The effect of added pumpkin flour on sensory and textural quality of rice bread

The impact of added pumpkin flour (1-10 g/100 g) on sensory and textural quality of rice bread was studied on rice biologically leavened rice bread. Specific volume, baking loss, crumb springiness, cohesiveness and resilience decreased with increasing amount of pumpkin flour. The opposite trend was found in crumb hardness and chewiness. Color measurements revealed that the lightness decreased and the greenness increased with increasing amount of pumpkin flour. Bread crumb and crust characteristics were not significantly impacted by the amount of added pumpkin flour. Additionally, the bread taste and flavor were decreased in breads with 8-10 g/100 g of added pumpkin flour, resulting in their lower overall acceptability. Weak impact of added pumpkin flour on sensory evaluation of rice bread may be related to a reduced amount of the panelists involved in this study. The addition of 1-7 g/100 g of pumpkin flour seems to be applicable to rice bread production. More extensive study will, however, be performed to describe the impact of added pumpkin flour on sensory quality of rice bread in more details.[IGA/FT/2017/004

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

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

Impact of alpha-amylase enzyme on the rheological and microstructural properties of the different types of rice flour doughs and bread

The purpose of this study is to discuss the significant role of the alpha-amylase enzyme in the production and rheological characteristics of gluten-free rice dough and baked bread. Small deformation and large deformation methods were used to evaluate the effect of the alpha-amylase enzyme addition on the dough and bread rheological characteristics. The baking properties of bread were evaluated by specific volume, baking loss, and Texture profile analysis parameters. The effect of the added enzyme on the dough microstructure was also evaluated. Small deformation study of doughs showed the highest significant changes after enzyme addition in 0.5S and extra-fine flour doughs. The dynamic rheological study of the flours doughs during the heating period showed significant changes in doughs properties as a function of alpha-amylase. After enzyme addition, a significant difference in crumb hardness was observed in the fine, semi-coarse, and extra-fine bread. After alpha-amylase addition in black rice, 0.5S and extra-fine doughs G', G '' and values were decreased. The research explains how the alpha-amylase enzyme effect the rheological characteristics of gluten-free dough and bread. Rheological analysis of doughs made from flour during the heating period indicated that the properties of the doughs were significantly affected by the presence of alpha-amylase.Univerzita Tomáše Bati ve Zlíně: IGA/FT/2020/21/006internal grant agency Tomas Bata University, Zlin, (Czech Republic) [IGA/FT/2020/21/006

Evaluation and effect of rice bran and microwave heating on the physicomechanical properties of low-density polyethylene film and packaged milk quality

Low-density polyethylene (LDPE) film was developed with a mixture of reference LDPE and rice bran (RB). Three mixtures of 5, 10, and 15% RB were used for the LDPE film preparation. The films were analysed for the physicomechanical properties before microwave heating (MH) and after MH and packaged milk quality was analysed regarding MH and pasteurisation. After MH, the physicomechanical properties of the material change significantly. LDPE film containing 15% RB was created to beat changes in tensile strength, elongation at break, bursting strength, and water vapour transmission rate (WVTR). The total migration of tested packaging materials was within the agreeable limit and after MH it also was within the permissible limit. Four different simulators were used to create food categories. These food simulators included distilled water, 3% acetic acid, 50% alcohol (ethanol), and n-heptane. The obtained results display that the total migration of food packages is dependent on the MH period, package material, and the simulator.Univerzita Tomáše Bati ve Zlíně: IGA/2020/0

The influence of the addition of instant rice mash on the textural properties of rice bread

The effect of instant rice mash (IRC) addition to rice bread was evaluated. Six samples containing different amounts of IRC (0, 10, 20, 30, 40, and 50%) were added to rice dough. Quality parameters (baking loss, specific volume, and textural properties) were evaluated. Texture properties were analysed in fresh bread and in bread after 24 h of storage. Additions of 10% and 20% of IRC increased baking loss from 15% to 22%, and the specific volume of rice bread from 1.5 mL g(-1) to 2.1 mL g(-1) (10% of IRC) and 1.9 mL g(-1) (20% of IRC). Increasing additions of IRC significantly decreased the hardness and chewiness of both fresh bread and bread stored for 24 h. By adding IRC, the cohesiveness of rice bread was increased. These findings are useful for increasing the quality of rice bread by adding IRC to rice dough.Tomas Bata University, Czech Republic [IGA/FT/2021/003

Impact of particle size on wheat dough and bread characteristics

There was studied dough made from refined white and brown wheat flours of different granulometry by means of mechanical, thermal analysis and rheological testing. Observed results were confronted with textural properties of breads. Obtained data confirmed that fine refined white flour dough had high ability to elongate and accumulate stress, in contrary, brown fine flour dough exhibited weaker ability to accumulate stress. Observed increase of the complex viscosity associated with the gelatinization was the fastest in coarse dough, where it gained also the highest peak viscosity. The highest water content liberated was found from fine brown flour bread. This triggered lower water availability for hydration of starch granules in the bread during baking process, thus promoting higher moisture loss affecting thus the overall expansion and porosity of the bread matrix. The latter effect was ascribed to the presence of bran particles in brown flour. © 2019 Elsevier LtdTomas Bata University in Zlin Internal Grant Agency [IGA/FT/2018/003, IGA/FT/2019/006]; Operational Program Research, Development and Education - European Regional Development Fund of the Ministry of Education, Youth and Sports of the Czech Republic [CZ.02.1.01/0.0/0.0/16_019/0000754