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The thesis process the issue of formation and elimination of acrylamide in foods. Experimentally solves optimization recipe to reduce the content of acrylamide in gingerbread while maintaining the sensory properties. It was verified the effect of three different additives (soda, calcium chloride and citric acid) on acrylamide formation in comparison with the original recipe, which is traditionally used leavening agent ammonium carbonate, which promotes the formation of acrylamide. Combination of all three tested compounds is able to reduce the acrylamide content below the detection limit and simultaneously achieve an acceptable sensory properties. Questions related to some undesirable effects in the rejected variants in tested combinations of additives are discussed.

This essay is about the risks of reporting science through media. We have exemplified the problems with the alarm about acryl amide that came in 2002 through the diffusionist model. From the beginning it was a debate about how dangerous acryl amide is to us humans, but later on it developed to be a debate about whoever did wrong in the intermediation, because later on it came out that acryl amide maybe didn’t cause cancer at all and the scientists didn’t know how to prove if it did or didn’t. In our essay we have based our theories about how the diffiusionist model often is inadequate, with theorists as Stuart Allan, Anders Ekström and Dorothy Nelkin. / Denna uppsats handlar om riskrapportering, där vi exemplifierat problematiken med den linjära spridningsmodellen utifrån akrylamidlarmet som uppstod under 2002. Det var en debatt som kom att handla om hur farligt akrylamid är för oss människor, till att utvecklas till att bli en enda stor debatt om vem som egentligen gjort fel i förmedlingen, då det sedan visade sig att det inte alls var säkert hurvida akrylamid orsakar cancer eller inte. I vår uppsats har vi använt oss av teoretiker som Stuart Allan, Anders Ekström och Dorothy Nelkin, för att styrka våra teorier om att den linjära spridningsmodellen många gånger är bristfällig.

<p>This essay is about the risks of reporting science through media. We have exemplified the problems with the alarm about acryl amide that came in 2002 through the diffusionist model. From the beginning it was a debate about how dangerous acryl amide is to us humans, but later on it developed to be a debate about whoever did wrong in the intermediation, because later on it came out that acryl amide maybe didn’t cause cancer at all and the scientists didn’t know how to prove if it did or didn’t. In our essay we have based our theories about how the diffiusionist model often is inadequate, with theorists as Stuart Allan, Anders Ekström and Dorothy Nelkin.</p> / <p>Denna uppsats handlar om riskrapportering, där vi exemplifierat problematiken med den linjära spridningsmodellen utifrån akrylamidlarmet som uppstod under 2002. Det var en debatt som kom att handla om hur farligt akrylamid är för oss människor, till att utvecklas till att bli en enda stor debatt om vem som egentligen gjort fel i förmedlingen, då det sedan visade sig att det inte alls var säkert hurvida akrylamid orsakar cancer eller inte. I vår uppsats har vi använt oss av teoretiker som Stuart Allan, Anders Ekström och Dorothy Nelkin, för att styrka våra teorier om att den linjära spridningsmodellen många gånger är bristfällig.</p>

The diploma thesis deals with the Influence of the Enzyme L-asparagine and the Inorganic salts (NaCl, CaCl2, NaHCO3 and NH4HCO3) on the elimination of the acrylamide in food-stuffs and a simulated model cereal matrix. The acrylamide belongs to the probable carcinogenic compounds which is incipient in the course of thermal processing of food, which are rich in the reducing sugars and amino acids as L-asparagine. Because of L-asparagine is the natural component of cereals and simultaneously is dominant antecedent incipient acrylamide, the way of the elimination by enzyme L-asparaginase (or the combination of L-asparaginase and salt) leads to the reduced level of acrylamide in a final product. The L- asparagine and salts were used on food-stuffs and a simulated model cereal matrix. It was found that individual used substances (except for NH4HCO3) cause the reduction of acrylamide production even about 90 % without change in the sensory properties of final product.

Quellfähige Verbundwerkstoffe aus Ton und Polyakrylamid können große Quantitäten von Wasser absorbieren, behalten aber dabei eine hohe mechanische Festigkeit und gute Dämpfungseigenschaften und stellen daher eine neue Klasse von Hydrogelen mit potentiell interessanten technologischen Eigenschaften dar. Solche superabsorbierende Verbundwerkstoffe (SAPC) werden durch Polymerisation mit einem Elektronenstrahl oder Bestrahlung mit UV-Licht hergestellt. Die Untersuchung der Eigenschaften von SAPC mit Hilfe von XRD, SEM, DSC, TGA, FTIR und NMR (27Al, 29Si und C) zeigen, dass in der SAPC-Struktur das Akrylamid (AM) mit Montmorillonit in dreierlei unterschiedlichen Weisen verbunden ist: a. AM interkaliert in den Zwischenschichtraum von Montmorillonit in bimolekularen Schichten, die durch van-der-Waals-Kräfte und Wasserstoffbindungen verknüpft sind; b. AM gebunden an der Oberfläche von Montmorillonit durch Wasserstoffbindungen; c. AM als freies Polymernetzwerk. Die Ergebnisse der rheologischen, mechanischen und thermischen Untersuchungen von SAPC zeigen eine völlig vernetzte Struktur mit vergleichsweise hoher mechanischer Festigkeit und thermischer Stabilität. Die Verwendung von SAPC bei der Ölgewinnung (Erhöhung der Ausbeute), im Umweltschutz (Reduzierung sauerer Berge), der Agri- und Silvikultur (Pflanzen, Samenbau), der petrochemischen Industrie (Entwässern), im Bauingenieurwesen (Zementbeimischung) und als Sensorsubstanz demonstriert, dass SAPC ein hohes Potential für umweltfreundliche und wirtschaftliche alternative Zwecke hat.

Quellfähige Verbundwerkstoffe aus Ton und Polyakrylamid können große Quantitäten von Wasser absorbieren, behalten aber dabei eine hohe mechanische Festigkeit und gute Dämpfungseigenschaften und stellen daher eine neue Klasse von Hydrogelen mit potentiell interessanten technologischen Eigenschaften dar. Solche superabsorbierende Verbundwerkstoffe (SAPC) werden durch Polymerisation mit einem Elektronenstrahl oder Bestrahlung mit UV-Licht hergestellt. Die Untersuchung der Eigenschaften von SAPC mit Hilfe von XRD, SEM, DSC, TGA, FTIR und NMR (27Al, 29Si und C) zeigen, dass in der SAPC-Struktur das Akrylamid (AM) mit Montmorillonit in dreierlei unterschiedlichen Weisen verbunden ist: a. AM interkaliert in den Zwischenschichtraum von Montmorillonit in bimolekularen Schichten, die durch van-der-Waals-Kräfte und Wasserstoffbindungen verknüpft sind; b. AM gebunden an der Oberfläche von Montmorillonit durch Wasserstoffbindungen; c. AM als freies Polymernetzwerk. Die Ergebnisse der rheologischen, mechanischen und thermischen Untersuchungen von SAPC zeigen eine völlig vernetzte Struktur mit vergleichsweise hoher mechanischer Festigkeit und thermischer Stabilität. Die Verwendung von SAPC bei der Ölgewinnung (Erhöhung der Ausbeute), im Umweltschutz (Reduzierung sauerer Berge), der Agri- und Silvikultur (Pflanzen, Samenbau), der petrochemischen Industrie (Entwässern), im Bauingenieurwesen (Zementbeimischung) und als Sensorsubstanz demonstriert, dass SAPC ein hohes Potential für umweltfreundliche und wirtschaftliche alternative Zwecke hat.

Snacks are often associated with chips and expanded snack products that generally known for their characteristic texture. These products are normally high in calories with a low content of nutrients and are therefore perceived as unhealthy by many consumers.In addition to their low nutrient content, they might be a source of acrylamide,which has been classified as human carcinogen by the European Food Safety Authority. The growing demand for healthier snack foods has led manufactures to begin experimenting with new processing techniques.  The aim of the study is to evaluate product qualities as affected by two different processing techniques of snack pellets. The more conventional expansion method of deep frying in oilis compared to roasting, using salt as a heat conductor. In order to evaluate the effect of salt-roasting, analyses of salt, fat, water and acrylamide content has been carried out. A sensory triangle test was conducted to determine if there is a difference in texture between snacks expanded using the two processing techniques.  Results indicate that salt-roastingmay have a positive effect by reducing the level of acrylamide in the product. Furthermore, salt-roasting provides a snack pellet with a lower fat content. However, the salt-roasting technique results in a higher salt content in the snack as compared to deep frying. The results from the triangle test shows that there was a significant (p=&lt;0.005) difference between the texture of deep fried and roasted snack pellets. Based on the qualitative commentary of the panelists,  the salt-roasted snack pellets are smaller in size and have a harder and more compact texture compared to the deep fried ones.It is important to point out that results of the study are limited and should only be considered as indications.

Diploma thesis is focused on modification and characterization of polypropylene (PP) products surfaces by the chemical way. In theoretical part of thesis are summarized the current knowledge of this topic including characterization methods. Polypropylene surfaces were modified by acrylic monomers (acrylic acid, acrylic acid with 20 mol% content of sodium acrylate and acryl amide). Modified surfaces were characterized by infrared spectroscopy with ATR technique. The comparative parameter was carbonyl index determined from absorption peaks of functional methyl groups (2950 cm-1 ) and functional carbonyl groups (1700-1750 cm-1) of FTIR-ATR spectra. Determination of effect of initiator concentration on the modification process was done for acetophenone and benzophenone. There were determined the time dependence of carbonyl index for time from 0 to 600 s of mentioned monomers. In the same condition were modified test specimens designed for preparation of adhesive joints. Joints were bonded by cyanoacrylate adhesive that provide reaction with surface of polyacrylic acid. There were founded conditions of modification that provided strength of adhesive joints higher than strength of original PP. There were identified changes of surface roughness by using of confocal microscopy.