Natural products of plant origin, which include essential oils (EO) could be used as a growth inhibitor of pathogenic and spoilage microflora in food. The objective of this study was to determine the antibacterial and antioxidant activity of 21 EO against 10 species isolated from freshwater fish. The chemical composition of EO was determined by gas chromatography/mass spectrometry. The disc diffusion method and detection of minimum inhibitory concentration (MIC) were used for the determination of the antimicrobial activity. All the EO tested exhibited antimicrobial activity, however, EO was the most effective against spp. both according to the disc diffusion and MIC methods. The EOs of, , and showed the highest antioxidant activity of 93.86 μg, 83.47 μg, 76.74 μg and 74.28 μg TEAC/mL. Application of EO could be an effective tool for inhibition of growth of spp. on fish.

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The aim of the study was to evaluate the antimicrobial effect of sage and rosemary essential oils (EO) on microbiota of fresh chicken breast. Sample treatments were stored without packaging, vacuum-packaged, vacuum-packaged with EDTA 1.5% v/w, sage and rosemary EO treatment 0.2% v/w. Assessment of food quality was done by anaerobic plate count (APC), and Enterobacteriaceae, lactic acid bacteria (LAB) and Pseudomonas spp. counts a period of 16 days of storage at 4 ± 0.5 °C. Bacterial species were identified with a MALDI TOF MS Biotyper. Antimicrobial activity of isolates against both EO were tested. The APC varied from 2.97 log CFU/g to 6.81 log CFU/g, LAB from 2.35 log CFU/g to 3.36 log CFU/g and Enterobacteriaceae from 0.00 log CFU/g on day 0 to 4.77 log CFU/g with the highest counts on day 16 and in control unpackaged samples. Pseudomonas spp. was found only on days 0, 4, 8, and 12, with counts from 0.00 log CFU/g on day 16 to 2.89 log CFU/g on day 4 in control unpackaged samples. APC were represented by Staphylococcus and Kocuria, LAB with Lactobacillus and Enterobacteriaceae with Buttiauxella, Escherichia, Hafnia, Serratia and Yersinia. The Pseudomonas genus was represented by ten species. The best antimicrobial effect on APC, Enterobacteriaceae, LAB and Pseudomonas was achieved by application of EO. The results suggest the potential use of Salvia officinalis L. and Rosmarinus officinalis L. EOs as natural food preservatives and potential sources of antimicrobial ingredients in the food industry.

Plant oils and fats are important and necessary components of the human nutrition. They are energy source and also contain fatty acids - compounds essential for human health. The aim of this study was to evaluate nutritional quality of selected plant oil - olive, rapeseed, pumpkin, flax and sesame; based on fatty acid composition in these oils. Fatty acids (MUFA, PUFA, SFA) were analyzed chromatography using system Agilent 6890 GC, injector multimode, detector FID. The highest content of saturated fatty acids was observed in pumpkinseed oil (19.07%), the lowest content was found in rapeseed oil (7.03%), with low level of palmitic and stearic acids and high level of behenic acid (0.32%) among the evaluated oils. The highest content of linoleic acid was determined in pumpkinseed (46.40%) and sesame oil (40.49%); in these samples was also found lowest content of α-linolenic acid. These oils have important antioxidant properties and are not subject to oxidation. The richest source of linolenic acid was flaxseed oil which, which is therefore more difficult to preserve and process in food industry. In olive oil was confirmed that belongs to the group of oils with a predominantly monosaturated oleic acid (more than 70%) and a small amount of polysaturated fatty acid. The most commonly used rapeseed oil belongs to the group of oils with the medium content of linolenic acid (8.76%); this oil also showed a high content of linoleic acid (20.24%). The group of these essentially fatty acids showed a suitable ratio ∑n3/n6 in the rapessed oil (0.44).

The current study was designed to enhance the functionality of white bread by replacement of wheat flour with different levels (1%, 2%, 5%, and 8%) of grape seeds micropowder (GSMP) with nanosized particles (10 µm). Chemical composition of GSMP, volume and sensory attributes, evaluated with the panel of evaluators and an electronic nose (e-nose) and an electronic eye (e-eye) were investigated in the tested breads. It has been found out that GSMP contained appreciable amounts of flavonoids including catechin, epicatechin, gallic acid and minerals especially, Ca, K and Mg. The data from rheological analysis showed that the addition of GSMP (mainly at 5% and 8% levels) to the wheat flour had a positive effect on dough manifesting with rheology by increased dough stability. The volume of the experimental breads (above 1% concentration) was demonstrably declined (P < 0.0001) in comparison with the control bread. Sensory rating revealed that the bread fortified with 1% GSMP was judged by the consumer panelists as the most acceptable with the highest scores for all quality attributes which was also confirmed by the data of e-nose and e-eye. Our results suggest for the first time that 1% GSMP addition appears to be a promising functional ingredient to improve bread with required qualitative and sensory properties.