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

Analysis of consumer behavior at chocolate purchase

At food purchase consumer is affected by several factors. In this work analysis of consumer behavior at chocolate purchase was performed involving 277 respondents. Statistical testing of results was performed by Chi - Square statistic, correlations have been tested with use of the Cramer's coefficient. It was found, that 86% of respondents consume chocolate. Factors affecting respondents at purchase were recommendations of friends, acquaintances (32%), brand of chocolate (24%), price (16%), personal experience (12%), health restrictions and allergies (11%). Less important factors when choosing chocolates are flavor (4%), nutritional quality (3%), country of origin (2%) and chocolate packaging (1%). In the consumption of chocolate moderate correlation among various categories of economic activity of respondents was confirmed. Chocolate was consumed mainly by respondents whose monthly income ranges from 801 to 1001 €. We found that consumers prefer milk chocolate followed by dark and white at the end. In terms of gender the most commonly was chocolate consumed by women, once to three times a week. The same frequency of chocolate consumption dominates at the categories of students and employee. Expenses frequently spent to buy chocolates were from 1-3 € per week by young people (18-23 years) and middle age generation of people (46-55 years)

Antioxidant effects of herbal extracts and their food application

Herbal extracts are considered as a good sources of antioxidant compounds. This work describes antioxidant effect of 15 kinds of herbs. Three different antioxidant assays were used, Trolox equivalent antiradical activity (TEAC), test based on deoxyribose oxidation and DPPH method. The TEAC values ranged from 0.38mM to 0.77 mM. Deoxyribose assay showed antioxidant activity of selected extracts expressed as the inhibition of formation of oxidative products of deoxyribose from 2.68 to 50.05 %.  The DPPH method values ranged from 6.47 to 73.80 %. Extracts of Prunus spinosa L., Euphrasia rostkoviana Hayne were the best antioxidants confirmed by all methods. Scrophularia nodosa L. extract showed the weak antioxidant effect  determined by all selected methods. Phenolic content was in relation to the antioxidant effect of herbs, very high significancy between DPPH and polyphenols content was found. To improve selected properties of apple juice (taste, smell, functional properties) by addition of medicinal herbs was achieved in this work. Antioxidant effect  of  apple juice variants with herbs additions determined by DPPH method was high and ranged from 73 to 78.49 %. Herbal extracts can be utilised in selected combinations to improve sensory and functional properties of some kinds of beverages

Winter squash (Cucurbita moschata Duch) fruit as a source of biologically active components after its thermal treatment

To one of the most valuable pumpkin fruit belongs winter squash (Cucurbita moschata Duch). The aim of this work was to assess the quality of C. moschata fruit and to assess the dynamics of compositional changes after the heat treatment of the pulp. We used six varieties Liscia, Orange, Hannah, UG 201 F1, Waltham, Serpentine. In the samples were analyzed carbohydrate content (glucose, fructose and sucrose), total polyphenols, total carotenoids and antioxidant activity. The fresh pulp and pulp after the heat treatment were observed. Content of carbohydrates was determined by FTIR infrared spectroscopy. Content of total carotenoids, polyphenols and antioxidant activity was determined by spectrophotometry. As the dominant sugar was found to be sucrose. The lowest content of all carbohydrates was found in the variety Serpentine. Fructose content ranged from 7.59 to 12.32 g.100 g-1 dry matter, glucose content from 7.23 to 9.79 g.100 g-1 dry matter and sucrose content 38.67 to 55.94 g.100 g-1 dry matter. After processing there was found a decrease in the sucrose and the slight increase in glucose and fructose content. Total carotenoid content in fruits ranged from 39.01 to 97.67 g mg.100 g-1 dry matter, the content of total polyphenols from 443.98 to 565.44 mg GAE.100 g-1 dry matter and antioxidant activity from 680.18 to 851.87 mg AA.100 g-1 dry matter. After the heat treatment, there was found some decrease in total carotenoids, polyphenols and antioxidant activity as well

Selected parameters of quality and safety of herbal tea

The aim of this work was to assess the heavy metal presence and possible microbiological contamination in herbal teas. Evaluation of selected tea products was performed from Nitra locality during years 2009 - 2013. Microscopic filamentous fungi detection, bacteria such as Escherichia coli and Salmonella spp. were compared to requirements given in the Codex Alimentarius of Slovakia. The highest permissible limit for microscopic filamentous fungi was not exceeded (in 32 observed herbal tea samples). For incidence of Escherichia coli, 93 samples were investigated and for Salmonella spp., 91 herbal tea samples. No sample showed the presence of Salmonella spp., and at E. coli maximum permitted presence was detected below limit. Among chemical parameters, cadmium, lead and mercury content were monitored. The highest amount of lead and mercury was found in year 2012. In 2009, the highest cadmium content was found. The average content of lead in all 100 inspected herbal tea samples was 0.784 mg.kg-1 so all the samples met requirements defined in the legislation. The mean content of mercury (98 investigated herbal tea samples) was 0.0161 mg.kg-1 so all samples met the requirements as well. Average cadmium content was 0.1702 mg.kg-1 while the highest permitted limit for cadmium is 1.0 mg.kg-1. All herbal tea samples were in accordance with the legislation except one (white willow bark tea) with a very high content of cadmium (4.36 mg.kg-1)

The prevalence of Salmonella infections in laying hen flocks producing eggs and their impact on the public health

Since 2008, Slovakia has implemented the National control program of Salmonella infections in laying hen flocks. This program requires the farm operators to monitor and investigate the invasive types of Salmonella (S. Enteritidis and S. Typhimurium) according to STN ISO 6579. The aim of this study was to perform a microbiological examination of dust and chicken droppings samples of laying hens in the Trenčín region for the presence of Salmonella by Horizontal method according to STN ISO 6579: 2002, to compare results with the statistics across Slovakia and selected EU countries and to evaluate the impact of official controls of salmonellosis in animals and humans.  In the years 2009 - 2013 in the Trenčín region, 730 samples of dust from the conveyor belts and droppings of laying hens were taken to determine the prevalence of Salmonella in individual rearings. In these years, the incidence of positive samples was found from 0% to 29.17%. For the period from 2009 till 2013 was reported 22833 salmonellosis cases in human population of Slovakia, while in the Trenčín region it was 2636. Five-year EU-trend (2009 - 2013) showed a statistically significant decrease of salmonellosis occurence (with a mean reduction of 12% per year). The Wilcoxon signed-rank test was performed in order to provide in-depth epidemiological assessment of salmonellosis cases in Trenčin region in relation to selected characters: etiological agens, transmission mechanism, age, location as well as seasonality of infection

Research And Practice: Quantification Of Raw And Heat-Treated Cow Milk in Sheep Milk, Cheese And Bryndza By ELISA Method

The aim of this study was to test the reliability of commercial ELISA tests (RC-bovino) within raw and heat treated cow milk detection in sheep milk and cheese in order to obtain a high-quality, reliable and economically beneficial method suitable for routine application in practice. These tests were subsequently used for quantification of cow milk in commercial "Bryndza". Raw sheep milk, cow milk and heat-treated cow milk (pasteurisation at 72 °C for 15 sec or at 85 °C for 3 sec) were mixed in precisely defined proportions (0 - 100% cow milk in sheep milk). The milk mixtures were sampled to detect adulteration and subsequently cheese was made. By ELISA tests was possible to determine these amounts of raw cow milk in sheep milk: 0.5% (0.2%), 5 % (4.81%), 50% (42.08%) and 75% (56.52%). The pasteurized samples in different combinations gave lower optical density responses than those prepared from raw milk (by approximately 60%). In context with the above mentioned, the relationship between the real and detected amount of cow milk (%) in different production stages (milk, cheese) using a regression analysis was examined. However, a lower reliability of the detection was indicated by R2 values, which ranged from 0.4058 (cheese) to 0.5175 (milk). In practice this means that although individual percentage (%) of cow milk in the sample can be detected, but in the unknown sample it can not be clearly confirm whether the cow milk was raw or heat-treated. In this context, the results can be inaccurate and may not correspond to the real situation. Within monitoring phase of this research, 9 samples of bryndza were analysed with the results of detected cow milk ranged from 11.56% to 14.3%. The obtained results confirm that the appropriate selection of ELISA tests can become an important factor in the setting of analytical capabilities for the detection of milk and cheese adulteration

Vplyv prídavku prírodných extraktov na kvalitu a trvanlivosť bezgluténových pekárskych výrobkov

The work deals with the application of natural functional ingredients as possible substitute for synthetic additives in gluten-free baguettes with potential extension of their shelf life. It is focused on the use of natural extracts such as rosemary (1% addition) and grape seeds (1-2% addition), while the baguettes were packed in the modified atmosphere in order to prolong their shelf life. They were tested after baking and after one week of storage (in the plastic bag and in the modified atmosphere package) for texturometric and sensory properties, water activity and pH. Natural extracts showed highly significant (P≤0.01) positive effect on the texture of the products. In all samples, the firmness of the baguettes decreased compared to the control sample, and the modified atmosphere softened the products compared to the plastic bag (P≤0.01). In the package with the modified atmosphere, we observed the decrease in the pH of the products, which can be evaluated positively. At the sensory evaluation, the sample with the addition of rosemary extract achieved the best results, compared to the control sample as statistically significant (P≤0.01).Práca sa zaoberá aplikáciou prírodných funkčných ingrediencií (extraktov) ako možnej náhrady syntetických prídavných látok v bezlepkových bagetách s potenciálnym predĺžením ich trvanlivosti. Je zameraná na použitie prírodných extraktov ako sú rozmarín (prídavok 1%) a hroznové semená (prídavok 1-2%), pričom bagety boli balené v modifikovanej atmosfére, aby sa predĺžila ich trvanlivosť. Po upečení a po jednom týždni skladovania (v plastovom vrecku a v obale v modifikovanej atmosfére) boli testované na texturometrické a senzorické vlastnosti, aktivitu vody a pH. Prírodné extrakty vykazovali vysoko významný (P≤0,01) pozitívny vplyv na textúru produktov. Vo všetkých vzorkách sa tuhosť bagiet v porovnaní s kontrolnou vzorkou znížila a modifikovaná atmosféra zmäkčila výrobky v porovnaní s plastovým vreckom (P≤0,01). V obale s upravenou atmosférou sme zaznamenali pokles pH produktov, čo možno hodnotiť pozitívne. Pri senzorickom hodnotení dosiahla najlepšie výsledky štatisticky významné (P≤0,01) vzorka s prídavkom rozmarínového extraktu v porovnaní s kontrolnou vzorkou

Chemical Composition of White Wines Produced from Different Grape Varieties and Wine Regions in Slovakia

In this work, chemical parameters such as sugar (glucose and fructose) content, organic acid (total acids, malic and tartaric acids), total phenolic content and the antioxidant activity of 12 white wines (chardonnay, pinot blanc and pinot gris) from various wine regions in Slovakia were studied in order to identify differences among the varieties and wine-growing regions. The wine samples were examined by Fourier-transform infrared spectroscopy (FTIR) and UV-VIS spectrophotometry (for determination of total polyphenolic content (TPC) and total antioxidant activity (TAA)) methods. Content of alcohol ranged between 11.50% and 13.80% with the mean value 12.52%. Mean content of total acids varied between 4.63 ± 0.09 and 6.63 ± 0.05 g.L−1, tartaric acid varied between 1.62 ± 0.09 and 2.93 ± 0.03 g L−1, malic acid was found in the concentrations ranged from 0.07 ± 0.05 and 2.50 ± 0.08 g L−1 and lactic acid was present between 1.53 and 0.01 g L−1. The content of fructose was, in general, higher in the samples from the Južnoslovenská and Nitrianska wine regions and glucose was higher in the Malokarpatská wine region. Chardonnay wines showed the highest content of total polyphenols and the antioxidant activity in the samples ranged from 51.06 ± 027 to 72.53 ± 0.35% inhibition of DPPH. The PCA analysis based on chemical descriptors distinguished the Nitrianska and Stredoslovenská wine regions. According to similarities among the wine samples, four main classes were formed by cluster analysis