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The nutritional quality and sensory properties of virgin olive oils (VOO) are strongly influenced by a complex endogenous enzyme system. The activity of these enzymes can be influenced by the process conditions during oil production. The aim of the present study was to determine the influence of flash thermal treatment (FTT) on lipoxygenase activity and on the formation of volatile compounds. Olive fruits from Istarska bjelica and Levantinka were used for this experiment. FTT was performed as a pretreatment to malaxation by rapid cooling or heating from 15 to 40 °C. Lipoxygenase was isolated from the olive paste after malaxation, and its activity was determined by measuring the concentration of hydroperoxides formed by the HPLC method. The volatile compounds of VOOs were analyzed by SPME - GC/MS. The results show that lipoxygenase activity is cultivar dependent, with Levantinka having significantly higher activity. Consequently, Levantinka VOOs have significantly higher concentrations of lipoxygenase pathway volatile compounds. FTT had no significant effect on lipoxygenase activity, although the trend of decreasing activity with increasing temperature was observed. However, volatile compounds of the produced oils were temperature dependent, and their concentration increases from 15 °C to 20 °C for Levantinka and to 25 °C for Istarska bjelica. Thereafter, it gradually decreases with increasing temperature. The concentration of secondary oxidation products was also determined to determine the influence of the temperature on the oxidation processes. Neither the cultivar nor the FTT had any effect on the oxidation products.

Innovative technologies are being widely studied for their application in the production of virgin olive oil. Flash thermal treatment is one of these techniques, since the regulation of temperature allows control over complex enzyme systems that affect the nutritional value, oxidative stability and sensory profile of virgin olive oil [1-3]. The aim of this study was to determine the effects of flash thermal treatment (both cooling and heating) on the antioxidant activity of virgin olive oil from four different varieties (Oblica, Rosulja, Istarska bijelica and Levantinka). Flash thermal treatment was applied at 6 different temperatures in the range of 15-40 °C. It was used as a malaxation pretreatment for the production of virgin olive oil on a laboratory scale using the Abencor system. The antioxidant activity of the produced oils was determined using the DPPH method previously described by Kraljić et al [4]. The results show a significant influence of the variety and pretreatment on the antioxidant activity of virgin olive oil, as well as their interaction. Rosulja had the highest antioxidant activity (90.8% on average) compared to the other three varieties (84.3, 75.6 and 74.8% for Oblica, Istarska bijelica and Levantinka, respectively). In relation to the applied flash thermal treatment, Oblica, Rosulja and Levantinka showed significantly higher antioxidant activity at the highest temperature (40 °C), while Istarska bijelica responded better to mild temperatures (20-30 °C).

High concentrations of polyphenols, in combination with other components present in olive mill wastewater, make a big environmental problem when released into nature due to high phytotoxicity and antimicrobial properties as well as genotoxicity, which limits the biodegradation of wastewater. The aim of the work was a degradation of model solutions by high voltage electrical plasma discharge (HVED). The model solution was composed of polyphenols commonly present in the highest concentrations in olive mill wastewater hydroxytyrosol, tyrosol, vanillic acid and oleuropein. Plasma treatment was operated at a frequency of 60 Hz, a voltage of 40 kV and through time 10, 20 and 30 minutes. The initial samples were adjusted to a pH value of 7 and 10. During the treatment nitrogen (N2) gas was bubbled into the liquid to improve treatment properties. Sample temperature, electrical conductivity, pH value and polyphenol reduction were monitored during the treatment and samples were also analysed by NIR spectroscopy. In all samples, polyphenol degradation is noticeable already after 10 minutes of treatment with a reduction of over 50% for hydroxytyrosol, tyrosol and vanillic acid and a reduction of over 99% for oleuropein.

Nowadays, consumers are increasingly looking for high-quality foods and food products that have positive impacts on health. Therefore, the demand for functional foods has also increased. Strawberry can be considered as a functional food due to its nutritional and biological composition. However, due to its short shelf life, it is usually consumed fresh, nevertheless, there is also growing interest for their juices. Juices are usually preserved by thermal technologies although the application of high-temperature treatments negatively affects the nutritional quality of the food. For this reason, the development and application of non-thermal processing technologies, such as a pulsed electric field (PEF), has attracted much attention. The aim of this study was to investigate the effects of PEF technology on soluble solids content (SSC), pH, and stability of polyphenols in strawberry juice during seven days of storage at 4 °C. Juice was prepared from strawberries (Fragaria x ananassa Duch.) cultivar 'Albion', whose fruits were harvested at 75 % (J1) and 100 % (J2) maturity. The parameters of the PEF treatment were: (i) electric field strength (40 and 50 kV), (ii) frequency (100 and 200 Hz), and (iii) treatment duration (3 and 6 min). All results were analyzed by multifactorial analysis of variance (p≤0.05). Total polyphenolic content (TPC) was determined by the Folin Ciocalteu spectrophotometric method. The control (untreated) samples of strawberry juice J2 had significantly higher SSC, significantly higher pH, and significantly lower TPC compared to the control samples of strawberry juice samples J1. Storage of the control samples of strawberry juice at a temperature of 4°C for seven days resulted in a significant decrease in SSC and pH, and a significant increase in TPC. Treated samples of strawberry juice J1 had significantly lower SSC and pH than treated samples of strawberry juice J2. Treated juice samples of both ripeness levels stored at 4°C for seven days had significantly lower SSC, while pH values were not significantly different from the first day of storage. The electric field strength of 50 kV proved to be the only statistically significant parameter of the PEF technology that led to a significant increase in TPC, as compared to the 40 kV strength. PEF- treated J1 samples had significantly higher TPC than J2. Regardless of maturity, storage of treated samples at a temperature of 4°C for seven days resulted in a statistically significant increase in TPC. In general, it can be concluded that PEF technology positively affects the stability of TPC in strawberry juices during seven days of storage at 4°C, and that strawberries with lower ripeness are also suitable for the production of functional fruit juices.

The effects of PEF technology on the content of anthocyanins (ANT), hydroxycinnamic acids (HCA) and flavonols (FL) in strawberry juices from the strawberry (Fragaria x ananassa Duch.) cultivar 'Albion' harvested at 75 % maturity (J1) and 100 % maturity (J2) and stored at +4 °C for 7 days were evaluated. The parameters of the PEF treatment were: (i) electric field strength (40 and 50 kV/cm), (ii) frequency (100 and 200 Hz), and (iii) treatment duration (3 and 6 min). All results were analyzed by multifactorial analysis of variance (p≤0.05). The untreated juice J2 had higher ANT, HCA and FL values than the untreated juice J1. After 7 days of storage at 4 °C, the control samples showed decreasing values of FL and increasing values of ANT and HCA. The treated juice samples of both maturity levels stored at 4 °C for seven days had significantly lower FL, while the values of ANT and HCA were significantly higher on the first day of storage. The electrical strength of 50 kV showed a statistically significant effect on the increase of ANT, HCA and FL content compared to the 40 kV strength. In contrast to the electrical strength, increasing the frequency from 100 Hz to 200 Hz resulted in a statistically significant decrease in ANT, HCA, and FL. Treatment duration did not show a statistically significant effect on ANT and HCA, with the exception of FL, where an increase in treatment duration resulted in a decrease in the levels of FL. PEF-treated J2 samples had significantly higher ANT, HCA and FL than J1. Regardless of maturity, storing treated samples at a temperature of 4 °C for seven days resulted in a statistically significant increase in ANT, HCA, and a decrease in FL. In general, it can be concluded that PEF technology positively affects the stability of ANT and HCA in strawberry juices during seven days of storage at 4 °C. Among the PEF process parameters, electric field strength and frequency had a statistically significant effect on the content of ANT, HCA and FL in the juices.

The oxidative stability of fats and oils is a crucial parameter that determines the shelf life of a product, but also the general use of the fats and oils. Differential scanning calorimetry (DSC) is a promising new technique that is fast, reliable and uses the exothermic character of the oxidation reaction to determine the induction time (in the isothermal DSC method) or the induction temperature (in the non-isothermal, i.e., dynamic DSC method). The objective of the present study was to optimize the conditions of the DSC method to determine the oxidative stability of virgin olive oil. Both the isothermal and dynamic methods were developed on a 214 Polyma DSC (NETZSCH-Gerätebau GmbH) and optimized using extra virgin olive oil from the Croatian market. The parameters studied were sample size (4, 8 and 12 mg), sample preparation (use of an open or a sealed pan with a pinhole), temperature (130, 140 and 150 °C) for the isothermal method and heating rate (5, 10, 15 and 20 °C/min) for the dynamic method. The results show that the DSC method is a reliable method for determining oxidation stability for both isothermal and non-isothermal methods. Sample size did not affect induction time, but a smaller portion size resulted in better reproducibility of the results. Regarding sample preparation, there was no statistical difference between results obtained with an open or sealed aluminum pan. However, it is better to use a hermetically sealed pan with a pinhole to protect the instrument from possible contamination. The induction time at 130 °C was 287 minutes, which was considered unacceptable, while a temperature of 140 °C proved to be optimal. A temperature of 150 °C also showed satisfactory reproducibility of results, but a longer induction time at 140 °C makes it easier to track changes between different oils or during storage. For the determination of the induction temperature (dynamic DSC), a heating rate of 15 °C/min proved to be optimal. Although repeatable results were also obtained with a heating rate of 10 °C/min, the use of a higher temperature rate can significantly speed up the analysis. The other two heating rates were considered unsuitable due to the lack of reproducibility.

Degradation of Polyphenols in agro-industrial wastewaters is lately a very important topic because of its complex biodegradation and high phytotoxic and antimicrobial properties that make them dangerous to the environment [1, 2]. The main aim of this study was to investigate the effect of high voltage plasma treatment on polyphenols commonly present in olive mill wastewater. A model solution made of hydroxytyrosol, tyrosol, oleuropein and vanillic acid was prepared at pH values of 7 and 10. Plasma treatment parameters were set at a fixed frequency of 60 Hz, high voltage of 40 kV and 50 kV in combination with air bubbled into the liquid and treatment times 10, 20 and 30 minutes. Physico-chemical parameters (pH value, electrical conductivity, NO2-, NO3- and H2O2) and concentration of polyphenols were determined in all samples. Degradation of polyphenols occurred in all samples, but the most efficient treatment (>90%) occurred at 50kV treatment after 20 minutes at pH 10. The obtained results show potential for further research on the chemistry of degradation intermediates as well as a step forward to the application of high voltage gas plasma discharge on olive mill wastewater decomposition.

Aim: Pulsed electric field (PEF) is an emerging new technology that is finding more and more applications in the food sector. Virgin olive oil is no exception, as its application can significantly increase oil yield. However, changes in the chemical composition of virgin olive oil vary from study to study. This could be due to the fact that the chemical composition of the oil is directly influenced by the endogenous enzymes of the olive fruit responsible for the distribution of polyphenols in virgin olive oil and its sensory properties. Therefore, the aim of this study was to determine the effect of PEF on endogenous olive enzymes in model systems. Methods: Model systems of commercial enzymes (β-glucosidase and lipoxygenase) and their substrates (p- nitropheniygluco-pyranoside and linoleic fatty acid, respectively) were treated with HVG60/1 PEF (Impel, Zagreb, Croatia) for 1, 2, and 5 min with voltages of 0.1 and 0.5 kV/cm2 and a frequency of 25 and 125 Hz. Then, the treated enzyme/substrate solution was incubated at 25°C for 30 minutes to simulate a malaxation process. The activities of the enzymes were determined spectrophotometrically. Results: The activity of PEF-treated enzymes increased 4.5- fold for β-glucosidase and 2-fold for lipoxygenase compared to the untreated enzymes. The β- glucosidase activity measured immediately after PEF treatment was significantly affected by all factors and also by the interaction of voltage and time and frequency and time. Higher voltage resulted in an increase in β-glucosidase activity with longer treatment duration. After an additional 30-min incubation at 25 °C, β- glucosidase activity was affected only by PEF voltage, whereas it increased with higher voltage. Immediately after PEF treatment, lipoxygenase activity for linoleic fatty acid was significantly affected by treatment duration, with longer PEF treatments increasing activity. However, after incubation, longer treatment time resulted in lower amounts of hydroperoxides produced, which might be related to their spontaneous degradation. Conclusion: The introduction of PEF in virgin olive production as a pretreatment of malaxation could lead to a higher concentration of phenols and an improvement of the sensory characteristics of the oil due to an increased enzymatic activity.

Research background. The application of high power ultrasound combined with a slightly increased temperature on raw cow’s milk, skimmed cow’s milk and skimmed cow’s milk that passed the bactofugation process was analysed. We combined ultrasound with bactofugation of milk to achieve the microbiological accuracy that is equivalent to pasteurization. Experimental approach. The milk samples (200 mL) were treated for 2.5, 5, 7.5 and 10 min with high-power ultrasound (200 and 400 W) with a frequency of 24 kHz. The treatments were conducted with a constant duty cycle of 100%. Temperatures during the treatments were 20 and 55 °C. The somatic cell count of the aerobic mesophilic bacteria, as well the number of Enterobacteriaceae, Escherichia coli and Staphylococcus aureus cells were analysed. Results and conclusions. From the perspective of the reduction of the total count of bacteria, the best result was achieved by high-power ultrasound at 400 W treated for 10 min. High reduction of Enterobacteriaceae, E. coli and S. aureus cells was achieved with ultrasound treatment of raw, skimmed and skimmed cow’s milk that passed the bactofugation with a power of 200 and 400 W regardless of the treatment time. Novelty and scientific contribution. This work combines bactofugation and high-power ultrasound for the inactivation of microoganisms. This combination was used at a slightly increased temperature (up to 55 °C), which is much more economical than pasteurization, while it preserves the sensory and physicochemical properties of milk., Pozadina istraživanja. U radu je ispitan postupak obrade sirovog, obranog i baktofugiranog obranog kravljeg mlijeka ultrazvukom velike snage u kombinaciji s blago povišenom temperaturom. Ultrazvuk je kombiniran s postupkom baktofugiranja radi postizanja mikrobiološke ispravnosti mlijeka jednake onoj mlijeka obrađenog postupkom pasterizacije. Eksperimentalni pristup. Uzorci mlijeka (200 mL) tretirani su tijekom 2,5; 5; 7,5 i 10 min ultrazvukom velike snage (200 i 400 W), frekvencije 24 kHz. Tretmani su provedeni s konstantnim valnim ciklusom od 100 %. Temperature tijekom tretmana iznosile su 20 i 55 °C. Analiziran je broj somatskih stanica aerobnih mezofilnih bakterija, kao i broj bakterijskih stanica vrsta Enterobacteriaceae, Escherichia coli i Staphylococcus aureus. Rezultati i zaključci. Najveće smanjenje ukupnog broja somatskih stanica postignuto je obradom mlijeka ultrazvukom velike snage od 400 W pri trajanju od 10 min. Broj stanica bakterija Enterobacteriaceae, E. coli i S. aureus znatno je smanjen ultrazvučnom obradom sirovog, obranog i baktofugiranog obranog kravljeg mlijeka pri snazi od 200 i 400 W, neovisno o trajanju postupka. Novina i znanstveni doprinos. U radu su primijenjene dvije tehnologije, baktofugiranje i ultrazvuk velike snage, kako bi se u većoj mjeri inaktivirali mikroorganizmi u kravljem mlijeku. Kombinacija ova dva postupka obrade pri blago povišenoj temperaturi (55 °C) je puno ekonomičnija od procesa pasterizacije, a pritom su bolje očuvana senzorska i fizikalno-kemijska svojstva mlijeka.

Novel techniques such as 3D printing, enable the creation of snack foods with a tailored nutritional value and structure. The addition of bran for the enrichment of cereal foods with dietary fibre and bioactive compounds is frequently suggested. However, wheat bran contains a high level of polyphenol oxidase (PPO) which is associated with undesirable browning and reduction in antioxidant activity. This study aimed to investigate the influence of high-intensity ultrasound (HIU) (W=400 W, A=100%, t=2 min), vacuum microwave cooking (MW) (W=350 W, t=20 s) and pulsed light field (PL) (t=125 s, 3 pulses/s) processing of wheat bran, on its PPO activity, total phenolic content (TPC) and antioxidant activity (AO), the colour of 3D-printed dough, as well as on the precision and accuracy of 3D printing, and physical properties (colour, height, width, diameter) of baked snacks. TPC (Folin-Ciocalteu Method), AO (FRAP and DPPH), and PPO activity (AACC 22-85) were determined spectrophotometrically. The snack recipe consisted of oat flour, wheat bran (20% at flour basis), pea proteins, sunflower oil, salt, baking soda and water. Ten dough samples were 3D-extruded in the shape of a heart (20 layers) in duplicate using Createbot S3 printer. The 3D-printed shape accuracy and precision of baked samples were determined by digital image analysis, using ImageJ software, as a proportion of white pixels, and calculating the deviation of printed samples from the desired shape. Dough colour difference (ΔE*) between the first and the last printed sample (after 1 h) was determined by measuring lightness, redness, and yellowness using a spectrophotometer. Snacks were baked in a deck oven for 18 min with the lower heater at 140°C and the upper heater at 160°C. Height, line width and diameter of baked snacks, were determined using a calliper. Bran processing with HIU, MW and PL significantly reduced the PPO activity (by 75%, 73% and 65%, respectively), but also TPC and AO compared to unprocessed bran. Among all treatments, HIU processed bran showed highest values for TPC (0.74 ± 0.02 mg GAE/g d.w.) while PL resulted in lowest TPC values (0.59 ± 0.01 mg GAE/g d.w.) but the highest DPPH and FRAP values (1.17 ± 0.01 and 3.63 ± 0.08 μmol Trolox Eq/g d.w, respectively). Dough ΔE* after 1 h was very distinct (3.25). Compared to unprocessed bran, the addition of pre-processed bran resulted in significantly lighter and yellower 3D printed dough, which was darkening slower. In addition, bran pre-processing resulted in higher shape accuracy, while the top and bottom snack diameter were significantly larger when compared with unprocessed bran. Overall, dough with added HIU processed bran was printed with the highest precision (96%), while showing the lowest ΔE* (1.99), whereas PL resulted in the highest shape accuracy (96%) and the lightest snack. We can conclude that wheat bran pre-processing contributes to the physical properties of 3D-printed snack.

3D-printing is an emerging technology advantageous in the use of alternative raw materials such as grain by-products. This study aimed to investigate dough rheology, printing quality and textural properties of 3D-printed snacks and breakfast cereals made with grain by-products. Four snack recipes consisted of oat flour, sunflower oil, salt, baking soda, glucose oxidase, water, and either of the following: 1) wheat bran and pea protein (mixture WS), 2) pumpkin seed cake (WPFS), 3) defatted flaxseed flour (WFFS), 4) amaranth bran and rice protein (AS). Two breakfast cereal recipes consisted of oat flour, rice protein, wheat bran, baking soda, glucose oxidase, water, and sugar (WSBC) or honey (WHBC). Different 3D shapes were extruded using the Createbot S3 printer and baked at 180°C for 18 min (snack) or 10 min (breakfast cereal). 3D-printing precision, shape accuracy and deformation were determined by digital image analysis. Amplitude and frequency sweep tests were performed on dough using the MCR 92 Oscillatory rheometer (Anton Paar, Austria). Cutting tests were performed on final products with the TA.HDplus texture analyser (Stable Micro Systems, UK). All properties determined were significantly dependent on the dough mixture. The most viscous mixture with the largest G' and G'' values was WS. Dough for snacks printed with higher precision (between 95 and 98%) and shape was deformed less during baking (between -12 and -48%) than dough for breakfast cereals (between 68 and 82% and 75 and 80%, respectively). Snacks shrank, while breakfast cereals spread during baking. With the exception of AS mixture, baked snacks were harder (from 1.68 to 2.84 g) than the breakfast cereals (from 0.63 to 0.78 g). Overall, the WPFS dough mixture was printed with the highest precision (98%) and showed the highest shape accuracy (98%) and the lowest deformation (12%). We can conclude that mixtures with grain by-products can be accurately 3D-printed in various shapes, but further modifications are required to avoid undesirable shape deformation in post-processing.

Trichothecene mycotoxins are found worldwide in cereals and cereal-based products, which creates an ongoing global food security concern. Type A trichothecenes T-2 and HT-2 toxins are potent cytotoxic and immunosuppressive agents, which cause variety of adverse health effects in both humans and animals. The influence of food processing methods on these toxins is still poorly understood. In the recent years, application of cold plasma technology in food industry and agriculture is rapidly growing. This non-thermal food processing method has a high potential in solving various problems connected to microbial decontamination, and has recently been used for degradation of mycotoxins. This study investigated the influence of low pressure plasma discharge system with different work gases (oxygen, nitrogen, air, argon) on T-2 and HT-2 toxin levels in oat flour reference material within various timeframes. The plasma treatment was performed in a 0.5 L reactor, using a power source with nominal power of 6 W (2.5 kV, 25 kHz). Samples were analyzed for T-2 and HT-2 toxin concentrations before and after the treatment using the confirmatory liquid chromatography tandem-mass spectrometry (LC-MS/MS) method. The obtained results show higher degradation of T-2 after plasma treatment than of HT-2 toxin. Maximal degradation of T-2 and HT-2 toxin was achieved using nitrogen gas (38.60% and 33.53%, respectively), whereas application of argon does not significantly (p > 0.05) reduce these mycotoxins. Although the nominal plasma power in this study was insufficient to completely degrade T-2/HT-2 toxins, results indicate that cold plasma has a potential to be used as an effective physical method in reduction of mycotoxins.

High voltage gas phase plasmas are new developing techniques used for food and water decontamination [1, 2]. Still, there is a main question are the microorganisms really inactivated after the treatment or just under the stress. In this study we have examined the influence of high voltage plasma generated in the bubbles (injected air or argon-applied flow of 5 L/min) on inactivation, cells recovery, cellular leakage, proteomic analyses and transmission electron microscopy (TEM) analyses of Listeria innocua ATCC 33092 samples. Bacterial solution (200 mL) was treated in a glass reactor with a point-to-plate electrode configuration (high voltage electrode was stainless steel medical needle). Frequency of 60, 90 and 120 Hz, conductivity of solution 100 µS/cm, positive polarity and time of 5 and 10 min were chosen in order to determine their influence on listed parameters. The results of this study have showed that with a longer treatment time inactivation was higher. Complete inactivation was observed at all three frequencies with the injection of argon. Cellular leakage was determined at the 260 nm for nucleic acids and 280 nm for protein leakage. Higher leakage of proteins was detected compared to nucleic acids leakage. TEM analyses have showed that after the treatment (injected argon, 90 Hz and 10 min) membrane permeabilization occurred but not a complete disruption, as cellular macromolecules (DNA, RNA, proteins) were clearly inside the membrane wall (Figure 1). This was a proof why complete recovery of treated samples occurred. Proteomic analyses by MALDI-TOF/TOF MS have indicated overexpressed oxidative stress proteins compared to untreated sample.

High voltage electrical discharge-plasma (HVED) is a new promising technology which can be used for green extraction concept. The main point is based on different green solvents as water, ethanol, ethyl acetate, D-limonene, alphapinene for the extraction of bioactive compounds from different herbs. To define the solubility of bioactive compounds, two prediction methods can be used. COSMO-RS (Conductor-like Screening Model for Real Solvents) simulates virtual conductor environment for the molecule of interest and combines quantum chemical considerations (COSMO) and statistical thermodynamics (RS) [1]. HANSEN solubility parameters (HSP) is based on the concept that the total cohesive energy is approximated by the sum of energy densities required to overcome atomic dispersion forces, molecular polar forces and hydrogen bonds [1]. In this study two bioactive compounds (carvacrol and thymol) from oregano herb (Origanum vulgare) were chosen for COSMO-RS and HANSEN calculations for the selection of green solvents for HVED extractions. The best solvents for the extraction of carvacrol and thymol predicted by COSMO-RS are ethanol and ethyl acetate. HSP showed that good solvency will be achieved in ethyl acetate, D-limonene and alphapinene. After the selection of solvents, the main aim is to define the effectiveness of HVED treatment on the extraction of bioactive compounds from oregano.

Trodimenzionalno printanje („3D printing“) podrazumijeva proizvodne procese koji se primjenjuju s ciljem stvaranja trodimenzionalnih objekata što prehrambenoj industriji omogućuje korištenje većeg broja sirovina te poboljšanje izgleda i teksture tradicionalnih proizvoda kontrolom prehrambenih materijala na mikro- i makro- strukturnoj razini. Funkcionalna hrana se nameće kao novo polje razvoja 3D printanja u prehrambenoj industriji, jer se slaganjem posebnih receptura prilagođenih osobnim prehrambenim potrebama pojedinca razvija se i nova grana personalizirane prehrane. Zbog mogućnosti stvaranja različitih oblika, te prilagođene recepture 3D printane namirnice su praktične za konzumaciju te primjerene za specijaliziranu prehranu vojnika, astronauta, te osoba s posebnim prehrambenim zahtjevima ili poteškoćama u žvakanju i gutanju (starije osobe kojima često nedostaje raznovrsne prehrane, bolesnicima, trudnicama i maloj djeci). Jedna od glavnih prednosti ove tehnologije je smanjenje proizvedenog otpada u proizvodnji hrane, kao i maksimalno iskorištavanje sirovina te mogućnost proizvodnje jestive ambalaže i pribora za jelo. Prema dosadašnjim istraživanjima tehnologija 3D printanja hrane ima sve predispozicije za stvaranje ekološki prihvatljivih i održivih prehrambenih navika.

The main aim of plasma processing is to reduce food wastage caused by microbial spoilage as well to retain high quality of treated products. In this study, samples of apple juice, inoculated with yeasts (Saccharomyces cerevisiae and Rhodotorula sp. 74) were treated in a point- to-plate reactor type with liquid and gas discharge plasma. Samples were analysed in order to define plasma effects on organoleptic properties of fruit juices (aroma profile and sensory evaluation) as well as inactivation effects on inoculated yeasts. The most effective plasma treatment in yeast inactivation as well as in total organoleptic properties of juice was liquid discharge with argon as headspace gas.

High voltage electrical discharge-plasma (HVED) is a new nonthermal technology used for the extraction of bioactive compounds [1]. The main point is placed on the use of different “green” solvents as ethanol, propanol, α-pinene, β- myrcene, D-limonene, 2-methyltetrahydrofuran (MeTHF), cyclopentyl methyl ether (CPME) or dimethyl carbonate (DMC). To define the solubility of bioactive compounds in different “green” solvents a relatively new prediction method can be used, known as COMOS-RS. COSMO-RS (Conductor-like Screening Model for Real Solvents) simulates virtual conductor environment for the molecule of interest and combines quantum chemical considerations (COSMO) and statistical thermodynamics (RS) [2]. Bioactive compounds from oregano (Origanum vulgare), and olive leaf (Olea europaea) were chosen for COSMO-RS calculations and high voltage electrical discharge plasma extractions. The main aim is to define the effectiveness of high voltage electrical discharge plasma treatment on the extraction of essential oil from oregano and olive leaf with a “green” solvents chosen by COSMO-RS prediction method.

Mikotoksini se zbog svoje kompleksne strukture i visoke stabilnosti vrlo teško uklanjaju iz prehrambenog lanca čime predstavljaju ozbiljnu prijetnju ljudskom zdravlju. T-2 toksin i njegov glavni metabolit HT-2 predstavljaju trihotecenske mikotoksine izrazite toksičnosti za koje je dostupno vrlo malo podataka o učincima prerade hrane na njihovu prisutnost. Primjena tehnologije obrade namirnica hladnom plazmom kao nove ne toplinske metode u prehrambenoj industriji pokazala se kao učinkovita metoda u širokom spektru proizvodnih faza. Za sada malobrojna istraživanja ukazuju na potencijal hladne plazme u uklanjanju mikotoksina, pri čemu vrsta hrane i mikotoksina utječu na učinkovitost ove metode. Cilj ovog rada je ispitivanje utjecaja niskotlačne DBD hladne plazme s dušikom kao radnim plinom na učinkovitost redukcije T-2 i HT-2 toksina u uzorku zobenog brašna pri vremenima izlaganja uzorka od 10, 20 i 30 minuta. Koncentracija T-2 i HT-2 toksina prije i nakon tretmana hladnom plazmom određena je primjenom tekućinske kromatografije s masenom spektrometrijom (LC-MS/MS). Rezultati pokazuju da je uklanjanje T-2 i HT-2 toksina ovisno o trajanju tretmana hladnom plazmom, a maksimalna redukcija (38, 6%) postiže se nakon 30 minuta izlaganja. Dobiveni rezultati pokazuju učinkovitost hladne plazme u uklanjanju T-2 i HT-2 toksina, s konačnim ciljem sigurnosti hrane i zaštite zdravlja ljudi i životinja.