Verification of animal species in ham and salami by DNA microarray and Real time PCR methods

Consumer protection and detecting of adulteration is very important and has a wide societal impact in the economic sphere. Detection of animal species in meat products and the use of combining different methods is one of the means to achieve relevant product status. The aim of this study was to reveal whether or not the products label clearly meets the content declared by producer. In our study, 29 samples of meat products such as salami and ham obtained from stores and supermarkets in Slovakia were analyzed to detect the existing animal species according to the product label the use of Chipron LCD Array Analysis System, Meat 5.0. Products in which the presence of non-declared animal species has been detected were subjected to testing by the innuDETECT PCR Real-Time Kit, repeatedly. The results showed that 20 (68.96%) samples were improperly labeled. From in total 14 tested ham samples 11 (78.57%) products exhibited non-conformity with declared composition. Tested salami samples (15) revealed 9 (60%) incorrectly labelled products. The results obtained by DNA Microarray and Real Time PCR methods were identical, and both methods should be extensively promoted for the detection of animal species in the meat and meat products

Determining the presence of chicken and turkey meat in selected meat products using realtime PCR method

The one of the most convenient method for the identification of animal species in raw and processed meat products is the examination of DNA sequences. Real-Time PCR are particularly suitable because even small fragments of DNA formed during heat processing of the meat can be amplified and identified. TaqMan Real-Time PCR is a rapid, convenient and sensitive assay for meat identification. For chicken and turkey meat identification we were using species-specific primers and TaqMan probe designed on the mitochondrial cytochrome b. The intensity of the fluorescence signal has risen at a variety of different samples. We analysed sixteen the samples of turkey meat products and we found the incidence of chicken at nine samples in the range of the detection range of the reaction0.1 to 100%.  Sample 8 fluorescence intensity exceeded the detection threshold in the 22.11 cycle (Cp = 22.11); Sample 6, (Cp = 23.19); Sample 1 in 27.08 cycle (Cp = 27.08); Sample 7 in 31,7 cycle (Cp = 31.7) and sample 5 in 32.32 cycle (Cp = 32.32). All Cp values for these samples fluorescence intensity exceeded the detection threshold in earlier cycles as sample the 100% turkey DNA. It follows that in the samples no. 8, 6, 1, 5, and 7 is in the range of chicken DNA detection range of the reaction, from 0.1 to 100%. Sample 11 in the cycle 27,08 (Cp = 27.08); Sample 10 in the cycle 27.8 (Cp = 27.8); sample 16 in 28.03 cycle (Cp = 28.03) and sample 13 in the cycle of 29.18 (Cp = 29.18). In recognition of the results of the monitoring of the content of chicken meat in meat products it is appropriate to further verification and testing detection kits used to work for possible use in practice since it has been found to be sufficient sensitivity and specificity to 30 cycle reaction

The yield of dna in thermal terated deer meat

Residuals of DNA are one of the most important factors for detection, traceability and reverse authentication of deer meat. In this project we isolated DNA from deer processed meat and analysed by electrophoresis. Goal of the study was compute ratio between raw meat and several heat processed deer meat. Samples were prepared by five heat treatment techniques (pan roasted with temperature 180-240°C, fried with 156°C, braised with temperature 100-150°C, boiled in 100.2°C water and autoclaved in different time intervals). The highest amount of residual DNA 1927ng was obtained with two hours boiled sample. The lowest value 89.89ng was obtained with one hour braised sample. In technological adjustments highest amount of DNA and 1927ng, so the total yield of 192.7ng.-l was observed in the sample we cooked for two hours at boiling temperature.

Identification of differences in chemical composition among whole stick and sliced Nitran salamis trough principal component analysis

The subject of this work was to examine differences in chemical composition of sliced and whole stick Nitran salamis, purchased from various manufacturers. Nitran salamis are traditional dry fermented meat products of Slovak origin. Taking into account variations in raw materials, production process and potential adulteration, differences in chemical composition within one brand of salami from different manufacturers might be expected. Ten salamis were determined for basic chemical composition attributes and Principal Component Analysis was applied on data matrix to identify anomalous ones. It has been shown that six attributes, namely: protein without collagen of total protein, total protein, total meat, total fat, collagen of total protein and NaCl, were the most important for salamis as first two Principal Components together explained 70.16% of variance among them. Nitran D was found to be the most anomalous salami, as had the lowest value of protein without collagen of total protein (14.14% ±0.26%), total protein (17.42% ±0.44%), total meat (120.29% ±0.98%) and the highest one of total fat (50.85% ±0.95%), collagen of total protein (18.83% ±0.50%) and NaCl (9.55% ±1.93%), when compared to its whole stick variant Nitran C and other samples. In addition to collagen of total protein content, Nitran D together with Nitran A, F and H did not satisfied the legislatively determined criterion, which is ≤16%. This suggested that extra connective tissues were added to intermediate products, which resulted in high variability and inferior quality of final products. It is a common practice in the meat industry to increase the protein content or water binding properties of meat products

Characteristics of textural and sensory properties of Oštiepok cheese

Oštiepok is a traditional half-fat semi-hard cheese made in Slovakia. The basic raw material used to produce oštiepok cheese is ewe's milk, a mixture of ewe's and cow's milk or cow's milk. Oštiepok cheese is produced either directly at a small-scale mountainside sheep farm, using the traditional on-farm method of production, or at dairies, using the industrial method. Oštiepok cheese was produced as far back as the beginning of the 18th century. An industrial production of Oštiepok cheese using cow's milk were laid by the Galbavý family in Detva (Slovakia) in 1921. The cheese is originally made by cutting off fresh sweet cheese, which is pressed into a wooden, hand-cut and decorated round shape where it is left to stand. Subsequently, it is removed and immersed in warm salty water, left to stand there until the salt penetrates completely in. Then it is necessary that it pass slightly. In its salty water, the ostrich produces its traditional durability, its surface is slightly peeled, mostly yellowish. This cheese may or may not be steamed and may be smoked or unsmoked. Slovenský oštiepok is a protected trade name under the EU's protected geographical indication. A similar cheese is made in the Polish Tatra Mountains under the name Oscypek. The cheeses differ in ingredients' ratios, cheesemaking process and the characteristics of the final products. In this study we have characterized textural and sensory properties of the Oštiepok cheese produced in Slovakia made from ewe's milk, a mixture of ewe's and cow's milk and cow's milk

Optimalisation of species identification of common carp (Cyprinus carpio) using SYBR® green I real-time PCRmethod

European Union Member States, together with a number of countries around the world, places great emphasis on ensuring the protection of consumers as a potential food allergic from food allergies. to inform consumers that their product may contain any of the risk of allergenic ingredients. For species identification of fish and fish products as a potential food allergens are used by many analytical methods as well as their authentication. We are in our work applied the method of SYBR® Green I. Real-Time PCR. We focused on pre-designed molecular - genetic marker of common carp (Cyprinus carpio), which comes from the mtDNA control D - loop area. We analyzed its presence in DNA isolates from the 5 kinds of freshwater fish, diluted to 10 % concentration. Results of using the optimized SYBR ® Green I Real-Time PCR method for species identification common carp (Cyprinus carpio) indicate to its suitability

Detection of ovine milk adulteration using taqman real-time pcr assay

Food safety, quality and composition have become the subjects of increasing public concern. To prevent fraud and enhance quality assurance, credible analysis of dairy products is crucial. Bovine milk is more widely available and cheaper than milk of sheep and goat. Bovine milk is also processed in large quantities to produce a range of dairy produce. DNA-based methods have proven to be more reliable, because of the stability of DNA under the conditions of high temperature, high pressure, and chemical treatment used during the processing of some food products. The commercial InnuDETECT cheese assay based on the principle TaqMan real-time PCR systems have been tested for the identification and quantification of bovine DNA in ovine milk samples. DNA was extracted using the InnuPREP DNA Mini Kit and quantified by the QuantiFluor dsDNA system. The assay showed good linearity, with correlation coefficient of R2 = 0.983 and efficiency of 86%. The internal control amplified fragment from different mammalian species (cow, sheep and goat), with similar CT values. Detection of bovine DNA in milk mixtures was achieved even in samples containing 0.5% of bovine milk. The InnuDETECT cheese assay has been successfully used to measure bovine DNA in ovine milk, and will prove useful for bovine species identification and quantitative authentication of animal-derived products

The effect of UV-C irradiation on grape juice turbidity, sensoric properties and microbial count

In this work, we investigated the effect of UV-C radiation (254 nm) on turbidity, microbial count and sensoric properties of the grape juices treated or not treated with sulphur dioxide. The UV-C radiation is considered to be germicidal against microorganisms. This technology is routinely used to treat drinking water. Application of this method for the purpose of treating the wine was tested in few studies. These studies have shown a positive effect on the inactivation of microorganisms, but they not dealt in detail with the sensory properties of grape juice after the treatment. The main idea of using this method appears to eliminate the sulphur dioxide from wine making technology. There are people who have a genuine allergy to sulfites, and these allergies are often linked with asthma. These people have an rapid onset of symptoms when drinking liquids like wine treated with sulphur dioxide. In our work we have found that the application of this method of treating the grape juice is problematic. Intensity of UV-C radiation increases the turbidity of grape juices. This effect was observed in all grape juices with or without addition of sulphur dioxide and also in clarified or not clarified grape juices. We found that UV-C radiation negatively affect the sensory properties of grape juices. This effect was more pronounced in grape juices treated with SO2. The smell and taste were significantly negatively changed. Exposure of grape juice treated with sulphur dioxide to UV-C radiation can probably lead to arising the sulphur compounds, which affects the smell and taste of grape juices. Also, it is very likely that the negative change in taste and smell may affect the quality of produced wines. For this purpose, we do not recommend to use UV-C treatment for the grape juice treatment. It will be interesting to conduct a detailed analysis of the grape juices composition before and after UV-C radiation treatment

Effect of thermal treatment on rutin content in selected buckwheat products using calcium as an internal tracer

Reversed-phase high-performance liquid chromatography (RP-HPLC) was used for rutin (quercetin-3-rutinoside) determination in selected buckwheat products (whole meal flour, broken seeds, seed hulls, herbs and baked cereal breads). The effect of various thermal procedures on content of rutin was evaluated using calcium as an internal tracker to correct changes in mass and composition of the buckwheat products. These factors are very seldom taken into account. The results show non-significant changes in rutin levels obtained in whole meal flour and broken seed samples after thermal treatment up to 150°C. Higher temperature already caused sudden fall in the observed rutin concentrations. The evaporation of some volatile compounds and degradation products can decrease the mass of the samples and formally increase the content of rutin (35.5 ±4.7 mg per 100 g for whole meal flour and 10.2 ±0.4 mg per100 g for broken seeds at 150°C). Serious decrease of rutin contents at elevated temperatures ( > 150°C) can be explained by its degradation (by breaking off the C-C bond in quercetin-3-rutinoside moiety) and/or evaporation (24.3 ±1.4 mg per 100 g for whole meal flour and 3.06 ±0.3 mg per100 g for broken seeds at 180°C). In case of baked cereal breads the level of rutin changed in dependence on the ratio between buckwheat and corn flour. Longer time leaching and higher temperature implicate higher rutin content in infusions prepared from buckwheat seed hulls and herbs. © 2017 Potravinarstvo Slovak Journal of Food Sciences, License

Effect of thermal treatment on rutin content in selected buckwheat products using calcium as an internal tracer

Reversed-phase high-performance liquid chromatography (RP-HPLC) was used for rutin (quercetin-3-rutinoside) determination in selected buckwheat products (whole meal flour, broken seeds, seed hulls, herbs and baked cereal breads). The effect of various thermal procedures on content of rutin was evaluated using calcium as an internal tracker to correct changes in mass and composition of the buckwheat products. These factors are very seldom taken into account. The results show non-significant changes in rutin levels obtained in whole meal flour and broken seed samples after thermal treatment up to 150°C. Higher temperature already caused sudden fall in the observed rutin concentrations. The evaporation of some volatile compounds and degradation products can decrease the mass of the samples and formally increase the content of rutin (35.5 ±4.7 mg per 100 g for whole meal flour and 10.2 ±0.4 mg per100 g for broken seeds at 150°C). Serious decrease of rutin contents at elevated temperatures (>150°C) can be explained by its degradation (by breaking off the C-C bond in quercetin-3-rutinoside moiety) and/or evaporation (24.3 ±1.4 mg per 100 g for whole meal flour and 3.06 ±0.3 mg per100 g for broken seeds at 180°C). In case of baked cereal breads the level of rutin changed in dependence on the ratio between buckwheat and corn flour. Longer time leaching and higher temperature implicate higher rutin content in infusions prepared from buckwheat seed hulls and herbs