Whipping creams are oil-in-water emulsion which by whipping can be formed to a foam by the incorporation of air into the system. Traditionally whipping creams are made out of milk but today imitation whipping creams based on vegetable fat has gained a large share of the marked due to their many benefits compared to traditionally whipping creams. Imitation whipping creams are both cheaper and more flexible than traditionally creams. By vary the characteristics of the fat system and the cream recipe the properties of the imitation creams can be adapted to fit the purpose of a specific product. The aim of this thesis was to increase the understanding of how different types of fat systems and other ingredients affect the properties of imitation whipping creams based on vegetable fat. This was done by studying three vegetable fat systems with different physicochemical properties. The properties of the fat systems were characterized and the three fat systems were then used for making different imitation whipping creams. The properties of the creams were characterized and the properties of the fat systems and the creams were assessed and compared with each other. The study showed that the fat characteristics that generally seem to have the highest impact on the properties of whipping creams are the structure, the solid fat content and the crystallization temperature of the fat. A fat solution with a hard structure, a high crystallization temperature and a high solid fat content at a wide range of temperatures overall seem to provide the whipping creams with the best properties. This as these fat properties provide the creams with a high foam stability, a high overrun and a short whipping time. This study has also shown that other ingredients than the fat systems provide the creams with diverging properties. This is best shown by the results of the freeze-thaw stability which indicate that a recipe with a high amount of sugar seem to provide the whipping creams with good freeze-thaw stability. Other properties of the whipping creams also seem to be very much influenced by other ingredients than the fat systems but further studies are needed to provide clarity to the complexity of the interplay of the ingredients in whipped creams.

A resistência térmica dos microrganismos sofre influência, entre outros fatores, das características do agente e das características do substrato, como o teor de gordura. Um dos objetivos da pasteurização do creme é a eliminação dos patógenos eventualmente presentes no leite. Entretanto, não há padrão de tempo e temperatura de pasteurização para este produto na legislação. O Mycobacterium bovis é considerado o patógeno não formador de esporo de maior resistência térmica que pode normalmente ser transmitido pelo leite. Assim, este trabalho se propõe a avaliar a inativação de Mycobacterium bovis (espoligotipo BR024) em creme de leite fresco submetido a alguns parâmetros comerciais de pasteurização. Creme de leite foi contaminado e pasteurizado em Banho-Maria a 75°C, 80°C, 85°C e 90°C, por 5 e 15 segundos. O agente foi quantificado por semeadura em duplicata das diversas diluições em meio Stonebrink, após incubação a 36°C/45 dias. A redução na população variou de 3,9 log UFC/mL até a 6,8 log UFC/mL o que mostra que, nas condições do estudo, todos os binômios estudados mostraram-se capazes de reduzir a carga contaminante para níveis tão baixos ou menores que 0,1 log UFC/mL, considerando a máxima contaminação inicial natural do leite por M. bovis (4 log UFC/mL), segundo Ball (1943) / The thermal resistance of microorganisms is influenced by the agent in question, the initial microbial load and the characteristics of the substrate that can exert a protective effect on the cell, for example, the fat content. The pasteurization of whipping cream aims to eliminate pathogen microorganisms that may occasionally be present in milk. However, there is no standard in the law of time and temperature for this product, making it necessary more detailed study to consider the specific feature of thermal resistance of microorganisms at different temperatures for pasteurization, especially considering the high fat product. Mycobacterium spp is considered the pathogen spore-non-forming of higher heat resistance that can be transmitted by milk, among species, M.bovis is the most pathogenic. Therefore, this study aims to evaluate the inactivation of Mycobacterium bovis (spoligotype BR024) in fresh whipping cream subjected to some parameters of commercial pasteurization. Whipping cream was contaminated and pasteurized in a water bath at 75°C, 80°C, 85°C and 90°C for 5 and 15 seconds. The agent was measured in duplicate in the middle Stonebrink after incubation at 36°C/45 days. The reduction in the population ranged from 3.9 log CFU / mL up to 6.8 log CFU/ mL which shows that under the conditions of the study, all binomials studied were able to reduce the contaminant load to such low levels or lower than 0.1 log CFU / ml, the maximum initial natural contamination of milk by M. bovis (4 log CFU / mL), according to Ball (1943)

A resistência térmica dos microrganismos sofre influência, entre outros fatores, das características do agente e das características do substrato, como o teor de gordura. Um dos objetivos da pasteurização do creme é a eliminação dos patógenos eventualmente presentes no leite. Entretanto, não há padrão de tempo e temperatura de pasteurização para este produto na legislação. O Mycobacterium bovis é considerado o patógeno não formador de esporo de maior resistência térmica que pode normalmente ser transmitido pelo leite. Assim, este trabalho se propõe a avaliar a inativação de Mycobacterium bovis (espoligotipo BR024) em creme de leite fresco submetido a alguns parâmetros comerciais de pasteurização. Creme de leite foi contaminado e pasteurizado em Banho-Maria a 75°C, 80°C, 85°C e 90°C, por 5 e 15 segundos. O agente foi quantificado por semeadura em duplicata das diversas diluições em meio Stonebrink, após incubação a 36°C/45 dias. A redução na população variou de 3,9 log UFC/mL até a 6,8 log UFC/mL o que mostra que, nas condições do estudo, todos os binômios estudados mostraram-se capazes de reduzir a carga contaminante para níveis tão baixos ou menores que 0,1 log UFC/mL, considerando a máxima contaminação inicial natural do leite por M. bovis (4 log UFC/mL), segundo Ball (1943) / The thermal resistance of microorganisms is influenced by the agent in question, the initial microbial load and the characteristics of the substrate that can exert a protective effect on the cell, for example, the fat content. The pasteurization of whipping cream aims to eliminate pathogen microorganisms that may occasionally be present in milk. However, there is no standard in the law of time and temperature for this product, making it necessary more detailed study to consider the specific feature of thermal resistance of microorganisms at different temperatures for pasteurization, especially considering the high fat product. Mycobacterium spp is considered the pathogen spore-non-forming of higher heat resistance that can be transmitted by milk, among species, M.bovis is the most pathogenic. Therefore, this study aims to evaluate the inactivation of Mycobacterium bovis (spoligotype BR024) in fresh whipping cream subjected to some parameters of commercial pasteurization. Whipping cream was contaminated and pasteurized in a water bath at 75°C, 80°C, 85°C and 90°C for 5 and 15 seconds. The agent was measured in duplicate in the middle Stonebrink after incubation at 36°C/45 days. The reduction in the population ranged from 3.9 log CFU / mL up to 6.8 log CFU/ mL which shows that under the conditions of the study, all binomials studied were able to reduce the contaminant load to such low levels or lower than 0.1 log CFU / ml, the maximum initial natural contamination of milk by M. bovis (4 log CFU / mL), according to Ball (1943)