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Smart food polymer layers
Valíková, Michaela ; Kovalčík, Adriána (referee) ; Veselá, Mária (advisor)
Smart packaging represents a group of packaging with great potential when used in the food industry. Active packaging can have a positive effect on the condition of stored food and smart packaging can inform consumers about the condition of stored food. In the theoretical part, a search was made on the topic of packaging in the food industry, with emphasis on active and intelligent packaging, including the legislative framework. The substances from which smart packaging is made have been described. In the experimental part, partially water¬insoluble polymer layers were prepared from gelatin, glycerol, crosslinking agent and anthocyanin extract. Glutaraldehyde or tannic acid was used as a crosslinking agent. Anthocyanins were obtained by extraction from red cabbage. The total concentration of anthocyanins in the extract was determined by the difference method. For prepared layers, their water solubility was measured and the colour response to the pH environment was evaluated spectrophotometrically. The stability of the layers over time was also monitored. It was found that the prepared layers are able respond to changes in pH.
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Printed indicator of pH value designed for food packaging
Valíková, Michaela ; Kovalčík, Adriána (referee) ; Veselá, Mária (advisor)
The aim of this diploma thesis was to design an intelligent indicator of pH value for food packaging. Intelligent packaging is a new group of packaging that is able to provide costumers real-time information on the quality of packaged food through various indicators. In the theoretical part, a search was made on the topic of intelligent packaging with emphasis on freshness indicators. A smaller part was devoted to the issue of food spoilage. Emphasis was also placed on the description of the main components of the functional layer, and on the issue of chitosan crosslinking. In the experimental part, the crosslinking of chitosan with the addition of polyvinylalcohol using vanilin was studied. Prepared layers were monitored for their solubility and degree of crosslinking, which was determined using the ninhydrin method. To create a colorimetric pH indicator, an anthocyanin extract obtained by extraction from red cabbage was incorporated into the composition. A total of 3 anthocyanin extracts were prepared, for which the total anthocyanin concentration was determined by the difference method. The color of the prepared layers was evaluated spectrophotometrically under the action of various concentrations of the ammonia gas. The stability of the layers over time was also monitored. The last part of the experiment was the application of the prepared layers in a package with real meat.
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Printed indicator of pH value designed for food packaging
Valíková, Michaela ; Kovalčík, Adriána (referee) ; Veselá, Mária (advisor)
The aim of this diploma thesis was to design an intelligent indicator of pH value for food packaging. Intelligent packaging is a new group of packaging that is able to provide costumers real-time information on the quality of packaged food through various indicators. In the theoretical part, a search was made on the topic of intelligent packaging with emphasis on freshness indicators. A smaller part was devoted to the issue of food spoilage. Emphasis was also placed on the description of the main components of the functional layer, and on the issue of chitosan crosslinking. In the experimental part, the crosslinking of chitosan with the addition of polyvinylalcohol using vanilin was studied. Prepared layers were monitored for their solubility and degree of crosslinking, which was determined using the ninhydrin method. To create a colorimetric pH indicator, an anthocyanin extract obtained by extraction from red cabbage was incorporated into the composition. A total of 3 anthocyanin extracts were prepared, for which the total anthocyanin concentration was determined by the difference method. The color of the prepared layers was evaluated spectrophotometrically under the action of various concentrations of the ammonia gas. The stability of the layers over time was also monitored. The last part of the experiment was the application of the prepared layers in a package with real meat.
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Smart food polymer layers
Valíková, Michaela ; Kovalčík, Adriána (referee) ; Veselá, Mária (advisor)
Smart packaging represents a group of packaging with great potential when used in the food industry. Active packaging can have a positive effect on the condition of stored food and smart packaging can inform consumers about the condition of stored food. In the theoretical part, a search was made on the topic of packaging in the food industry, with emphasis on active and intelligent packaging, including the legislative framework. The substances from which smart packaging is made have been described. In the experimental part, partially water¬insoluble polymer layers were prepared from gelatin, glycerol, crosslinking agent and anthocyanin extract. Glutaraldehyde or tannic acid was used as a crosslinking agent. Anthocyanins were obtained by extraction from red cabbage. The total concentration of anthocyanins in the extract was determined by the difference method. For prepared layers, their water solubility was measured and the colour response to the pH environment was evaluated spectrophotometrically. The stability of the layers over time was also monitored. It was found that the prepared layers are able respond to changes in pH.
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