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How do sous-vide treatment and herb spices addition improve sensory acceptance and antimicrobial attributes of organic oyster mushrooms (Pleurotus ostreatus)?
No full textSensory and physical properties of organic oyster mushrooms (Pleurotus ostreatus) prepared by the sous-vide culinary method (50-90 degrees C, 10 ') were investigated and compared with the cooking method (80 degrees C, 30-60 ') to analyze the effects of different temperature and time regimes. To promote organic oyster mushroom's nutritional benefits and improve its taste, oregano and thyme were added in different percentages, and mushrooms were exposed to sous-vide treatments at 60 degrees C for 20 ' and 30 '. Sensory evaluation was focused on testing spices intensity, likeability, and recognizability with principal component analysis employed. While the likeability scores and color changes were higher for those with higher thyme content in the mixture, the antibacterial results showed the highest effect of oregano, proving certain positive effects and emphasizing the research's importance. As an added value of the research, the mixture concentrations of sous-vide vacuumed pouches containing spices and mushrooms, that is, sous-vide pure juice extracts were analyzed for the first time for antibacterial activity. The research highlights the sensory improvement of mushrooms using the convenient treatment and adding selected spices, altogether multiplying their health benefits by preserving beneficial compounds. Novelty impact statement Sous-vide culinary method, as an innovative choice in the world of gastronomy, gives the possibility to adjust treatment conditions and enables control of changes associated with the physical properties of mushrooms. Concerning the importance of living a healthy lifestyle, the fact that this method provides the ability to preserve bioactive compounds in well-known healthy foods, such as mushrooms, widens the additional importance of its application. The research highlights the sensory improvement of mushrooms using convenient heat treatment and adding selected spices generally used in traditional and world-known cuisine and altogether multiply their health benefits by preserving beneficial compounds
Physicochemical parameters and phenolic content of honey produced from the area of Tara region
No full textSeasonal Variations in Essential Oil Composition of Immortelle Cultivated in Serbia
No full textOur previous research has proven that the immortelle (Helichrysum italicum) essential oil (EO) grown in Serbia possesses respectable biological potential and desirable composition of volatile compounds with the potential for a wide range of applications in the food, cosmetics, and pharmaceutical industries. Within this study, the impact of seasonal variations (temperature, precipitation, and insolation) during three successive years (2017, 2018, and 2019), on the volatile profile of gamma-curcumene + ar-curcumene immortelle chemotype was determined. Steam distillation was utilized to extract EO from the plant material, followed by chromatographic mass spectrometric analysis revealing 50 volatile compounds. A multiple linear regression model was developed, and principal component analyses were conducted to deliver detailed information regarding the prediction, component profile, and parallel contents of active compounds of the immortelle EO. Under Serbian agro-ecological conditions, with appropriate harvest method, immortelle can achieve two harvests per year: the first in July, and the second in August. The gamma-curcumene + ar-curcumene chemotype usually occurs as the dominant chemotype in the region of the ex-Yugoslavia countries. This chemotype probably developed as an adaptation to climatic conditions, and spring and summer precipitation positively influenced curcumene accumulation in plants. Such a phenomenon was especially noticeable in the first harvest
Analysis of mass transfer rate and efficiency of osmotic dehydration of wild garlic
No full textThe availability period of fresh wild garlic is very limited, only during the spring season. After harvest, the leaves quickly lose their sensory, nutritious and functional properties. The stability and availability of this valuable herb material can be extended by adequate drying technique. The aim was to evaluate the influence of used osmotic solution, process duration, temperature and mixing on the mass transfer rate and the efficiency of process on wild garlic. The paper describes a study of osmotic dehydration of wild garlic (Allium ursinum L.) in sugar beet molasses and aqueous solution of sodium chloride and sucrose, at three different temperatures (20, 35, and 500C), with and without manual stirring in every 15 minutes. For this purpose, rate of water loss-RWL, rate of solid gain-RSG, rate of weight reduction-RWR and dehydration efficiency index-EI, were determined after 1, 2.5, and 4 hours of dehydration. In order to follow the mass transfer during the process, three key process variables were measured: moisture content, change in weight and change in dry matter, in accordance with Official Methods of Analysis (AOAC). Based on the obtained parameters RWL, RSG, RWR and EI were calculated. Principal component analysis (PCA) was applied to separate the samples according to the process parameters and characterize the observed samples. Higher values of the observed parameters was achieved when the process was performed with agitation. Mass transfer was the most intensive at the beginning of the process, at temperature of 500C. RWL, RSG, RWR and EI decreased continuously from the first to the fourth hour, and after 2.5 hours showed a tendency to slow down. The highest value of EI was obtained by using molasses as osmotic solution, at 200C, after 2.5 hours of process, performed with agitation (5.59), and without agitation (5.27), which was also observed on the PCA biplot. Mass transfer was the most intensive at the beginning of the process, decreased continuously from the first to the fourth hour, and after 2.5 hours showed a tendency to slow down. Therefore, processing time can be limited to 2.5 hours
Mineral content after osmotic treatment of nettle leaves (urtica dioica l.)
No full textOsmotic treatment (OT) is an important method for preserving food, which involves partial water removal from samples immersed in hypertonic solutions. This study aimed to investigate the effects of OT in two different solutions on nettle leaves’ mineral content. Nettle leaves were dehydrated in sugar beet molasses (80%) and an aqueous solution of sodium chloride and sucrose, at 350C and 500C for 30, 60 and 90 min. Mineral content (Ca, Mg, Na, K, Fe, Cu Zn, Mn and Co) was determined in fresh and dehydrated leaves. The basic chemical composition of nettle leaves before and after the OT was determined based on the following methods: Content of Fe, Cu and Zn was determined by the method FINSLab-5.4-3M-004/13; Determination of: Pb, Cd, As, Zn, Cu, Fe, Sn, and Cr in food by atomic method absorption spectrometry (AAS); Content of: Ca, K, Mg, Na, Mn, and Co in fresh and OT samples was determined using the standard SRPS EN ISO 6869: 2008, Animal feed, and determination of: Ca, Mg, Mn, K, Na and Co contents in food by atomic absorption spectrometry (AAS). There was a slight decrease in mineral content in the samples dehydrated in a clear solution, compared to molasses, where all samples showed an increase in monitored minerals after OT. The highest values of monitored minerals were achieved by OT of nettle leaves in molasses solution, after 90 minutes, at 500C, especially Fe (from 30.989 ± 0.062 mg/100g i.s. to 98.627 ± 1.674 mg/100g i.s.) and K (from 50.752 ± 1.226 mg/100g i.s. 97.903 ± 0.905 mg/100g i.s.). After the treatment, the content of Na in all samples was increased. It can be concluded that the content of Ca, Mg, K, Fe, Cu, Zn, Mn and Co increased in nettle leaves dehydrated in sugar beet molasses, while in the samples dehydrated in NaCl and sucrose solution opposite trend was observed
Comparison of Nutritional Profiles of Super Worm (Zophobas morio) and Yellow Mealworm (Tenebrio molitor) as Alternative Feeds Used in Animal Husbandry: Is Super Worm Superior?
No full textSimple Summary Currently, the food industry is facing numerous problems related to the increase in the global human population resulting in an increase in the demand for livestock. Animal feed production, as the chain leader of food production, needs to reduce the utilization of commonly used feeds, such as soybean meal and fish meal, and replace them with more sustainable ones. The utilization of insects as an alternative sustainable feed in the upcoming years can be one of the solutions. Optimization of rearing conditions, which includes the choice of insect species, time of harvest, and proper insect diet, is highly desirable for wider insect mass production. Along with the optimization of rearing conditions, insect producers will be able to obtain the desirable biomass and nutritive composition of insect products with the minimization of production costs. With their desirable nutritional composition, super worms could be used in extended mass production. Additionally, in animal feed production, super worms and yellow mealworms can be used as a nutritional source and a promising alternative to traditional feed ingredients. However, the optimization of the rearing conditions is needed for wider use in the animal feed industry. Edible insects are acknowledged as a valuable nutritional source and promising alternative to traditional feed ingredients, while the optimization of rearing conditions is required for their wider utilization in the animal feed industry. The main goal of this study was to compare and optimize the rearing conditions of the two species' larvae and identify the most favorable nutritive composition of the full-fat larval meal. For that purpose, Tenebrio molitor (TM) and Zophobas morio (ZM) were reared on three different substrates and harvested after three time periods. An artificial neural network (ANN) with multi-objective optimization (MOO) was used to investigate the influence between the observed parameters as well as to optimize and determine rearing conditions. The optimization of the larval rearing conditions showed that the best nutritive composition of full-fat larval meal was obtained for ZM larvae reared on a mixture of cabbage, carrot and flaxseed and harvested after 104 days. The best nutritive composition contained 39.52% protein, 32% crude fat, 44.01% essential amino acids, 65.21 mg/100 g Ca and 651.15 mg/100 g P with a favorable ratio of 1.5 of n6/n3 fatty acids. Additionally, the incorporation of flaxseed in the larval diet resulted in an increase in C18:3n3 content in all samples
Laser surface texturing of Ti/Cu/Ti and Ti/Cu/Zr/Ti multilayers thin films
No full textIn this study, the design of surface pattering with the co-existence of micrometer and nanometer features was carried out to improve the arrayed surface structures on Ti/Cu/Ti and Ti/Cu/Zr/Ti multilayer thin films by picosecond laser processing. The novel composite structure consisted of two layers of Ti and subsurface distributed Cu and Zr layers (thickness of 10 nm) were deposited by ion sputtering on Si substrate to the total thickness of 300 nm. The changes in the composition, surface morphology, and wetting properties after laser modification was monitored by Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM-EDS), optical profilometry, and wettability measurements. It was found that laser irradiation can induce the melting of material with the formation of wrinkled periodic structures at the edges of the laser spots in both systems as a consequence of the hydrodynamic effects. Another interesting result was that the periodic structure in form of LSFL (low spatial frequency LIPSS) ripples was numerous but slightly pronounced in Ti/Cu/Zr/Ti, due to the presence of the Zr component as an ultra-thin subsurface layer, which most likely favored creating LIPSS. Such laser texturing has been used in the biomedical field as a method of developing surface topography, coated with oxides to potentially improve cell response via suitable surface wetting for a biological system
Photophysical and Primary Self-Referencing Thermometric Properties of Europium Hydrogen-Bonded Triazine Frameworks
No full textLanthanide hydrogen-bonded organic frameworks (LnHOFs) are recently emerging as a novel versatile class of multicomponent luminescent materials with promising potential applications in optics and photonics. Trivalent europium (Eu3+) incorporated polymeric hydrogen-bonded triazine frameworks (PHTF:Eu) have been successfully obtained via a facile and low-cost thermal pyrolysis route. The PHTF:Eu material shows a porous frame structure principally composed of isocyanuric acid and ammelide as a minor constituent. Intense red luminescence with high colour-purity from Eu3+ is obtained by exciting over a broad absorption band peaked at 300 nm either at room or low temperature. The triazine-based host works as excellent optical antenna towards Eu3+, yielding similar to 42% sensitization efficiency (eta(sens)) and an intrinsic quantum yield of Eu3+ emission (Phi(Eu)) as high as similar to 46%. Temperature-dependent emission studies show that PHTF:Eu displays relatively high optical stability at elevated temperatures in comparison to traditional inorganic phosphors. The retrieved activation energy of 89 meV indicates that thermal quenching mechanisms are attributed to the intrinsic energy level structure of the metal-triazine assembly, possibly via a thermally activated back transfer to ligand triplet or CT states. Finally, by using an innovative approach based on excitation spectra, we demonstrate that PHTF:Eu can work as a universal primary self-referencing thermometer based on a single-emitting center with excellent relative sensitivity in the cryogenic temperature range
Cinnamon essential oil and its emulsion as efficient antibiofilm agents to combat Acinetobacter baumannii
No full textAcinetobacter baumannii is an emerging nosocomial pathogen resistant to a wide spectrum of antibiotics, with great potential to form a biofilm, which further aggravates treatment of infections caused by it. Therefore, searching for new potent agents that are efficient against A. baumannii seems to be a necessity. One of them, which has already been proven to possess a wide spectrum of biological activities, including antimicrobial effect, is cinnamon essential oil. Still, further increase of antibacterial efficacy and improvement of bioavailability of cinnamon oil is possible by emulsification process. The aim of this study was comparative analysis of cinnamon essential oil and its emulsion against biofilm forming A. baumannii clinical isolates. Furthermore, the investigation of toxicological aspects of possible applications of essential oil and emulsion was done as well. Gas chromatography-mass spectrometry of essential oil indicated trans-cinnamaldehyde as the most abundant component. The cinnamon emulsion was synthesized from cinnamon essential oil by combining modified low- and high- energy methods. Synthesized emulsion was characterized with Fourier-transform infrared spectroscopy and photon correlation spectroscopy. Both substances exhibited significant antibacterial (minimal inhibitory concentrations in the range 0.125-0.5 mg/ml) and antibiofilm effects (inhibitions of formation and reduction of pre-formed biofilm were 47-81 and 30-62%, respectively). Compared to essential oil, the efficacy of emulsion was even stronger considering the small share of pure oil (20%) in the emulsion. The result of biofilm eradication assay was confirmed by scanning electron microscopy. Even though the cytotoxicity was high especially for the emulsion, genotoxicity was not determined. In conclusion, strong antibacterial/antibiofilm effect against A. baumannii of the cinnamon essential oil and the fact that emulsification even potentiated the activity, seems to be of great significance. Observed cytotoxicity implicated that further analysis is needed in order to clearly determine active principles being responsible for obtained antibacterial/antibiofilm and cytotoxic properties
