Microbial Growth & Food Spoilage

<p>Cutting melons introduces bacteria to the flesh, and their pH supports bacterial growth. (C)</p> Signup and view all the answers

<p>Risk of botulism due to anaerobic conditions. (B)</p> Signup and view all the answers

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

<p>Exponential growth (D)</p> Signup and view all the answers

<p>Minimizing the time food spends in the log phase of microbial growth. (C)</p> Signup and view all the answers

<p>The presence of multiple interacting microbial species. (D)</p> Signup and view all the answers

<p>20,500 (C)</p> Signup and view all the answers

<p>30 minutes (C)</p> Signup and view all the answers

<p>Contamination introduced during harvesting, followed by variable storage conditions. (D)</p> Signup and view all the answers

<p>Microbial interactions can alter growth rates and survival compared to pure cultures. (D)</p> Signup and view all the answers

<p>It increases the Eh due to the oxidizing properties of oxygen. (D)</p> Signup and view all the answers

<p>pH 6.0 - 8.0 (A)</p> Signup and view all the answers

<p>Low water activity inhibits microbial growth, extending shelf life. (B)</p> Signup and view all the answers

<p>They act as a barrier to prevent or slow down microbial entry. (A)</p> Signup and view all the answers

<p>By utilizing foods as a source of nutrients and energy. (A)</p> Signup and view all the answers

<p>They are processing factors that can either promote or inhibit microbial growth. (C)</p> Signup and view all the answers

<p>100 times more acidic (C)</p> Signup and view all the answers

<p>Viable cells remain colorless as they reduce the dye. (B)</p> Signup and view all the answers

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

<p>Decreases Eh, favoring the growth of obligate anaerobes. (A)</p> Signup and view all the answers

<p>Acts as an antimicrobial agent (A)</p> Signup and view all the answers

<p>Free water is easily extracted from foods, while bound water is not (C)</p> Signup and view all the answers

<p>To influence the redox potential and microbial growth (D)</p> Signup and view all the answers

<p>By using redox dyes to determine the proportion of viable cells in the yeast (B)</p> Signup and view all the answers

<p>Entrapped water promotes microbial growth once released due to damage (B)</p> Signup and view all the answers

<p>Each reaction governing food spoilage has a unique temperature dependence. (D)</p> Signup and view all the answers

<p>Increasing the storage temperature of the food. (D)</p> Signup and view all the answers

<p>Risk of spoilage from most bacteria, yeasts, and molds. (A)</p> Signup and view all the answers

<p>By creating a series of suboptimal conditions that inhibit microbial growth. (D)</p> Signup and view all the answers

<p>It determines the availability of water for microbial growth and chemical reactions. (A)</p> Signup and view all the answers

<p>Increasing the salt concentration to reduce water activity. (B)</p> Signup and view all the answers

<p>Freezing immobilizes water and lowers $A_w$, but the effect is reversible upon thawing. (B)</p> Signup and view all the answers

<p>Properties inherent to the microorganisms affecting their survival and growth. (A)</p> Signup and view all the answers

<p>They support the growth of infectious or toxin-producing microorganisms and are consumed without further cooking. (D)</p> Signup and view all the answers

<p>By dissolving in water to form carbonic acid, thus reducing pH. (C)</p> Signup and view all the answers

<p>To predict the potential for microbial growth and spoilage. (D)</p> Signup and view all the answers

<p>Salt ionizes and attracts more water molecules due to its chemical structure. (C)</p> Signup and view all the answers

<p>RH influences water transfer between the produce and the environment, affecting turgor and spoilage. (C)</p> Signup and view all the answers

<p>Organisms previously exposed to stress may exhibit increased heat resistance. (A)</p> Signup and view all the answers

<p>To prevent the growth of pathogenic bacteria that can cause foodborne illness. (B)</p> Signup and view all the answers

A graph describing the growth of microorganisms over time, showing distinct phases.

The initial phase of the microbial growth curve where cell division has not yet started.

The phase of exponential growth where microbial population doubles at a constant rate.

The phase where the growth rate slows and the number of living cells stabilizes due to resource limitations.

The phase where the rate of cell death exceeds the rate of new cell formation.

The rate at which a microbial population grows during the log phase, quantified as the slope of the log curve.

The time it takes for a microbial population to double in number, varies among species.

The origins of microbes that can introduce unwanted microorganisms into food during various stages.

Foods that are more susceptible to bacterial growth and food poisoning.

Melons like cantaloupe that become high risk once cut, allowing bacteria to spread.

Main factors leading to food poisoning include inadequate cooling and cross-contamination.

Failure to cook food thoroughly, allowing harmful bacteria to survive.

Transfer of harmful bacteria from raw foods to ready-to-eat foods.

Factors that are inherent to the food, affecting microbial growth.

External conditions that influence microbial growth, like temperature and humidity.

Methods used to prepare foods that impact microbial growth, such as cooking or packaging.

A measure of acidity or alkalinity in foods, affecting microbial growth rates.

Bacteria generally thrive best in a pH range of 6.0 - 8.0.

Yeasts grow best in a pH range of 4.5 – 6.0.

The tendency of a substance to accept or donate electrons, influencing microbial growth.

Microorganisms that require oxygen to grow, thriving in high redox potential.

Microorganisms that thrive in low or negative redox potentials and require no oxygen.

Water that can be easily extracted from food, important for microbial growth.

Water that is not easily removed from food, less available for microbial growth.

A measure of the amount of water available for microbial growth in food.

Substances in food that inhibit microbial growth, such as garlic compounds.

The available nutrients in food that support the growth of microorganisms.

Water affects food's texture, impacting crispness or tenderness.

A measure of how much water in a food is available for microbial growth, ranging from 0.0 to 1.0.

The increase in number of microorganisms, which is affected by water activity and temperature.

Methods used to control microbial growth by altering water activity or acidity.

An Aw of less than 0.85 minimizes bacterial growth, according to the FDA.

The ideal range where microorganisms grow best, usually around 20°C to 45°C for mesophiles.

Minimum, optimum, and maximum temperatures at which microorganisms can grow.

The temperature range (4°C - 60°C) where bacteria grow rapidly.

Using multiple sub-optimal conditions to inhibit microbial growth in food.

Packaging technique that alters the atmosphere around food to slow spoilage.

The process of removing water from food to decrease water activity.

Freezing food immobilizes water and decreases effective water activity.

A survival mechanism for certain microorganisms that allows them to withstand extreme conditions.

Grouping of microorganisms based on temperature preferences and growth behavior.