This paper describes carotenes extraction from carrot under different conditions involving different temperatures, treatment of samples, and solvents (ethanol, 2-propanol). Carrot roots (<I>Daucus carota</I> L. cv. Nevis F1) were tested for the extraction yields of carotenes at temperatures 20°C, 40°C, and 60°C, the samples having been examined after harvest, after cold storage (stored at 5°C), and after freezing (–18°C). In connection with the technology of the carotenoid concentrate production from carrots, it was found that the solubility and yield of carotene from carrot depend on the temperature and the time of extraction as well as the treatment of the sample. It was revealed that the best extraction efficiency was achieved with the samples treated by freezing and using the extraction 60°C for 2–4 hours. Higher temperatures caused an increase in the carotenoid concentrations. The carrot variety Nevis F1 and the extraction at 60°C were used for the model production of carotenoid concentrate.

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Contamination by microscopic fungi and mycotoxins in different bee pollen samples, which were stored under three different ways of storing as freezing, drying and UV radiation, was investigated. During spring 2009, 45 samples of bee-collected pollen were gathered from beekeepers who placed their bee colonies on monocultures of sunflower, rape and poppy fields within their flying distance. Bee pollen was collected from bees' legs by special devices placed at the entrance to hives. Samples were examined for the concentration and identification of microscopic fungi able to grow on Malt and Czapek-Dox agar and mycotoxins content [deoxynivalenol (DON), T-2 toxin (T-2), zearalenone (ZON) and total aflatoxins (AFL), fumonisins (FUM), ochratoxins (OTA)] by direct competitive enzyme-linked immunosorbent assays (ELISA). The total number of microscopic fungi in this study ranged from 2.98 ± 0.02 in frozen sunflower bee pollen to 4.06 ± 0.10 log cfu.g(-1) in sunflower bee pollen after UV radiation. In this study, 449 isolates belonging to 21 fungal species representing 9 genera were found in 45 samples of bee pollen. The total isolates were detected in frozen poppy pollen 29, rape pollen 40, sunflower pollen 80, in dried poppy pollen 12, rape pollen 36, sunflower 78, in poppy pollen after UV radiation treatment 54, rape 59 and sunflower 58. The most frequent isolates of microscopic fungi found in bee pollen samples of all prevalent species were Mucor mucedo (49 isolates), Alternaria alternata (40 isolates), Mucor hiemalis (40 isolates), Aspergillus fumigatus (33 isolates) and Cladosporium cladosporioides (31 isolates). The most frequently found isolates were detected in sunflower bee pollen frozen (80 isolates) and the lowest number of isolates was observed in poppy bee pollen dried (12 isolates). The most prevalent mycotoxin of poppy bee pollen was ZON (361.55 ± 0.26 μg.kg(-1)), in rape bee pollen T-2 toxin (265.40 ± 0.18 μg.kg(-1)) and in sunflower bee pollen T-2 toxin (364.72 ± 0.13 μg.kg(-1)) in all cases in frozen samples.

Frančáková H., Líšková M., Bojňanská T., Mareček J. (2012): Germination index as an indicator of malting potential. Czech J. Food Sci., 30: 377-384.The malting industry requires malt with a high extract yield, high levels of enzyme activity, and good modification to manufacture beer of excellent quality. The basic raw material for the beer production is the malting barley whose quality is of primary significance. Therefore, barley must be able to germinate vigorously and be post-harvest mature to meet these requirements. We find out to what extent barley physiological parameters influence the changes of malt technological parameters during post-harvest storage. The malt technological parameters investigated were the extract, relative extract at 45°C, Kolbach index, apparent final attenuation, friability, and wort β-glucan in relation to the germination energy and germination index. On the basis of the results obtained, it was found out that the germination index is the most suitable physiological parameter in view of the correlations with malt technological parameters, mainly the extract (r = 0.57) and relative extract at 45°C (r = 0.77). The germination index could be therefore used in the malting industry as a suitable indicator of the malting potential.

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).

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Due to the content of biologically active substances, sea buckthorn (Hippophae rhamnoides L.) has become the object of great interest of both, experts and the general public. It is appreciated particularly for the high content of vitamins and other biologically active substances, not only in berries but also in leaves and bark. The aim of the study was to evaluate the nutritional quality of sea buckthorn juice prepared from different varieties of sea buckthorn based on the content of total carotenoids, polyphenols and antioxidant activity. In this study we used varieties Hergo, Tytti, Vitaminaja, Raisa, Askola, Dorana, Slovan, Leikora, Bojan, Terhi and Masličnaja. Content of different components was quantified using spectrophotometry. The total carotenoids content expressed as β-carotene content in juice ranged from 50.63 mg.100 g-1 DM to 93.63 mg.100 g-1 DM, the highest content was in variety Askola and the lowest one in Terhi. Total polyphenols content determined by Folin-Ciocalteu method ranged from 13.03 mg GAE. dm-3 DM to 25.35 mg GAE. dm-3 DM. The highest content was identified in juice of variety Dorana and the lowest one in Raisa. The antioxidant activity quantified by the FOMO method ranges from 45.11 g AA. dm-3 DM to 108.77 g AA. dm-3 DM. The highest antioxidant activity was determined in juice of Dorana and the lowest in variety Bojan

Carotenes Content in Carrot Roots (Daucus carota L.) as affected by Cultivation and Storage The influence of area, variety, year and storage on β-carotene content and dry matter content of selected carrot varieties were tested. Carrot roots of four varieties were examined during two years period (2002-2003), cultivated under different climatic and soil conditions in three areas of Slovakia - Nitra, Komárno and Prusy. Carrot varieties (Nevis F1, Idaho F1, Florida F1, Kathmandu F1) showed the greatest mean content of β-carotene (23.25 mg·100 g-1) in Nitra area, year 2003. Irrigation showed negative influence on β-carotene content. The highest content of β-carotene showed variety Florida F1 (26.3 mg·100 g-1). Mean higher contents of dry matter were determined in the year 2003 compared to the year 2002. Loss of β-carotene during carrot storage was observed higher in the cellar than in the cold storage. Mean loss of β-carotene in dry matter for cold storage was 13.57-14.28%, compared to cellar 20-27.3%.