1. Most spoilage bacteria grow at

A. acidic pH
B. alkaline pH
C. neutral pH
D. any of the pH

2. The microbiological examination of coliform bacteria in foods preferably use

A. MacConkey broth
B. violet Red Bile agar
C. eosine Methylene blue agar
D. all of these

3. Which of the following acid will have higher bacteriostatic effect at a given pH?

A. Acetic acid
B. Tartaric acid
C. Citric acid
D. Maleic acid

4. Which of the following is not true for the thermal resistance of the bacterial cells?

A. Cocci are usually more resistant than rods
B. Higher the optimal and maximal temperatures for growth, higher the resistance
C. Bacteria that clump considerably or form capsules are difficult to kill
D. Cells low in lipid content are harder to kill than other cells

5. Water activity can act as

A. an intrinsic factor determining the likelihood of microbial proliferation
B. a processing factor
C. an extrinsic factor
D. all of the above