovery of polyphenols from dandelion leaves and roots. However, according to obtained results PLE performance has proven to be more suitable than the HPAE. Therefore, it should be recommended for the fast and effective polyphenols recovery from both, leaves and roots.

1) microwave extraction of Dalmatian sage (Salvia officinalis L.) extracts that aimed to evaluate the influence of solvents (30% ethanol/water, v/v ; 30% acetone/water, v/v ; water), time (3, 5, 7, 9, 10 min), temperature (30, 50, 60, 80 °C), and acidity (addition of 10 % HCl) on polyphenolic recovery. Total polyphenols were best extracted with 30% acetone/without HCl/T=80°C for 10 minutes. The main polyphenol, rosmarinic acid was best extracted with 30% ethanol/with HCl at T=80°C for 10 minutes ; 2) cold atmospheric gas phase plasma extraction of anthocyanins from pomegranate (Punica granatum L.) juice. Plasma treatment covered different operating settings: (i) time (3, 5, 7 min), (ii) juice volume (3, 4, 5 cm3), and (iii) plasma gas flow (0.75, 1, 1.25 dm3/min). Anthocyanins were best stable at: 3 min of treatment time, 5 cm3 sample volume, and 0.75dm3/min gas flow. Anthocyanin content was higher for 21-35% in plasma treated samples vs. fresh juices. In summary, it was shown that plasma treatment had positive influences on anthocyanins stability in cloudy pomegranate juice ; 3) cold atmospheric gas phase plasma of chokeberry juice (Aronia melancarpa) extracts that aimed to evaluate influence of different treatment times and juice volumes under constant gas flow (0.75 dm3min-1) on polyphenolic content. All samples were compared to the fresh and pasteurized chokeberry juice (80°C/2min). Plasma treatment better preserved hydroxycinnamic acids, but showed loss of anthocyanins. Pasteurisation negatively affected hydroxycinnamic acids, while flavonols and anthocyanins were well preserved.

The aims of this study were to evaluate the potential of accelerated solvent extraction (ASE) for the recovery of polyphenols from olive leaves extracts. Extracts were obtained from indigenous Croatian olive variety (Olea europaea, cv. Oblica) in order to assess its suitability for the use as raw material in functional food production. Outcome variables were the contents of: (i) total polyphenols (TP) ; (ii) total flavonoids (TF) ; hydroxycinnamic acids (HCA) ; and (iv) flavonols (FLA). Extraction parameters were: cycle number (1, 2) ; temperature (60, 80, and 100°C) ; and static extraction time (5, 10, and 15 minutes). Maximum content of the: TP=53.15 mg GAE/g ; TF=16.51 mg QE/g ; HCA=1.66 mg CA/g ; and FLA=8.66 mg QE/g. TP were best extracted with two 5-minute cycles at T=80.38°C ; flavonoids with one 15-minute cycle at T=100°C ; HCA by two 15-minute cycles with T=91.29°C ; and flavanols by one 5-minute cycle at T=87.41°C. Results showed that ASE is a good choice for extracting polyphenols from the olive leaves for industrial processing.

Asymmetric flow of information is the key feature of the ADSL (Asymmetric Digital Subscriber Loop) technology, i. e. higher data transmission rate towards the user than from the user towards the network. Characteristic is the short message sending by the user with a certain request to the server. The server responds to the request by a significantly longer message of various electronic forms (data, digitized speech, pictures or video). Therefore, this technology is most often used by small and medium users. ADSL is currently the only commercially available DSL technology which is still experiencing the breakthrough on the service market. It enables faster access to the Internet, LAN (Local Area Network), videoconferencing, VoD (Video on Demand) and interactive multimedia. In order to standardize such services, the ITU (International Telecommunications Union) G. 992.1 (standardized DMT-discrete multi-tone line coding technology) and ANSI (American National Standards Institution) T1.413-95/98 are used for ADSL. DMT (Discrete Multi Tone), as the more popular one, uses the line coding technique, which splits a certain frequency range into several sub-channels. Most of these sub-channels are used for upstream and downstream transmission of speech and data, whereas some are used as pilot signals or kept in reserve. Such modulation technique expands the frequency spectrum, allowing the usage of broadband services per one pair of wires. In this way the sharing of speech and data service transmission is realized.

Elementi u tragovima vodotoka špilje Veternica (Medvednica), kakvoća podzemne vode.

The effect of replacing the wheat with the maize, soy and rice flour and breadcrumbs in the formulation of the gluten-free coating mixture for fried food products was investigated. Six different coating butters were prepared by mixing water and egg white with wheat (control), maize, soy and rice flour, as well as with the mixture of maize and soy flour (50:50) and maize and rice flour (50:50), respectively. Dry breadcrumbs from the previously baked wheat, maize, soy and rice bread were also prepared. Turkey nuggets, made from minced turkey breasts, were dipped in the prepared wet coating batters and breadcrumbs and deep-fried in the palm oil for 3 minutes. Sensory evaluation, colour determination, oil uptake and texture profile analysis (hardness, springiness cohesiveness, chewiness and resilience) of turkey nuggets were performed. In addition to that, textural properties of fried coating that was removed from nuggets were also determined. Results showed that only the addition of soy flour decreased the acceptability of nuggets. Replacing the wheat flour and breadcrumbs with that of maize and rice did not deteriorate the fried nuggets characteristics and some of the properties (colour, appearance and total sensory score) were even better when maize and maize/rice mixture were used. In conclusion, in order to benefit consumers with celiac disease and gluten intolerance, maize and rice flour could be used as an excellent replacement for wheat which is traditionally used in the formulation of the coating mixture for fried food products.