|
|
Analysis of functional properties of protein isolates
Vojtasová, Tereza ; Diviš, Pavel (referee) ; Pořízka, Jaromír (advisor)
Proteins are an important part of the human diet, and a lack of them can lead to many health problems. Therefore, they are often added to enrich foods. For food applications, it is desirable to know the functional properties of the proteins used, as they can significantly affect the resulting quality of the final product. This bachelor thesis was focused on the determination of functional properties of some commercially available protein powders: pea, beef, hemp, rice, egg, soy, whey, and laboratory-prepared wheat bran protein powder, and their possible application in food industry. The theoretical part of the thesis described proteins, their functional properties, production, quality assessment, then plant and animal proteins and methods of characterization of protein isolates and concentrates. In the experimental part, individual determinations of functional properties were performed and their applications in food industry were discussed. The solubility of tested protein powders was variable, with the highest solubility observed in powders of animal origin. The lowest solubility was found at pH 3–5, where the isoelectric point of most proteins was located. Soy protein isolate showed the best water-holding capacity of 10.65 gH2O/g, foaming capacity of 109.6% and emulsion properties. It was followed by pea protein with a WHC of 5.32 gH2O/g. Wheat bran concentrate had the best oil holding capacity of 2.18 goil/g. Foaming properties varied considerably but showed a positive correlation with water-holding capacity. The emulsion activity was very similar for most of the protein powders, except for beef, hemp and rice protein which exhibited no good functional properties. Only the beef hydrolyzed collagen was fully soluble. The emulsion layer increased slightly after heat treatment for the proteins, which already formed quite stable emulsions, except for wheat bran powder. Hemp and bran protein powders were the most distinctive in color, while egg and beef protein powders were the lightest. Soy and pea protein isolates showed foaming and emulsion properties similar to egg white proteins, indicating their potential use as partial or total replacements for egg white proteins in food products. In conclusion, selecting protein isolates with suitable functional and sensory properties for a specific food application is crucial for successful consumer acceptance of the protein-enriched product.
|
|
|
Application of cavitation in industrial processes
Hamar, Oliver ; Tancjurová, Jana (referee) ; Rudolf, Pavel (advisor)
The bachelor thesis deals with the research of the application potential of cavitation technologies in various industries. Thanks to its properties, cavitation seems to be a promising tool for streamlining a large number of industrial processes in several aspects. The first part deals with the theoretical description of the cavitation phenomenon, its negatives and methods of their detection. The second part focuses on the analysis of possible usage areas of cavitation technologies and the ways of generating the cavitation, focusing on current research and findings in the area of hydrodynamic cavitation application.
|
|
|
Application of cavitation in industrial processes
Hamar, Oliver ; Tancjurová, Jana (referee) ; Rudolf, Pavel (advisor)
The bachelor thesis deals with the research of the application potential of cavitation technologies in various industries. Thanks to its properties, cavitation seems to be a promising tool for streamlining a large number of industrial processes in several aspects. The first part deals with the theoretical description of the cavitation phenomenon, its negatives and methods of their detection. The second part focuses on the analysis of possible usage areas of cavitation technologies and the ways of generating the cavitation, focusing on current research and findings in the area of hydrodynamic cavitation application.
|
|
|
Mechanism of the Water Clusters Formation in the Organic Phase in the Presence of Hydrated Ions
Holub, Karel ; Samec, Zdeněk ; Mareček, Vladimír
A two-electrode cell comprising a liquid/liquid interface is used to study the water clusters formation in the organic solvent phase following the extraction of tetraalkylammonium chloride (TAACl) from the aqueous phase. The change in the concentration of the common TAA+ ion on the aqueous side of the interface is monitored by the open circuit potential measurements. It is shown that the amount of TAACl extracted into the organic phase exceeds considerably the limit determined by the concentration of Cl- in the organic phase at a given interfacial potential difference and the electroneutrality condition. A mechanism is proposed including an accumulation of the excess TAACl in the water clusters formed from the hydration shell of the Cl- ions, water already dissolved in the organic phase, and additional water extracted from the aqueous phase. At higher concentration of TAACl in the aqueous phase this process leads to the formation of emulsion in the organic phase.
|
|
|
Electrochemical Monitoring of the Water Clusters Formation in an Organic Solvent in the Presence of Hydrated Ions
Mareček, Vladimír
An electrochemical method has been developed that makes it possible to monitor the\ndynamics of the co-extraction of water with hydrated chloride ions at the interface between\ntwo immiscible electrolyte solutions (ITIES). The interfacial potential was controlled by the\ndistribution of a common tetralkylammonium (TAA+) ion. Changes in the TAA+\nconcentration at the interface were monitored by measuring the open circuit potential (OCP).\nTransfer of hydrated chloride ions is accompanied by the transfer of TAA+, decreasing its\nconcentration on the aqueous side of the interface. This process involves the co-extraction of\nwater molecules with the hydrated chloride ions and the formation of water clusters in the\norganic solvent phase. The ability to monitor the process from the very beginning of interface\nformation allowed us to obtain important kinetic data.
|
|
| |
guest ::
