Health safety aspects of foodstuffs intented for phenylketonurics

Phenylketonuria is a rare metabolic disorder that occurs due to the lack of liver enzyme phenylalanine hydroxylase. Untreated it leads to mental retardation, delayed development of speech, microcephaly, epilepsy, behavioral problems etc. Its treatment consists of strict diet, very low in phenylalanine content. The aim of this study was to determine the health safety and suitability of 17 selected foods labeled as „low in protein" respectively „foods low in phenylalanine". Analyses were focused on their phenylalanine content and aminoacid representation. The other aim was to compare phenylalanine measured with the content declared by the producers on their label. By product origin, the largest amount of foodstuffs originated from Poland (59%), followed by Germany (23%) and equal representation (6%) had Slovakia, Hungary and Sweden. Automatic analyzer AAA 400, using ion exchange chromatography, analyzed the samples. The lowest determined phenylalanine content was 1 mg.100g-1 (in rubber candy) and the highest 299 mg.100g-1 (in paté). Powdered egg alternative was monitored as the second highest source of phenylalanine. Phenylalanine content in the monitored foods ranged from 1 to 299.6 mg. 100 g-1 respectively, and increased in the following order: Gum candies (1 mg.100g-1) < Cherry jelly (1.4 mg. 100g-1) < Flour (5.8 mg.100g-1) < Flour (5.9 mg.100g-1) < Spaghetti (8.7 mg.100g-1) < Pasta (9.9 mg.100g-1) < Waffle (14.2 mg.100g-1) < Salty sticks (23.8 mg.100g-1) < Chocolate (24.1 mg.100g-1) < Bread (26 mg.100g-1) < Breadcrumbs (27.1 mg.100g-1) < Sticks with salt (30.3 mg.100g-1) < Ice Cornets (30.8 mg.100g-1) < Walnut cookie (37.2 mg.100g-1) < Instant soup with noodles (46.1 mg.100g-1) < Powdered egg alternative (58 mg.100g-1) < Pate (299.6 mg.100g-1). Only seven products of 17 observed showed low phenylalanine content, less than 20 mg.100g-1

Proteolysis During Manufacture And Ripening/Storing Of "Olomoucke Tvaruzky" Cheese (Pgi)

Twenty-two free amino acid (FAA) concentrations were observed during manufacture (1st, 3rd and 7th days of production) and ripening period (42 days storing at 8 degrees C) of "Olomoucke tvaruzky" (PGI, smear acid cheese). Sensory attributes were also analysed during ripening period. The free amino acids were determined by means of ion-exchange chromatography. The development of the individual FAA content positively correlated with the ripening period (r = 0.7734-0.9229; P < 0.01). The results gave information about the development precursors (FAA) of typically sensory active compound in "Olomoucke tvaruzky" (PGI) during its production and especially ripening. In conclusion, we found that free amino acid concentration as finally products of proteolysis are positive with improved flavour.National Agency for Agriculture Research [QJ1210300]; Internal Grant project of Tomas Bata University in Zlin [IGA/FT/2012/026

The viscosity of processed cheese sauces depending on addition type and concentration of 1-monoglycerides

The aim of this work was to study viscosity of processed cheese sauces with 1-monoglycerides (MAG) addition. Six types of 1-monoglycerides (1-monocaprin, C10:0; 1-monolaurin, C12:0; 1-monomyristin, C14:0; 1-monopalmitin, C16:0; 1-monostearin, C18:0; 1-monoolein, C18:1) in concentration of 0.25 and 0.50% w/w were used. Control samples were prepared without MAG but with lecithin. The lowest values of viscosity were found in control samples. The viscosity increased with extending of chain fatty acid in the molecule of monoglycerides. The highest viscosity was found in samples with 1-monomyristin

Graphics and Presentation in the TeX and LaTeX Systems

Bakalářská práce se zabývá způsobem začlenění externích grafických souborů do dokumentů LaTeXu a vytvářením grafiky interními prostředky TeXu. Popisuje základní vlastnosti nástavbového balíčku PSTricks a jeho rozšíření pro tvorbu 2D a 3D grafů, speciálních matematických funkcí a elektrických obvodů. Další oblastí, kterou se práce zabývá, je způsob vytváření PDF prezentací pomocí třídy Beamer. V rámci této práce byla navržena struktura zdrojového SVG souboru, který zobrazuje elektrické obvody nebo vývojové diagramy. Byla vytvořena příslušná konverzní šablona XSLT, která zajišťuje převod těchto schémat z formátu SVG do formátu PSTricks a~umožňuje tyto grafické soubory využít v systému LaTeX.This bachelor’s thesis deals with the insertion of external graphic files into LaTeX documents and the creation of graphics using internal tools of TeX. It describes the basic properties of the PSTricks additional package and its expansion enabling the creation of 2D and 3D graphs, special mathematical functions and electrical circuits. The work deals also with the method of creating PDF presentations using the Beamer class. This work suggests a structure of a source SVG file displaying electric circuits or flow charts. It also involves the creation of an XSLT conversion template providing for the conversion of these charts from the SVG format to the PSTricks format making it possible to use these graphic files in the LaTeX system.

Factors affected decarboxylation activity of Enterococcus faecium isolated from rabbit

  Biogenic amines (BA) are basic nitrogenous compounds formed mainly by decarboxylation of amino acids. There are generated in course of microbial, vegetable and animal metabolisms. The aim of the study was to monitor factors affected production of biogenic amines by Enterococcus faecium, which is found in rabbit meat. Biogenic amines were analyzed by means of UPLC (ultrahigh performance liquid chromatography) equipped with a UV/VIS DAD detector. Decarboxylation activity of E. faecium was mainly influenced by the cultivation temperature and the amount of NaCl in this study. E. faecium produced most of the monitored biogenic amines levels: tyramine ˂2500 mg.l-1; putrescine ˂30 mg.l-1; spermidine ˂10 mg.l-1 and cadaverine ˂5 mg.l-1

The effect of individual phosphate emulsifying salts and their selected binary mixtures on hardness of processed cheese spreads

The aim of this work was to observe the effects of emulsifying salts composed of trisodium citrate and sodium phosphates with different chain length (disodium phosphate (DSP), tetrasodium diphosphate (TSPP), pentasodium triphosphate (PSTP) and sodium salts of polyphosphates with 5 different mean length (n ≈ 5, 9, 13, 20, 28)) on hardness of processed cheese spreads. Hardness of processed cheese spreads with selected binary mixtures of the above mentioned salts were also studied. Measurements were performed after 2, 9 and 30 days of storage at 6 °C. Hardness of processed cheese increased with increase in chain length of individually used phosphates.  Majority of applied binary mixtures of emulsifying salts had not significant influence on hardness charges in processed cheese spreads. On the other hand, a combination of phosphates salts (DSP with TSPP) was found, which had specific effect on hardness of processed cheese spreads. Textural properties of samples with trisodium citrate were similar compared to samples with DSP

Quality changes of long-life foods during three-month storage at different temperatures

The aim of this study was to describe quality changes of eight long-life foods (instant potato purée with milk, instant goulash soup, canned white-type cheese, pre-baked baguette, szeged goulash meal-ready-to-eat, canned chicken meat, pork pate and canned tuna fish) during three-month storage at 4 different temperatures (-18 °C, 5 °C, 23 °C and 40 °C). These temperatures were chosen to simulate various climatic conditions in which these foods could be used to ensure the boarding during crisis situations and military operations to provide high level of sustainability. Foods were assessed in terms of microbiological (total number of aerobic and/or facultative anaerobic mesophilic microorganisms, number of aerobic and anaerobic spore-forming microorganisms, number of enterobacteria, number of yeasts and/or moulds), chemical (pH-values, dry matter, fat, crude protein, ammonia and thiobarbituric acid reactive substances contents), texture profile (hardness) and sensory (appearance, consistency, firmness, flavour and off-flavour) analyses. Microbiological analyses showed expected results with the exception of szeged goulash, pork pate and tuna fish, which, although being sterilised products, contained some counts of bacteria. The decrease of pH-values and increase of dry matter, ammonia and thiobarbituric acid reactive substances contents were observed during the storage of all foods due to prolonged storage time and/or elevated storage temperature. Furthermore, according to texture profile analysis, hardness of cheese and baguette rose as a result of both storage temperature and time. Finally, the highest storage temperature (40 °C) resulted in a deterioration of sensory quality (especially flavour) of most foods; the exceptions were pate and tuna fish which retained good sensory quality throughout 3-month storage at all temperatures. © 2017 Potravinarstvo Slovak Journal of Food Sciences

Antioxidant properties of processed cheese spread after freeze-dried and oven-dried grape skin powder addition

Processed cheese spread (PCS) is a popular product with high nutritional value and containing protein, fat and minerals. Grape skin is waste from winery processing plants that still has phenolic substances with significant antioxidant activity that could be used for valorisation of processed cheese and increasing the content of nutrients, phenolics and overall antioxidant properties. Both oven-dried (OD) and freeze-dried (FD) grape skin (GS) powder was characterised by the principal ingredients, the content of phenolic compounds and antioxidant capacity. Similarly, the influence of the addition of OD-GS and FD-GS powders on processed cheese spread (PCS) at 1% and 2% (w/w) levels were examined. The OD-GS and FD-GS powders were characterised by protein content, fat content, moisture and dietary fibre, thus showing that drying technique did not affect those parameters. The OD-GS powder exhibited higher content of rutin, (+)-catechin, (-)- epicatechin and total flavonoid content (TFC), while higher total phenolic content (TPC) and ABTS radical cation were observed for freeze-dried GS powder. Fortification of PCS with 1% and 2% (w/w) of GS powder increased protein content. An ANOVA procedure revealed that addition of FD-GS powder to processed cheese spread was superior to TPC values together with rutin, (+)-catechin, and (-)-epicatechin contents. The higher phenolic contents reflected the higher antioxidant capacity of PCS samples fortified with FD-GS powder. Freeze-dried grape skin powder was the better choice for valorisation of processed cheese spread. © 2020 Potravinarstvo Slovak Journal of Food Sciences, Licence

Distribution of constrained maximum coordinates

The aim of this article was to find the distribution of the random vector that determines constrained maximum coordinates of a regression function. At first the used regression function is described and the asymptotic distribution of the unconstrained maximum is derived. Then the distribution of constrained maximum coordinates is suggested for data from the food industry regarding the influence of emulsifying salts on the hardness of processed cheese

The effect of sterilization on size and shape of fat globules in model processed cheese samples

Model cheese samples from 4 independent productions were heat sterilized (117 °C, 20 minutes) after the melting process and packing with an aim to prolong their durability. The objective of the study was to assess changes in the size and shape of fat globules due to heat sterilization by using image analysis methods. The study included a selection of suitable methods of preparation mounts, taking microphotographs and making overlays for automatic processing of photographs by image analyser, ascertaining parameters to determine the size and shape of fat globules and statistical analysis of results obtained. The results of the experiment suggest that changes in shape of fat globules due to heat sterilization are not unequivocal. We found that the size of fat globules was significantly increased (p &lt; 0.01) due to heat sterilization (117°C, 20 min), and the shares of small fat globules (up to 500 ÎĽm2, or 100 ÎĽm2) in the samples of heat sterilized processed cheese were decreased. The results imply that the image analysis method is very useful when assessing the effect of technological process on the quality of processed cheese quality