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Copyright of Kemija u Industriji is the property of Croatian Society of Chemical Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Agriculture / Poljoprivreda is the property of Josip Juraj Strossmayer University of Osijek, Faculty of Agriculture in Osijek and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Agriculture / Poljoprivreda is the property of Josip Juraj Strossmayer University of Osijek, Faculty of Agriculture in Osijek and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The PA 2200 waste powder generated during selective laser sintering (SLS) process is an important environmental and economic problem. In order to test and modify the properties of the waste powder, nanocomposites based on polyamide matrix and TiO2 nanoparticles were prepared in this work. Agglomerates of the TiO2 nanofiller are visible on the SEM micrographs for the nanocomposite with 5 wt. % of the nanofiller (Fig. 1). The DSC analysis indicates an increase in crystallization temperature (Tc) by the addition of filler to the polymer matrix and it can be concluded that the TiO2 nanoparticles represent the nucleation centres in the PA matrix (Fig. 2, Table 1). In systems with 4 and 5 wt. % TiO2 crystallization enthalpy (ΔHc) and melting enthalpy (ΔHm) are higher than the values for the polyamide matrix (Table 1), indicating that the nanoparticles promote crystallization of the PA matrix. The results of TG analysis imply a positive effect of the TiO2 nanoparticles on the onset of thermal decomposition, which is most pronounced in the system with 3 wt. % TiO2 (Fig. 3, Table 2). As thermal degradation progresses further, the positive effect of the addition of TiO2 nanoparticles becomes less pronounced and finally becomes negative in the final stages, i.e. TiO2 nanoparticles accelerate the degradation. The thermal conductivity values (λ) are slightly higher for the nanocomposites relative to the pure PA matrix (Fig. 4) due to the formation of a more ordered structure of the polymer matrix by the addition of TiO2 and/or the formation of socalled conductive pathway. The results of the mechanical test indicate that the addition of TiO2 nanofiller decreases the values of the secant modulus (E), while the values of the yield stress (σy) and yield elongation (εy) change slightly relative to the values obtained for the pure polymer matrix (Table 3). In conclusion, the addition of TiO2 nanoparticles to the PA 2200 waste powder represents a useful approach for its reuse, thus improving the economic and environmental sustainability of the SLS process. The main disadvantage of the studied systems is the inconsistent mechanical properties at break. In future studies, this problem will be solved with adequate surface modification of TiO2 nanoparticles. [ABSTRACT FROM AUTHOR]

The PA 2200 waste powder generated during selective laser sintering (SLS) process is an important environmental and economic problem. In order to test and modify the properties of the waste powder, nanocomposites based on polyamide matrix and TiO2 nanoparticles were prepared in this work. Agglomerates of the TiO2 nanofiller are visible on the SEM micrographs for the nanocomposite with 5 wt. % of the nanofiller (Fig. 1). The DSC analysis indicates an increase in crystallization temperature (Tc) by the addition of filler to the polymer matrix and it can be concluded that the TiO2 nanoparticles represent the nucleation centres in the PA matrix (Fig. 2, Table 1). In systems with 4 and 5 wt. % TiO2 crystallization enthalpy (ΔHc) and melting enthalpy (ΔHm) are higher than the values for the polyamide matrix (Table 1), indicating that the nanoparticles promote crystallization of the PA matrix. The results of TG analysis imply a positive effect of the TiO2 nanoparticles on the onset of thermal decomposition, which is most pronounced in the system with 3 wt. % TiO2 (Fig. 3, Table 2). As thermal degradation progresses further, the positive effect of the addition of TiO2 nanoparticles becomes less pronounced and finally becomes negative in the final stages, i.e. TiO2 nanoparticles accelerate the degradation. The thermal conductivity values (λ) are slightly higher for the nanocomposites relative to the pure PA matrix (Fig. 4) due to the formation of a more ordered structure of the polymer matrix by the addition of TiO2 and/or the formation of so called conductive pathway. [ABSTRACT FROM AUTHOR]

This study is focused on the application of high-voltage electric discharge (HVED) to recover some bioactive compounds from the cocoa bean shell. Different extraction times (30, 60, 90 min), frequencies (40, 70, 100 Hz) and solvent-solid ratios (10, 30 and 50 mL g-1) were used to obtain cocoa bean shell extracts. Desired bioactive compounds, methylxanthines and phenolic compounds were measured in obtained extracts by high-pressure liquid chromatography with diode array detector. The obtained extracts showed that theobromine was the most abundant, ranging from 2530.13 to 6031.51 mg kg-1, while caffeine content was in the range from 316.08 to 849.88 mg kg-1. In addition, significant amounts of phenolic compounds were found, namely catechin (115.91 to 284.33 mg kg-1), epicatechin (20.20 to 358.90 mg kg-1), and gallic acid (80.28 to 219.17 mg kg-1). Results showed that different parameters of HVED extraction have statistically significant influence on cocoa bean shell composition, suggesting how this byproduct can be used in the production of valuable extracts. [ABSTRACT FROM AUTHOR]

Copyright of Glasnik Zastite Bilja is the property of Zadruzna Stampa D.D. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Glasnik Zastite Bilja is the property of Zadruzna Stampa D.D. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Agriculture / Poljoprivreda is the property of Josip Juraj Strossmayer University of Osijek, Faculty of Agriculture in Osijek and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Agriculture / Poljoprivreda is the property of Josip Juraj Strossmayer University of Osijek, Faculty of Agriculture in Osijek and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Glasnik Zastite Bilja is the property of Zadruzna Stampa D.D. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Glasnik Zastite Bilja is the property of Zadruzna Stampa D.D. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Oxidation of vegetable oils has been recognized as a major problem in edible oils; it causes a change in the chemical, sensory and nutritional properties. In this study the effect of addition of natural antioxidants (in concentration of 0,2%) on the oxidative stability of extra virgin olive oil, high-oleic sunflower oil and their mixtures (80:20, 50:50) were investigated. The two types of 100% natural rosemary extracts (OxyLess CS and StabilEnhance OSR) and green tea extract were used as natural antioxidants. Oxidative stability of vegetable oils, their mixture and oil with and without added antioxidants was investigated using the Schaal Oven test. The test results are shown in peroxide value over 4 days of the test. High-oleic sunflower oil has better stability to oxidation due to the high proportion of oleic acid. The research results show the higher antioxidant activity of a rosemary extract Oxy'Less CS in relation to StabilEnhance OSR and green tea extract. The addition of rosemary extract StabilEnhance OSR (0,2%) leads to a very little increase in the stability of oils and their mixtures in relation to the oil without added antioxidants. Application of used antioxidants increases the oxidative stability of the tested vegetable oils and their mixtures. [ABSTRACT FROM AUTHOR]

Extrusion is a significant process in the food industry, where corn grits is often used as the main raw material to which various types of flours can be added to increase nutrition value and to improve physicochemical properties. Chickpea (Cicer arietinum L.) is one of the world's most important grain legumes bacause it is a valuable source of protein, minerals and vitamins, and plays a very important role in human diets in many areas of the world. The aim of this study was to determine the effect of chickpea flour addition (5%, 10% and 15%) on properties of corn grits extrudates. Samples with 15% of moisture content were extruded in the laboratory single screw extruder at temperature profile 135/170/170 °C, using a screw with compression ratio 4:1 and die with 4 mm diameter. Obtained extrudates were air-dried, and physical and rheological properties were determined. The obtained results showed that the addition of chickpea flour to corn grits resulted in increase of expansion ratio (ER) and fracturability, whereas bulk density (BD) and hardness of extrudates decreased. Addition of chickpea flour and extrusion process resulted in significant colour change, where the total colour change (ΔE) increased proportionaly to the chickpea level, with more pronounced change in extruded products. After extrusion process, peak, hot and cold viscosity decreased in all samples, and the extruded samples were less prone to retrogradation. [ABSTRACT FROM AUTHOR]

The aim of this research was to investigate the influence of the addition of tomato powder (TP) to corn grits at levels 4, 6 or 8% and the addition of ascorbic acid (AA) at levels 0.5 and 1%, on total polyphenol content (PF), and antioxidant activity of the extrudates. The hardness and the expansion ratio of the extruded products were also tested. Mathematical models that describe the influence of additives on the mentioned properties were also determined. Extrusion was performed at two temperature regimes: 135/170/170 °C and 100/150/150 °C. Lower temperature regime led to increased hardness and the expansion of extrudates. The addition of tomato and AA led to decreased hardness and the expansion at both temperature regimes. The addition of tomato increased PF and AA compared with pure corn extrudates. Greater degradation of PF and AA was at lower temperature regime. High correlation between PF and AA was demonstrated at both extrusion temperatures. [ABSTRACT FROM AUTHOR]

The aim of this research was to examine the potentiality of enrichment of extruded corn products by addition of rye, which is arich source of dietary fibres and bioactive components. Corn grits with ≤500 µm and grits with particle size >500 µm were used. Rye flour was added in 20% (d. m.). Extrudates were produced in the laboratory single screw extruder at 135/170/170 °C. Rye addition caused a decrease of expansion ratio, lightness and fracturability and an increase of bulk density, colour saturation and hardness of extrudates. When grits of larger particle size were used, lightness of samples increased after extrusion, while it decreased for smaller particle size. Starch damage largely increased after extrusion, as well as the absorption index and solubility, while viscosity decreased. Rye addition decreased starch damage. [ABSTRACT FROM AUTHOR]

Copyright of MESO is the property of Zadruzna Stampa D.D. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the past few decades, the Cannabis sativa L. hemp variety has been unfairly neglected because of its similarity to the illegal kind Cannabis indica used as a narcotic. The objective of this study was to evaluate the process of oil extraction from Cannabis sativa seeds by cold pressing, followed by extraction with supercritical CO2. In the pressing experiments, the response surface methodology was conducted in order to study the effects of temperature, frequency, and nozzle size on oil recovery and quality parameters. The optimal condition for obtaining the highest oil recovery (23.34%) and the best oil quality within the experimental range of the variables studied was at temperature of 60 °C, frequency of 20 Hz, and nozzle of ID 6 mm. The residual oil (10.33%) in the press cake was extracted totally by supercritical CO2 in a newly designed supercritical fluid extraction system. Oregano essential oil was the most effective in protecting the oil from oxidative deterioration. [ABSTRACT FROM AUTHOR]

Edible films and coatings are active packaging systems used in food production that are gaining increasing attention. In addition to food protection and shelf-life extension, the advantage of edible films is their safety for consumption, unlike other packaging materials that pose environmental issues. Basic film forming components are proteins, lipids and/or polysaccharides. Plasticizers, antimicrobials, antioxidants, colours and/or aroma are often added. Recent research studies are mainly focused on the application of natural antimicrobials in edible films for meat and minimally processed vegetable application. The aim of this review is to give an overview of most important knowledge in edible film and coating applications in the food industry. [ABSTRACT FROM AUTHOR]

Production trend in the chocolate industry is to purchase finished cocoa liquor or finished chocolate mass which is then used in production of different chocolate products. If the finished chocolate mass is supplied to the facility, it is used within 30 days. The rheological properties of chocolate are highly important in quality determination and consumer preference. Since chocolate is a non-Newtonian fluid, its properties could be changed during the afore mentioned storage period. The aim of this research was to monitor the rheological properties of dark chocolate during 30-day storage at 50°C. Different emulsifiers (lecithin, PGPR, citric acid esters of and mono- and diglycerides of fatty acids (citrem) and citric acid esters of and mono- and diglycerides of fatty acids 2in1 (citrem 2in1)) were added to the chocolate in order to elucidate the influence of an emulsifier on the rheological properties during storage. The results showed that the rheological properties of all chocolate samples changed during storage. The addition of lecithin lowered plastic viscosity and yield value. At the end of the storage period, the yield value of the chocolate mass with lecithin increased, while other emulsifiers decreased its value. [ABSTRACT FROM AUTHOR]

Apple distillates are a common drink in Western European regions and considered as a high quality product. There are many factors that will influence the production and the quality of apple distillates. The aim of this work was to produce apple distillates by column devices with different rectification index (1, 1.75 and 2.6) and by alambic device (classic process and double distillation). Distillates were analyzed to determine chemical composition, aroma profile and sensory properties. Apple distillates produced by column process had significant higher ethanol content, but lower aldehydes, higher alcohols, esters and monoterpenes. All samples had very low concentration of methanol and furfural. Apple distillates produced by column process had significant higher grades of sensory properties. [ABSTRACT FROM AUTHOR]

Copyright of MESO is the property of Zadruzna Stampa D.D. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Application of native starch in food production is highly limited due to retrogradation, instability in acid conditions and at high temperatures etc. To overcome these problems and extend starch application, native starch is modified by chemical, physical and enzymatic procedures. The aim of this research was to prepare different modified starches from commercial native potato starch by acetylating (with acetanhydride), cross-linking (with sodium tripolyphosphate, STPP) and combination of these procedures, and to determine their rheological and thermophysical properties. The results showed that all modified starches had lower gelatinisation temperature and lower gelatinisation and retrogradation enthalpy than native starch. Dual modification with higher proportion of cross-linking reagent resulted in 50%-decrease of gelatinisation enthalpy compared to native starch. Acetylated and acetylated cross-linked starch had lower peak viscosity, whereas cross-linked starch had higher peak viscosity than native counterpart. While acetylating resulted in increase of % breakdown, other applied modifications resulted in its decrease. Swelling power and solubility increased by acetylating and decreased proportionally to increase of cross-linking reagent both by cross-linking and dual modification. [ABSTRACT FROM AUTHOR]

Quality of plum brandy is influenced by many factors, such as: climate characteristics, soil characteristics, characteristics of plum (Prunus domestica) varieties and technological characteristics of manufacturing process. The aim of this work was determination of the quality of Croatian "home-made" plum brandies produced by authentic production process from the Croatian region of Slavonia. For detection of volatile flavor components and quality of plum brandy, gas-chromatography and sensory analysis were applied. Home-made Croatian plum brandies as distillates of Prunus domestica contain numerous ingredients. Some of these ingredients are desirable and important for the quality of distillates, and some are undesirable. The obtained results show that all samples had a higher content of aldehydes and higher alcohols, ethanol content was in range 43.02 -- 44.5 % vol. [ABSTRACT FROM AUTHOR]

Copyright of MESO is the property of Zadruzna Stampa D.D. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of MESO is the property of Zadruzna Stampa D.D. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of MESO is the property of Zadruzna Stampa D.D. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of MESO is the property of Zadruzna Stampa D.D. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Extrusion process is one of the most important innovations of the 20th century applied in many industries. Extrusion is a technology that is increasingly used for the production of various food products, especially snacks and breakfast cereals. Supercritical carbon dioxide (CO2) as a non-toxic, non-flammable and inexpensive, is applied in many processes, including the extrusion technology. Supercritical CO2 extrusion process (SCFX) found its application primarily in the processing and manufacturing plastic, but recently more and more begins to be applied in food production and processing. Scientific researches in this area are based in production of extrudates with improved properties compared to conventional extrusion process without the addition of CO2. A number of applications of SCFX in food processing technology will be reviewed and numerous advantages over the conventional process will be described in this paper.

In the hazelnut oil production it is very important to find an appropriate method to recover the oil from kernels. The objective of this study was to evaluate the oil extraction process from hazelnuts by screw pressing followed by extraction with supercritical CO2. The effects of temperature head presses, frequency and nozzle size in pressing experiments on oil temperature and recovery were monitored. The optimal pressing condition using response surface methodology was determined. In obtained hazelnut oil the following quality parameters were determined: peroxide value 0 mmol O2/kg, free fatty acids 0.23%, insoluble impurities 0.42%, moisture content 0.045%, iodine value 91.55 g I2/100 g, saponification value 191.46 mg KOH/g and p-anisidine value 0.19. Rosemary extract was the most effective in protecting the oil from oxidative deterioration. The residual oil that remained in the cake after pressing was extracted totally with supercritical CO2 and such defatted cake, free of toxic solvents, can be used further in other processes.

The subject of the work is the possibility of applying microfiltration through a ceramic tubular membrane with 100 nm pore sizes to the steepwater obtained in the production process of corn starch. The dry matter content should be reduced in the steepwater permeate. Thus the consumption of the process water would be reduced, the nutrients from the steepwater could be exploited as feed and the wastewater problem would consequently be solved. The objective of the work was to examine the influence of the operating parameters on the permeate flux during steepwater microfiltration. The parameters that vary in the course of microfiltration, were the transmembrane pressur and flow rate, while the permeate flux and dry matter content of the permeate and retentate were the dependent parameters, constantly monitored during the process. Another objective of this study was to investigate the influence of static turbulence promoter on the permeate flux during steepwater microfiltration. Static mixers enhance permeate flux, thus the microfiltration can be performed longer. As a result of the statistical analysis, the optimal conditions for steepwater microfiltration were determined. The maximum value of the permeate flux without mixer (25 lm-2h-1) was achieved at a pressure of 2 bars and a flow rate around 100 lh-1. With the use of static mixer the flux is 2,5 times higher compared to the one obtained without the mixer. The dry matter content of the permeat after 2.5 hours of mucrofiltration was lowered by 40%.