Segurança Alimentar e Atividade Microbiana

<p>7,2 (A)</p> Signup and view all the answers

<p>5,5-8,5 (C)</p> Signup and view all the answers

<p>Mudanças de temperatura (A), Quantidade de água no produto (D)</p> Signup and view all the answers

<p>Intrínsecos e extrínsecos (C)</p> Signup and view all the answers

<p>Prever quais microrganismos alteram os alimentos (A)</p> Signup and view all the answers

<p>Umidade do alimento (B)</p> Signup and view all the answers

<p>Diminui a atividade microbiana e evita contaminação (B)</p> Signup and view all the answers

<p>As bactérias não se multiplicam em ambientes ácidos. (C)</p> Signup and view all the answers

<p>Bolores xerófilas (C)</p> Signup and view all the answers

<p>0,91 (C)</p> Signup and view all the answers

<p>Lácteos e carnes (A)</p> Signup and view all the answers

<p>Define a quantidade de água disponível para os microrganismos. (C)</p> Signup and view all the answers

<p>Leites fermentados (A)</p> Signup and view all the answers

<p>Fungos (C)</p> Signup and view all the answers

<p>Inibição do crescimento. (C)</p> Signup and view all the answers

<p>Diminuir a deterioração dos alimentos. (C)</p> Signup and view all the answers

<p>Aumento da temperatura de cocção. (C)</p> Signup and view all the answers

<p>Crescem em alta pressão osmótica e preferem ambientes secos. (D)</p> Signup and view all the answers

<p>Elas perdem água e plasmolizam. (B)</p> Signup and view all the answers

<p>Aumentam a concentração osmótica no ambiente exterior. (B)</p> Signup and view all the answers

<p>Crescer em alta pressão osmótica, geralmente em ambientes doces. (B)</p> Signup and view all the answers

<p>Halófilos extremos. (B)</p> Signup and view all the answers

<p>Sua capacidade de perder ou ganhar elétrons. (D)</p> Signup and view all the answers

<p>Microrganismos que crescem entre 10-50°C. (B)</p> Signup and view all the answers

<p>A maioria dos microrganismos patogénicos para humanos é mesófila. (C)</p> Signup and view all the answers

<p>Lactenina. (A)</p> Signup and view all the answers

<p>Inibir o Clostridium butyricum. (A)</p> Signup and view all the answers

<p>Tegumentos das sementes. (C)</p> Signup and view all the answers

<p>O tempo para eliminar 90% da população de microrganismos. (A)</p> Signup and view all the answers

<p>Staphylococcus. (A)</p> Signup and view all the answers

<p>Proteus vulgaris. (C)</p> Signup and view all the answers

<p>Vitaminas do complexo B. (C)</p> Signup and view all the answers

<p>O tempo necessário para reduzir a população de microrganismos viáveis em 90% (A)</p> Signup and view all the answers

<p>Representa 1 microrganismo entre 1000 em um processo de aquecimento (C)</p> Signup and view all the answers

<p>Z é o aumento necessário na temperatura para reduzir D em um ciclo logarítmico (C)</p> Signup and view all the answers

<p>Aumentos na temperatura geralmente diminuem o tempo necessário para a redução (C)</p> Signup and view all the answers

<p>A resistência térmica do microrganismo em questão (B)</p> Signup and view all the answers

<p>São pouco ácidos, com pH maior que 5,0 (B)</p> Signup and view all the answers

<p>Temperaturas elevadas podem aumentar a letalidade de microrganismos (D)</p> Signup and view all the answers

<p>Reduzir o teor a 10D (B)</p> Signup and view all the answers

<p>Populações maiores tornam a eliminação mais difícil (C)</p> Signup and view all the answers

<p>São vistos como probabilidades de sobrevivência (D)</p> Signup and view all the answers

Factors influencing the growth of microorganisms in food, categorized as intrinsic or extrinsic.

Characteristics of the food itself affecting microbial growth, like pH, water activity, and nutrients.

Environmental conditions affecting microbial growth, such as temperature, humidity, and presence of oxygen.

Methods to control microbial growth and extend the shelf life of food.

Identifying likely microbes to change food, to act on a specific food product for safety.

Most bacteria thrive in a pH range of 6.5 to 7.5, though many cannot survive below pH 4.

Different microorganisms have specific optimal pH ranges for growth. Bacteria typically are more sensitive to pH levels than fungi.

Microorganisms that thrive in acidic environments, with optimal pH between ~1.0 and ~3.0.

The pH level significantly affects the growth of microbes, and different microbes have wider or narrower pH growth ranges.

Fungi typically grow best in a pH range of 5 to 6.

A measure of acidity or alkalinity, affecting microbial growth. Lower pH inhibits some bacteria.

Inhibits the growth of some microbes, e.g., bacteria. Acidic foods, like fruit, are less easily contaminated.

Measure of the amount of water available for microbial growth.

Microbial growth depends on the available water (aw). Different microbes need different levels of aw.

The lowest water activity required for the growth of a specific microbe group

Most bacteria need higher water activity to grow (typically above 0.91).

Molds can grow with lower water activity than bacteria (lower than 0.8).

Lowering water activity and or pH, through methods like drying or adding acid, prevents microbial growth and extends shelf life.

A measure of the availability of water in food for microbial growth.

Methods to decrease the amount of water available for microbial growth in food.

Shrinking of microbial cells due to water loss when surrounding solution is more concentrated.

The pressure that develops in a solution when water moves from an area of high water concentration/lower solute concentration to an area of low water concentration/higher solute concentration. High osmotic pressure draws water out of cells.

Microorganisms that thrive in environments with low water activity.

Microorganisms that tolerate high osmotic pressure, often associated with high sugar.

Microorganisms requiring salt for growth.

A measure of the tendency of a substance to gain or lose electrons.

Microorganisms that thrive in cold temperatures, usually between -8°C and 20°C, with an optimal growth temperature around 10°C.

Microorganisms that grow best in moderate temperatures, typically between 10°C and 50°C, with an optimal temperature around 37°C.

Microorganisms that grow best in high temperatures, around 40°C to 73°C, with an optimal temperature around 65°C.

Environmental aspects influencing food microbial growth, such as temperature, humidity, oxygen, and gas concentration.

Time taken to reduce a microbial population by 90% at a specific temperature.

Mesophilic microbes that can grow at lower temperatures than their optimal range.

Decomposition of food by microorganisms, often leading to changes in taste, texture, and appearance.

Different microbes have optimal temperature ranges for growth, ranging from cold to hot.

Resistant structures produced by some bacteria, particularly Bacillus and Clostridium. They survive harsh conditions.

Substances that prevent or kill microorganisms, naturally present in some foods or produced by microorganisms.

The time (in minutes, seconds) required to kill 90% of a microbial population at a specific temperature.

The change in temperature (in °C) required to reduce the D-value by a factor of 10 or a 1-log reduction in microbial population.

A D-value of 1.5 seconds means 90% of the target bacteria is killed in 1.5 seconds under specific temp conditions

Capacity of a microbe to tolerate exposure to a given agent. For microorganisms, this can be expressed as the time needed to kill a certain percentage or a specific number of microorganisms.

The process of killing microorganisms by exposing them to elevated temperatures.

A thermal process used to kill disease-causing microorganisms in food and beverages.

Indicates the relationship of temperature on the rate of microbial killing

Reducing the pH of the food, often resulting in decreased microbial growth.

Categorization of foods based on their acidity (pH) levels impacting the effectiveness of heat treatments

The degree to which microbes are susceptible to heat-based killing methods.