Influence of starter culture to sensory quality of edam cheese during ripening

In the study were evaluated the Edam cheeses with fat content 30% and 45% w/w produced by two dairies (A, B) using two different starter cultures YY and LL during five months ripening. The effect of ripening was related to the texture of Edam, so as to determine the optimum ripening time. The ripening time had significant effect on sensory characteristics of the Edam cheese. The first three months were ripening cheese with 30% fat in dry matter evaluated much like cheese with 45% fat in dry matter, but in the following months of aging is already evident that with the starter culture LL cheeses were evaluated as taste pleasant. Both starter cultures produced an increase in the bitter taste of the cheeses after 3 months of ripening. However, cheeses with YY starter culture gradually lost bitterness during ripening, while for cheeses with LL starter culture the intensity of the bitter taste increased during ripening. These results were statistically significant. Increasing bitter taste formation excludes the possibility of using YY starter culture to make Edam cheese with a maturation period of more than 3 months.operational Program called Research and Development for Innovations - European Fund for Regional Development (ERDF)European Union (EU); state budget of the Czech Republic within the Centre of Polymer Systems Project [CZ.1.05/2.1.00/03.0111]; 2112 - Institutional Support for the Development of Research Organization

Storage of extra virgin olive oil and its impact on fatty acid levels

Peroxide value, acid value, and fatty acid content were monitored during two-year storage in the following products: Luccese Olio extra vergine d'oliva (LOEVDO), Blanqueta extra-virgin olive oil (BEVOO) and Agrocreta extra-virgin olive oil (AEVOO). In LOEVDO and BEVOO, peroxide value increased by 50%; AEVOO showed 80% growth. Maximum acid value was found solely in LOEVDO (<0.8%). All the analyzed samples contained almost identical proportions of fatty acids. Minute amount of lauric acid (C 12:0) was indentified in BVEOO samples only. The two-year storage resulted in growth of oleic and stearic acid levels and in decrease of linoleic and palmitic acids concentration. The percentage of SAFA, MUFA and PUFA complied with recommended levels.operational Program Research and Development for Innovations (Vyzkum a vyvoj pro inovace); European Fund for Regional Development (ERDF); state budget of the Czech Republic within the Centre of Polymer Systems Project [CZ.1.05/2.1.00/03.0111]; 2112 Institutional Support for the Development of Research Organizations (Institucionalni podpora na rozvoj vyzkumne organizace) - Brno University of Technology; MSMT C

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

Tin compounds in food-their distribution and determination

The aim of this work was optimization of the methods of trace-and ultratrace analysis, such as ICP-OES, ETA-AAS for charting the resources of individual forms of tin in foodstuffs. Increase of the sensitivity of the method of ICP-OES was achieved using the techniques of generation of hydrides, which was also optimized. Based on the information available on the occurrence of the different forms of tin, it appears that many of these organometallic compounds are contained in marine animals; attention has mainly focused on organisms such as marine fish, crustaceans, molluscs and algae. Tin compounds of predominantly inorganic origin can be found in foods and beverages which are packed in cans with a protective tin coating, too. The above mentioned methods have been applied to the analysis of selected beverages with low content of tin such as Coca Cola, Sprite, Fanta, Gambrinus 10°, PowerKing, and milk in the cans. Furthermore samples of animal origin as Sardines in oil, and Hunter's salami were examined, too. Prior to the determination of tin, samples need to be appropriately modified or analysed. Decomposition of the samples was done in the microwave system. Low pressure ion exchange chromatography with on-line detection of ICP-OES was used for separation of inorganic tin compounds. Separation of organically bound tin compounds was performed by HPLC on a column of ACE C-18, 3 µm, 15 cm x 1.0 mm with off-line detection by ETA-AAS. All of the above forms of tin compounds can be separated with this column. Due to the improvement in the detection of organically bounded tin, HPLC with identical ACE C-18 column coupled online for example with ICP-MS or spectrofluorimetry could be recommended. © 2019 Muhammad Arba et al

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&deg;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 &plusmn;4.7 mg per 100 g for whole meal flour and 10.2 &plusmn;0.4 mg per100 g for broken seeds at 150&deg;C). Serious decrease of rutin contents at elevated temperatures (&gt;150&deg;C) can be explained by its degradation (by breaking off the C-C bond in quercetin-3-rutinoside moiety) and/or evaporation (24.3 &plusmn;1.4 mg per 100 g for whole meal flour and 3.06 &plusmn;0.3 mg per100 g for broken seeds at 180&deg;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

Evaluation of selected physicochemical parameters of extra virgin olive oil commercialized in the Czech market and stored during a period of 5 months

The scope of this work was to evaluate the development of selected physicochemical parameters (free acidity, peroxide value and specific extinction coefficients in ultraviolet) of extra virgin olive oil, commercialized in the Czech market and stored for a time period of 5 months (at 20 ±5 °C). The tested extra virgin olive oil samples were stored under conditions simulating domestic and commercial storage environment, in which the impact of light and headspace volume were also examined. Moreover, all the analyzed samples fell within the established "extra virgin olive oil category", thus proving their legitimacy, authentication and excellent quality. Furthermore, all the monitored physicochemical parameters were affected by the progress of the storage period, the rising volume of headspace (due to more available oxygen in the container) and exposition to light, resulting in decreasing quality of the examined extra virgin olive oil samples. In addition, the storage of extra virgin olive oil samples in dark containers reported sufficient resistance to oxidation processes up to a period of 3 months, however, after this period signs of oil quality deterioration were reported. Nevertheless, if exposition to light occurred, accelerated decrease in the quality of the extra virgin olive oil samples was observed. © 2017 Potravinarstvo Slovak Journal of Food Sciences, License

Changes in phenolic content in ground red pepper (capsicum annuum l.) during storage

Dynamics of changes in phenolic content in ground red pepper spice (Capsicum annuum L.) was monitored during the period of 10/2016-01/2018. Phenolic compounds were determined: gallic acid, catechine, vanillic acid, caffeic acid, coumaric acid, ferulic acid, rutin, resveratrol, cinnamic acid. In order to carry out a relevant statistical evaluation, individual measurements were interpolated to obtain a weekly time series. The fastest weekly reduction in content occurs for cinnamic acid (0.9%), coumaric acid (0.6%), resveratrol (0.54%), catechine (0.53%), quercetin (0.47%), vanillic acid (0.47%), ferulic acid (0.39%), gallic acid (0.34%), and rutin (0.29%). For the total content of phenolic substances, weekly decrease of 0.4% was statistically significant (at significance level of 0.001). The losses of phenolic substances during storage are possible to be minimized partially by keeping in cold, dry, and dark storage areas, in airtight containers for wholesale and retail packages.European Fund for Regional Development ERDFEuropean Union (EU); state budget of the Czech Republic within the Centre of Polymer Systems Project [1.05/2.1.00/03.0111]; 2112-Institutional Support for the Development of Research Organization

Evaluation of selected physicochemical parameters of extra virgin olive oil commercialized in the Czech market and stored during a period of 5 months

The scope of this work was to evaluate the development of selected physicochemical parameters (free acidity, peroxide value and specific extinction coefficients in ultraviolet) of extra virgin olive oil, commercialized in the Czech market and stored for a time period of 5 months (at 20 ±5 °C). The tested extra virgin olive oil samples were stored under conditions simulating domestic and commercial storage environment, in which the impact of light and headspace volume were also examined. Moreover, all the analyzed samples fell within the established "extra virgin olive oil category", thus proving their legitimacy, authentication and excellent quality. Furthermore, all the monitored physicochemical parameters were affected by the progress of the storage period, the rising volume of headspace (due to more available oxygen in the container) and exposition to light, resulting in decreasing quality of the examined extra virgin olive oil samples. In addition, the storage of extra virgin olive oil samples in dark containers reported sufficient resistance to oxidation processes up to a period of 3 months, however, after this period signs of oil quality deterioration were reported. Nevertheless, if exposition to light occurred, accelerated decrease in the quality of the extra virgin olive oil samples was observed

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

Effects of the lactation period, breed and feed on amino acids profile of mare's milk

The effects of the lactation period, breed, and feed on amino acids profile of mare's milk were investigated. The feed contained two major essential amino acids (EAAs) leucine (7.31-10.3 g. kg-1) and arginine (6.37-9.59 g. kg-1); it also included minor EAAs methionine (2.11-3.05 g. kg-1) and histidine (2.48-3.60 g. kg-1). Glu+Gln, Asp+Asn, and proline, major nonessential amino acids (NEAAs), constituted approximately 60% of total NEAAs (TNEAAs). The ratio of total EAAs to NEAAs ranged from 1:1.2 to 1:1.4. Amino acids (AA) content throughout all milk samples varied due to mare's different conditions and lactation days. Except for the 1P milk sample, total AA content in the 2-8Ps specimens caused by differences in breed oscillated from the 2nd to 28th day of lactation within the following limits: 21.9-54.6 g. kg-1, 33.6-70.7 g. kg-1, 38.1-71.2 g. kg-1, 29.46-74.2 g. kg-1, 52.2-87.1 g. kg-1, 37.9-70.3 g. kg-1 and 26.4-64.5 g. kg-1, respectively. In relation to TEAAs in milk, the highest EAAs levels were reached in arginine, leucine and lysine ranging between 2.41-4.35 g. kg-1, 3.36-5.59 g. kg-1 and 2.72-4.80 g. kg-1, respectively, while the lowest AAs amounts were indicated in histidine and methionine, 0.91-1.58 g. kg-1 and 1.23-2.04 g. kg-1 respectively. Total NEAAs content was slightly higher than that of EAAs; the TNEAAs to TEAAs ratio was 1:0.9 proximately. Glu+Gln, Asp+Asn and proline were determined as major NEAAs of milk ranging between, 6.77-11.0 g. kg-1, 3.21-5.60 g. kg-1 and 1.25-2.18 g. kg-1, respectively; levels of NEAAs such as cysteine and glycine oscillated between 0.89-1.52 g. kg-1 and 0.64-1.15 g. kg-1, respectively. The average TAAs contents caused by breed differences were 62.8 g. kg-1, 42.8 g. kg-1, 44.7 g. kg-1 and 44.8 g. kg-1, respectively, on the 2nd, 5th, 10th, and 28th lactation days. © 2020 Potravinarstvo Slovak Journal of Food Sciences