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Representative straw samples from various cereals were analysed to determine their chemical composition and calorific value. It was found that the chemical composition data given in previous feeding tables can be applied to characterise modern varieties, as only the crude fat contents of oats and winter wheat were significantly higher than the available reference data, while the ash contents were lower. The calorific value of cereal straw was equal to or in some cases greater than that of energy grass, so cereal straw could be competitive with energy grass, due to its large cultivation area and the properties and value of its by-products.

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under the influence of the prognosticated climatic changes, the increasing rate of degradation and the extension of uncultivated lands, it is expected that the dominance of some C4 plants will increase. Bermuda grass (Cynodon dactylon) is the most common C4 species in Hungary. The chemical composition of Cynodon dactylon and its substrate was investigated on 3 soil types (Arenosol, Solonchak soil and a waste place) typical of the country. It was established that in comparison with other perennial C4 grasses (Andropogon ischaemum, Chrysopogon gryllus, Cleistogenes serotina) the total element content of Cynodon dactylon was the highest. A detailed quantitative and qualitative knowledge of the chemical components of C4 plants could help to determine the expected changes in the chemical composition of the uppermost soil layer and in its mineralization dynamics on areas dominated by these plants. As a result of the expansion of Cynodon dactylon the element concentration and the chemical composition of the soils might change, thus influencing successional processes as well.

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Pleurotus djamor from Yucatan State, Mexico was compared with a local variety of P. ostreatus , in terms of chemical composition and amino acid profile. No differences were found (P=0.55) in crude protein content of P. djamor and P. ostreatus (20.2±0.15 vs. 20.3±0.16 g/100 g DM., respectively). P. ostreatus had a lower fiber and fat content (P<0.05). No difference was found in ash content (P>0.05). P. ostreatus has a higher proportion (P<0.05) of valine, isoleucine, phenylalanine, aspartate and alanine while P. djamor had higher proportion (P<0.05) of proline and glutamate, no difference was found in the remaining amino acids. Both species had a high proportion of aspartate and glutamate. In general, the human amino acid requirements for adults are satisfied, however, leucine and lysine might become limiting. It was concluded that P. djamor can be included in human diet in similar fashion as P. ostreatus .

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Acta Alimentaria
Authors:
A. Mouwakeh
,
P. Radácsi
,
ZS. Pluhár
,
É. Németh Zámboriné
,
G. Muránszky
,
CS. Mohácsi-Farkas
, and
G. Kiskó

Nigella sativa L. (black cumin) is well known for its benefits in the field of traditional medicine. The aim of this study was to determine the chemical composition and investigate the antimicrobial activity of cold pressed oil (CO) and essential oil (EO) of Nigella sativa L. on food-borne pathogenic and spoilage bacteria. The microdilution method was used to determine the minimal inhibitory concentration (MIC) of Nigella sativa crude oil (CO) and essential oil (EO) against 4 Gram-positive (Bacillus cereus, Bacillus subtilis, Staphylococcus aureus, and Listeria monocytogenes) and 3 Gram-negative (Salmonella Hartford, Pseudomonas aeruginosa, and Escherichia coli) foodborne pathogenic and spoilage bacteria occurring in food products. Total fatty acid composition of CO was analysed by GLC, while the EO was analysed by GC-MS to detect its active compounds. The results showed that the major fatty acid of CO was palmitic acid (C16:0), as saturated fatty acid, however, linoleic acid (C18:2) was the main unsaturated fatty acid. The major compounds of the EO were p-cymene and thymoquinone. The inhibition on all tested bacteria of EO was 10 times higher than of CO, and the lowest concentration value was observed in case of Bacillus subtilis (0.003%). Hence, results reinforce the ambition to apply Nigella sativa oils in food as natural preservative.

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The feasibility of NIR spectroscopy for determining chemical composition of goose fatty liver was studied. The spectra of 50 fresh, homogenized liver samples (ether extract content EE=53.2, SD=4.87%) were taken between 1100 and 2500 nm in reflectance mode, then the chemical composition and the fatty acid profile was measured (gas chromatography). Calibration equations were developed using modified partial least-squares regression. The R 2 value in estimation of DM, CP and total EE were 0.72, 0.63 and 0.81, respectively. For the major fatty acids (oleic, palmitic and stearic acid, 51.4, 25.8 and 15.5% of total) the R² values were 0.94, 0.93 and 0.16. The estimation of the total saturated fatty acid (SAT) proportion and the so-called unsaturation index (UI) value was effective (R 2 =0.81 and 0.79, respectively). The paper demonstrates the usefulness of the NIRS method as a fast and solvent free alternative of liver qualification. For practical purposes a larger number of fatty liver samples are needed.

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Acta Alimentaria
Authors:
I. Saoud
,
L. Hamrouni
,
S. Gargouri
,
I. Amri
,
M. Hanana
,
T. Fezzani
,
S. Bouzid
, and
B. Jamoussi

The chemical composition, phytotoxic and antifungal activities of the essential oils isolated by hydrodistillation from the aerial parts of Tunisian thyme were evaluated. In order to find best results, different variables (i.e. provenance and phase of plant development) were considered. The chemical composition analysed by gas chromatography/mass spectrometry (GC/MS) revealed variability among provenances displaying interesting chemotypes and that carvacrol (63–84%), limonene (5–10%), δ-terpinene (0–7%), and β-myrcene (0–7%) were the main components. Antifungal ability of Thymus capitatus essential oils was tested by disc agar diffusion against five phytopathogenic fungi: Fusarium avenaceum, F. culmorum, Microdochium nivale var. nivale, Alternaria sp., and Bipolaris sorokiniana. High antifungal activity was observed for the essential oil isolated at the post-flowering development phase for the Bekalta provenance. There was no difference in the antifungal activities of oils isolated at the flowering phase from the other provenances. Thyme essential oils showed high level of weed-killer activity as well against Sinapis arvensis.

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The aim of the study was to compare the quality of edible parts of three experimental groups of carp, i.e. pure line of Přerov scaly carp (PS), hybrid line of Přerov scaly carp and northern mirror carp (PS×M72), the hybrid line of Přerov scaly carp and Ropsha scaly carp (PS×ROP), with the quality of edible parts of control hybrids of Hungarian and northern mirror carp (M2×M72) in harvest size (K 3 ). The chemical composition of edible parts of the experimental groups of carp (PS, PS×M72, PS×ROP) was comparable with that of the control group (M2×M72). The highest fat content (89.8±1.94 g kg −1 ) was found in the fillet of PS×ROP hybrids (P<0.05). Of EAA sum (48.54±0.31%) in the fillet of PS×ROP hybrids, Lys (9.17±0.47%) and Leu (8.28±0.49%) were the most abundant. In comparison with organs, their fillet contained more His (4.38±0.34%, P<0.01), the ovaries more Val (11.65±0.37%, P<0.01) and testes more Ile (8.13±0.53%, P<0.01), Lys (11.70±0.63%, P<0.01) and Arg (10.44±0.27%, P<0.01). In the hepatopancreas of PS×ROP hybrids Phe (4.86±0.25%, P<0.05) was the most abundant. The fillet of PS×ROP hybrids contained SFA sum (21.37±0.46%), MUFA sum (64.20±0.57%) and PUFA sum (14.56±0.34%) in the ratio of 1:3:0.7. Of the fatty acids PUFA n-3 sum (2.39±0.09%), the most abundant in the fillet of PS×ROP hybrids was the essential linolenic acid C18:3n-3 (0.86±0.09%) and the eicosapentaenic acid C20:5n-3 (0.69±0.09%) and the docosahexaenic acid C22:6n-3 (0.35±0.02%). The PUFA n-6/n-3 ratio in the fillet of PS×ROP hybrids was 3.25±0.18. The quality of edible parts of PS×ROP hybrids was comparable with that of commercially farmed M2×M72 mirror carp. From the point of view of chemical evaluation of the quality of edible parts, PS×ROP hybrids can be recommended for commercial farming in aquacultures.

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The influence of seasonal variations on the chemical composition and composition of fatty acids in five commercially important freshwater fish species from the Danube: white bream, bream, vimba, zope, and Prussian carp, during May, July and September was determined. Changes in the chemical composition of meat of all examined species had the same tendencies. Water and protein content in the meat decreased, while fat content increased. The most frequent fatty acids in the meat of all the examined fish were the following: 18:1 n-9 (oleic), 16:0 (palmitic), 16:1 (palmitoleic), 18:2 n-6 (linoleic), 20:1 (eicosenoic), 20:5 n-3 eicosapentaenoic acid (EPA), 20:4 n-6 arachidonic acid and 22:6 n-3 docosahexaeonic acid (DHA). The content of saturated fatty acids (SFA) ranged from 25.03% to 32.43% and displayed a tendency to increase during the observed period. The total content of the n-6 group in the meat of Prussian carp was higher than in other species, which was probably a consequence of specific diet. The total content of n-3 fatty acids in the meat of white bream, bream, vimba and zope was the highest in May, and it declined during July-September. We can conclude that the meat of white bream and vimba contains high nutritional values in terms of EPA and DHA content. The n-3/n-6 ratio was also very favourable: 0.9 to 2.0 in the meat of white bream, bream, vimba and zope, with a clear downward tendency in the observed period.

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1021 1026 Elfversson, C., Andersson, A.A., Åman, P., Regnér, S. 1999. Chemical composition of barley cultivars fractionated by weighing, pneumatic classification, sieving, and

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chemical composition may significantly vary according to the plant source, climatic conditions, and geographic origin ( Nogueira et al., 2012 ). Essentially, bee pollen has many benefits for human health. According to Li et al. (2018) , bee pollen

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