Connect Quiz Chapter 29

Johnny buys a package of fresh-sliced ham from the deli and places it in his refrigerator. Unbeknownst to him, there are 10,000 E. coli cells on his ham. After three days under refrigeration, predict the number of E. coli cells that would be on his ham, using what you know about the effects of refrigeration on most microbes. a. 0 b. About 100 c. Slightly more than 10,000 d. About 1,000,000,000

c. Slightly more than 10,000

The ripening process during cheese production _________. a. is used to kill harmful bacteria in the food before consumption b. uses secondary bacteriophages to destroy the initial bacteria used in the production process c. employs metabolic activities of other microbes to produce texture and flavor changes in the cheese over time d. exposes cheese to air to oxidize it gradually over time, changing its consistency depending on the amount of time it's exposed to air

c. employs metabolic activities of other microbes to produce texture and flavor changes in the cheese over time

The main environmental factors that affect microorganism growth include chemical inhibitors, oxygen, pH, nutrients, moisture, and ________. a. food texture b. time c. temperature d. cleaning agents

c. temperature

Food packaging can be extremely influential in how long it takes for a food to spoil. What type of food would take the longest to spoil? a. A tomato b. A plastic bag of shredded cheese c. Egg yolks in a glass jar d. Ham slices in modified atmosphere packaging

d. Ham slices in modified atmosphere packaging

A 2018 outbreak at a popular Ohio fast-casual chain restaurant left over 600 people sick. The CDC confirmed the presence of a toxin from Clostridium perfringens in the stool samples of affected individuals. What symptoms would the individuals have suffered? a. Cramps and diarrhea within a day and lasting for 24 hours b. Headaches and vomiting, with dizziness c. Fainting, headaches, and high fever d. Fever, headaches, and nausea

a. Cramps and diarrhea within a day and lasting for 24 hours

Which of the following statements is false regarding the control of microbial growth by altering the availability of water? a. Foods with a high sugar content such as honey, jams and jellies, and syrup, have a high aw value, which eliminates the growth of microbes. b. Dried foods have minimal available water for organisms, however, xerophiles thrive in these dry environments. c. Foods with a high sugar content have low aw values, however osmophiles can still spoil these foods. d. Foods with a high salt content dehydrate nonhalophiles because of high osmotic pressure, preventing spoilage by most organisms.

a. Foods with a high sugar content such as honey, jams and jellies, and syrup, have a high aw value, which eliminates the growth of microbes.

Above 100°C (212°F) most bacteria _________. a. are destroyed b. stop growing, but are not dead c. are not affected by the heat d. grow rapidly

a. are destroyed

Pasteurization is the use of heat to kill both pathogens and spoilage organisms. It's commonly used for treatment of milk. For the high-temperature, short-time (HTST) process, milk is treated at ________. a. 62.8oC for 30 minutes b. 72oC for 15 seconds c. 138oC for 2 seconds

b. 72oC for 15 seconds

At freezing temperatures, most bacteria ________. a. are destroyed b. stop growing, but are not dead c. are not affected by the cold d. grow rapidly

b. stop growing, but are not dead

Currently, the CDC's PulseNet program is in operation to track food-borne pathogens back to their source. Thanks to efficiency and lower costs, this program is likely to be replaced by __________. a. DNA fingerprinting b. whole-genome sequencing c. ELISA d. immunomagnetic beads

b. whole-genome sequencing