Wyniki wyszukiwania - BazTech

1

The rapid acoustic screening of deoxynivalenol (DON) in grain

Juodeikiene G., Vidmantiene D., Basinskiene L., Bartkiene E., Koe W. J.

Ekologia i Technika

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2005

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R. 13, nr 5

187-192

EN

Mycoxins in food and feed are considered as important safety issues of growing concern. Most scientific developments have occurred in the last decades in the area of mycotoxins. Formal health risk assessments have been carried out or are underway by the Joint FAO/WHO Expert Committee on Food Additives (JECFA). One of the from an economic point of view and less from a health point of view important mycotoxin is deoxynivalenol (DON) or vomitoxin. DON is a toxin formed by fungi of the genus Fusarium and occurs mainly on grains and corn. In Europe alone, Fusarium head blight destroys a fifth of the wheat harvest. Limits and regulations for mycotoxins in food and feed have been established in many countries and recently the EU published legislation in this field. An array of (formally validated) analytical methods and (certified) reference materials has become available. Quantitative methods of analysis for regulatory purposes for mycotoxins often make use of immuno affinity cleanup with LC or GC separation techniques in combination with various types of detectors, including MS. There exist interesting newer developments in mycotoxin methodology, of which the application would need to be further explored, tested for performance and compared with the existing conventional methods. These methods include the powerful LC MS (MS) and GC MS bench top techniques, capillary zone electrophoresis, cell tests and others and for screening purposes (bio) sensor based techniques and non-invasive methods based on infrared and acoustic techniques. The promising acoustic technique is fast, effective, simple and reliable and is capable to be used in- and on-line. Further development and validation and calibration of this method in compare with existing state of the art conventional methods are necessary to make progress with this promising technology.

2

Microbial population in lithuanian spontaneous rye sourdoughs

Digaitiene A., Hansen A., Juodeikiene G., Josephsen J.

Ekologia i Technika

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2005

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R. 13, nr 5

193-198

EN

In order to study the composition of the lactic acid bacteria (LAB) population of spontaneous rye sourdoughs used for the manufacture of traditional Lithuanian bread, 56 strains of LAB were isolated from nine samples and identified. Morphological and phenotypic analysis showed the presence of six groups: four within lactic acid bacteria rods (43 % strains) and two within cocci (57 %). Genetic diversity was evaluated by using PCR amplification of 16S rDNA sequencing and ITS-PCR methods. Overall, 39 % were identified as P. pentosaceus, 18 % as P. acidilactici and L. farciminis, 16 % as Lactobacillus ssp., 7 % as L. curvatus and 2 % as L. sakei. Both the diversity and structure of the lactic microflora for sourdoughs varied among samples.

3

Comparison of enterodiol and enterolactone production from different plant products: cereals, berries and vegetables

Basinskiene L., Juodeikiene G., Bartkiene E., Ramonaitytel D., Liukkonen K.

Ekologia i Technika

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2005

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R. 13, nr 5

199-204

EN

The objective of this study was to determine the production of mammalian lignans such as enterolactone and enterodiol from ten cereal products (bran and flour), ten berries and ten vegetables by using the technique of in vitro fermentation with human fecal microbiota and to compare with the production of these lignans from flaxseed. Results showed a wide range (78.3 to 321.9 nmol/g) in the amount of mammalian lignans produces from cereal. Cereal brans were the highest producers of mammalian lignans (294.1 to 321.9 nmol/g). The lignan production from bran was 2.2 to 2.3 times higher than that from whole flour of the same kind of cereals. From berries the production of mammalian lignans ranged from 7.8 to 382.8 nmol/g depending on the product type. Cloudberries, raspberries and strawberries produced the higher amounts of mammalian lignans. The vegetables as compared to cereals and berriers produced the lower concentration of mammalian lignans (10.5 to 91.2 nmol/g) and potatoes among them were the higher producer. The study showed that cereal bran, especially rye bran, also some kind of berries (raspberries, strawberries, and cloudberries) could be an important source of these bioactive compounds. The data should be useful in the estimation of mammalian lignan production from a given diet and in the formulation of high lignan producing diet for the purpose of reducing the cancer risk.

4

Application of dynamic headspace technique and gas chromatography mass spectrometry methods for bread

Venskaityte A., Juodeikiene G., Hansen L., Petersen M.A.

Ekologia i Technika

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2005

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R. 13, nr 5

182-186

EN

Dynamic Headspace and Gas Chromatography and Mass Spectrometry (GC and MS) methods have been adapted for rye bread flavour analysis, optimising parameters: the amount of sample, trapping time, cold trap temperature and sample preparation method. Commercial rye bread was used as a reference. Experiments indicated that 25 g of sample could be taken for the test. Due to insufficient isolation of volatiles and flavour compounds in a short time period a prolonged trapping time of 40 min was chosen for the trapping the volatiles in the tube. Higher relative concentrations were obtained applying +5 C cold trap temperature in the GC device and using sample preparation method without water (dry sample preparation method). These parameters were successfully applied for rye bread flavour investigations.