Food Microbiology

Question 1

What are the undesirable results of Food?

Answer 1

1. Food Spoilage
2. Textures, Tastes, and Aromas
3. No Nutrient Value
4. Food-borne Illness

Question 2

What are the desirable results of Food?

Answer 2

1. Textures, Tastes, and Aromas
2. Improved Preservation
3. Source of Probiotics (Healthy Bacteria)

Question 3

What is the word used to describe desirable results in Food?

Answer 3

Susceptibility

Question 4

What are the Intrinsic Factors of Food Spoilage?

Answer 4

1. Water
2. Nutrients
3. pH
4. Protective Structures
5. Antimicrobial Constituents

Question 5

Define Intrinsic Factors.

Answer 5

Characteristics of the food itself

Question 6

What is special about water in food spoilage?

Answer 6

Bacteria can’t grow in the H2O portion of the water content that is available and accessible to the microorganism.

Question 7

High CHO in food spoilage can cause what?

Answer 7

Fermentation

Question 8

High Protein in food spoilage can cause what?

Answer 8

Proteolysis

Question 9

What is Proteolysis?

Answer 9

The breakdown of proteins or peptides into amino acids by the action of enzymes.

Question 10

Why is pH so important to bacteria and what pH levels are they happy at?

Answer 10

1. Lower pH is the best
2. High pH too good
3. Most of them love 6.5-7.5

Question 11

Describe the Protective Structures of Food.

Answer 11

1. Dense
2. Dry
3. Low Nutrient
4. Antimicrobial Compound

Question 12

What are Antimicrobial Peptides?

Answer 12

Peptides that kill Gram negative and Gram positive bacteria, enveloped viruses, and fungi

Question 13

What are Phytochemicals?

Answer 13

Any of various biologically active compounds found in plants.

Question 14

What are Terpenes?

Answer 14

Any of a large group of volatile unsaturated hydrocarbons found in the essential oils of plants.

Question 15

What are the Extrinsic Factors of Food Spoilage?

Answer 15

1. Temperature
2. Humidity
3. Packaging
4. Environment (gases)

Question 16

Define Extrinsic Factors.

Answer 16

Storage Conditions

Question 17

Why do we store food in the fridge?

Answer 17

To slow down growth rate of bacteria

Question 18

The greater number cells present on food the what?

Answer 18

Greater effect on food quality

Question 19

What are the 4 phases of the growth rate of bacteria?

Answer 19

1. Lag
2. Exponential Growth
3. Stationary
4. Death

Question 20

What happens during the Lag Phase?

Answer 20

Cell numbers remain fairly constant
A. Metabolically Active
B. Adjust to Environment
C. Repair of Damage
D. Synthesis of Enzymes

Question 21

What happens during the Exponential Growth Phase?

Answer 21

Cell Division proceeds at a constant rate

A. Number of living cells double in a given time

Question 22

What happens during the Stationary Phase?

Answer 22

Conditions become unfavorable to growth
A. Cells stop replicating
B. Run out of nutrients

Question 23

What happens during the Death Phase?

Answer 23

Cells decrease in numbers
A. Loss of Viability
B. Loss of Integrity

Question 24

Match these descriptions to their correct areas of range where food begin to show deterioration.

A. No observable effects
B. Evidence of deterioration
C. Great structural deterioration

Answer 24

A. 10^0-10^6

B. 10^6-10^9

C. 10^9-greater

Question 25

How do we control temperature of food?

Answer 25

1. Cooking
2. Canning
3. Pasteurization

Question 26

What is Pasteurization?

Answer 26

Kill 99-99.9% of pathogens and spoilage organisms without altering taste or texture.