Laurel, Laurus nobilis L. is an evergreen plant belonging to the Lauraceae family, native to Southern Europe and the Mediterranean area. This is the first report on the composition and bioactivity of laurel essential oil (EO) from Bulgaria. The oil yield was 0.78%, 0.80%, and 3.25% in the fruits, twigs, and leaves, respectively. The main constituents in the fruit EO were 1,8-cineole (33.3%), α-terpinyl acetate (10.3%), α-pinene (11.0%), β-elemene (7.5%), sabinene (6.3%), β-phellandrene (5.2%), bornyl acetate (4.4%), and camphene (4.3%); those in the twig EO were 1,8-cineole (48.5%), α-terpinyl acetate (13.1%), methyl eugenol (6.6%), β-linalool (3.8%), β-pinene (3.4%), sabinene (3.3%) and terpinene-4-ol (3.3%); and the ones in the leaf EO were 1,8-cineole (41.0%), α-terpinyl acetate (14.4%), sabinene (8.8%), methyl eugenole (6.0%), β-linalool (4.9%), and α-terpineol (3.1%). The antibacterial and antifungal properties of laurel EOs were examined according to the agar well diffusion method. The leaf EO showed antibacterial and antifungal activities against almost all strains of the microorganisms tested, whereas the twig EO was only able to inhibit Staphylococcus aureus. Pseudomonas aeruginosa АТСС 9027 and Escherichia coli ATCC 8739 were the bacterial strains that showed the highest resistance to the laurel EO. The results can benefit the EO industry and biopesticide development.

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The aim of the present study was to evaluate the possibilities for using date fruit from the Kingdom of Saudi Arabia in the formulation of a novel snack bar while replacing the used honey with date paste. The technological, textural, microbiological and sensory qualities of the obtained food products were evaluated during storage for 12 days after their production. Date palm fruit in the form of date paste was used as an ingredient in the composition of the new snack bars that also included nuts and dried fruits. Five formulations were prepared: a control bar, snack bar with 40% date paste, snack bar with 50% date paste, snack bar with 60% date paste, and snack bar with 70% dates paste. The resulting date paste’s textural characteristics supported the bonding potential of the food system and gave a sweet taste to the final product. The formulations containing 50% date paste presented the highest overall acceptability and were the formulation with the best sensory characteristics. Thus, the addition of date paste in snack bars would be a good option to develop a functional product that contributes to rational nutrition principles. The obtained values in the current study confirmed the technological and functional potential of date fruit as a product that can find adequate application in the composition of foods with functional properties.

The search for fast and environmentally safe methods of fighting fires has been a particularly important topic in recent years. Many academic centres are conducting research on the use of Deep Neural Networks to detect flames. One of the most promising is the acoustic method of extinguishing flames. In theory, an acoustic extinguisher can be applied to extinguish fires of different classes because acoustic waves pass through solids, liquids, and gases. In principle, the technology described in the article can be used to extinguish B- and C-class fires when gases or liquids are burning. Until now, the known studies have been conducted only for low-power acoustic extinguishers. Therefore, there is a need to fill a theoretical and practical gap in this respect (scientific novelty). The result of the activities is the development of new techniques for extinguishing flames with the use of Deep Neural Networks, and then extinguishing flames using a high and very high power loudspeaker applied to the acoustic extinguisher. The main aim of this paper is to present the possibilities of using Deep Neural Networks to detect fires, as well as the results of research on the extinguishing of flames with the use of square waveforms with Amplitude Modulation (AM) for several frequencies, which is also a scientific novelty, including the minimum acoustic power and sound pressure level as a function of a distance from the output of the acoustic system. On this basis, it became possible to determine the minimum power delivered to the extinguisher and the minimum sound pressure level that causes the extinguishing effect at given input parameters.

Introduction. Representatives of the Lamiaceae family are widely used in the food industry as they are characterized by a high content of aromatic compounds. Materials and methods. It was evaluated the chemical composition and antibacterial activity of essential oils of garden thyme (Thymus vulgaris L.), rosemary (Rosmarinus officinalis L.), spearmint (Mentha spicata L.), and sweet basil (Ocimum basilicum L.). Results and discussion. The percentage ratio of volatile components obtained by GC-MS analysis of essential oil from garden thyme contains: thymol (37.90%) and γ-terpinene (19.44%). It has been determined eucalyptol (19.89%) and camphor (16.86%) in the essential oil of rosemary and carvone (50.23%) and limonene (13.90%) in spearmint oil, respectively. The differences in the quantitative and qualitative composition of essential oils and their aromatic components in relation to the previous researches may be probably due to different environmental and genetic factors, different chemotypes and the nutritional status of the plants as well as other factors that can influence the oil composition. Escherichia coli was the most susceptible bacterium strain. The essential oils of spearmint and rosemary possessed the most pronounced antibacterial activities against Escherichia coli (with inhibition zone: 32.00 mm and 30.00 mm). Conclusions. The results obtained provide a basis for a thorough examination of the chemical composition and antimicrobial properties of various representatives of Lamiaceae family with a view to a wide usage in food technology.

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Introduction. The study was carried out to determine the chemical composition and biological activity of false acacia flowers and their products (concrete and syrups) grown in Bulgaria. Materials and methods. Concrete was obtained by extraction with n-hexane and its chemical composition was determined by GC-MS. Syrups with different concentrations have been obtained and their polyphenols content, antimicrobial and antioxidant activity were established. Result and discussion. The yield of concrete was 1.06% and the major constituents of the concrete are as follows: n-nonacosane (25.18%), n-heptacosane (20.10%), α-linolenic acid (5.97%), n-pentacosane (4.98%), palmitic acid (4.92%), diisooctyl phthalate (4.05%), hexahydrofarnesyl acetone (3.86%), linoleic acid (3.64%), isopropyl myristate (3.47%), and n-hentriacontane (3.39%). The total aliphatic hydrocarbons constituted the highest percentage of the component of the concrete constituting 61.50%. The minerals identified as biggest content in the tested samples of false acacia flowers are nickel, copper, calcium and chromium. Higher values of phenolic compounds in the flowers (0.77 mg GAE/mL) than those of the syrup 60 °Brix (0.06 mg GAE/mL) and R. pseudoacacia syrup 70 °Brix (0.14 mg GAE/mL) were found. The syrup samples exhibit antimicrobial properties against foodborne pathogenic bacteria as Salmonella, E. coli and L. monocytogenes. Conclusion. Based on the chemical and biochemical properties of false acacia flowers, it could be recommended as a potential raw material for food, pharmaceutical and cosmetic products.

The aim of the present study was to investigate the physicochemical and microbiological profile of indigenous sheep’s milk with the potential for the production of artisanal cheese. The data showed the changes in lactation stages (between April and August) up to 2 hours following manual milk production. The quality of raw milk in the production of brined cheese using traditional technology was assessed. The amount of dry matter was21.36% in April and 19.85% in August at the end of lactation. The fat content from April to August was between 8.62% and 8.03%, preserving the values reported. The protein composition of raw milk varied between 5.52 – 6.61%. In the microbiological evaluation of raw sheep’s milk after milking (35.3°C), the total microbial contamination was in the range of 1.3 x 106 to 1.4 x 106 CFU/mL under current conditions. The results obtained in this paper give rise to more in-depth studies on the application of raw sheep’s milk in the production of traditional artisanal cheeses.