This set of Poultry Products Processing Multiple Choice Questions & Answers (MCQs) focuses on “Microbial Testing of Poultry Meat – Set 2”.
1. Which of the following is used as indicator test on meat products?
a) Total mesophilic count
b) Total aerobic count
c) Total anaerobic count
d) Total protozoa count
View Answer
Explanation: The total mesophilic plate count is used as an indicator test on meat products. It checks the microbiological quality. It is easy method. It cannot be used for fermented meat and milk products. Since the load will be high.
2. What is DEFT?
a) Direct epifluorescent filter technique
b) Direct epifluorescent filter technology
c) Direct epifluorescent filler technique
d) Direct epifluorescent filler technology
View Answer
Explanation: The DEFT stands for direct epifluorescent filter technique. It is a microscopy technique which helps in enumeration of micro-organisms in foods. The technique was developed in response to the need for a rapid method for judging the hygienic quality of the foods.
3. What is MPN method?
a) Most Probable Number
b) Microbial Probable Number
c) Microbial production Number
d) Most Portable Number
View Answer
Explanation: MPN stands for most probable number. It is an alternative method of enumerating low numbers of viable micro-organisms. This method is based on inoculating replicate tubes of an appropriate liquid medium with three different sample sizes.
4. Four ml of Bacterial Culture is added to 36 ml of sterile diluent. From this suspension, two serial, 1/100 dilutions are made, and 0.1 ml is plated onto Plate Count Agar from the last dilution. After incubation, 137 colonies are counted on the plate. Calculate CFU/mL of the original sample?
a) 1.37 x 108
b) 1.37 x 107
c) 1.37 x 106
d) 1.37 x 109
View Answer
Explanation:
Dilution Factor:
Initially 4mL in 36mL = Final Volume / Sample volume = 40/4 = 10.
Then two serial dilutions of 1/100.
Total Dilution Factor = 10 x 100 x 100 = 105
CFU/mL = (no. of colonies x dilution factor) / volume of culture plate
= (137 x 105)/0.1
=1.37 x 108
5. Two ml of Bacterial Culture is added to 18 ml of sterile diluent. From this suspension, three serial, 1/100 dilutions are made, and 0.1 ml is plated onto Plate Count Agar from the last dilution. After incubation, 141 colonies are counted on the plate. Calculate CFU/mL of the original sample?
a) 1.41 x 1010
b) 1.41 x 107
c) 1.41 x 106
d) 1.41 x 109
View Answer
Explanation:
Dilution Factor:
Initially 2mL in 18mL = Final Volume / Sample volume = 20/2 = 10.
Then three serial dilutions of 1/100.
Total Dilution Factor = 10 x 100 x 100 x 100 = 107
CFU/mL = (no. of colonies x dilution factor) / volume of culture plate
= (140 x 107)/0.1
=1.41 x 1010
6. Direct Epifluorescent Filter Technique uses dyes and fluorescent microscopy to rapidly enumerate bacteria on a filter.
a) True
b) False
View Answer
Explanation: Direct Epifluorescent Filter Technique uses dyes and fluorescent microscopy to rapidly enumerate bacteria on a filter. The filter is stained with acridine orange, dried and then counted by epifluorescent microscopy. The results are available in less than 30 minutes.
7. What is the automated version of standard plate count?
a) Spiral plate count
b) Disc plate count
c) Dye plate
d) Electrical plate count
View Answer
Explanation: The automated version of standard plate count is the spiral plater. It is a device that distributes a continuously decreasing volume of liquid over a single rotating agar plate. The agar is then incubated and counts are made.
8. What is CFU/ml, if 105 dilution in the cultural plate yields 120 colonies after incubation where 0.1ml is plated on the sample?
a) 1.2 x 108 CFU/ml
b) 1.2 x 109 CFU/ml
c) 1.2 x 1010 CFU/ml
d) 1.2 x 107 CFU/ml
View Answer
Explanation:
Number of colonies counted = 120
Dilution factor = 105
Volume of cells plated = 0.1 mL
CFU/mL = (number of colonies counted x dilution factor) / volume of bacterial suspension or sample plated
Therefore, CFU = 120 x 105 / 0.1
= 1.2 x 108CFU/ml
9. What is CFU/ml, if 104 dilutions in the cultural plate yields 290 colonies after incubation where 0.1ml is plated on the sample?
a) 2.9 x 108 CFU/ml
b) 2.9 x 109 CFU/ml
c) 2.9 x 1010 CFU/ml
d) 2.9 x 107 CFU/ml
View Answer
Explanation:
Number of colonies counted = 290
Dilution factor = 104
Volume of cells plated = 0.1 mL
CFU/mL = (number of colonies counted x dilution factor) / volume of bacterial suspension or sample plated
Therefore, CFU = 290 x 104 / 0.1
= 2.9 x 107 CFU/ml
10. What is the dilution factor, if the sample has 1.3 x 107 CFU/ml, in the cultural plate yields 130 colonies after incubation where 0.1ml is plated on the sample?
a) 106
b) 105
c) 103
d) 104
View Answer
Explanation:
Number of colonies counted = 130
Volume of cells plated = 0.1 mL
CFU = 1.3 x 107 CFU/ml
CFU/mL = (number of colonies counted x dilution factor) / volume of bacterial suspension or sample plated
Dilution factor = CFU/ml x volume of bacterial suspension or sample/ number of colonies counted
= (1.3 x 107 x 0.1)/130
= 104
11. How much is the culture plate yield, if the sample has 1.5 x 107 CFU/ml, with a dilution factor 104 where 0.1ml is plated on the sample?
a) 150
b) 15
c) 1500
d) 15000
View Answer
Explanation: 104
Dilution factor=
Volume of cells plated = 0.1 mL
CFU = 1.5 x 107 CFU/ml
CFU/mL = (number of colonies counted x dilution factor) / volume of bacterial suspension or sample plated
Number of colonies counted= (CFU/ml x volume of bacterial suspension or sample)/ Dilution factor
= (1.5 x 107 x 0.1)/ 104
= 150
12. 5ml of Bacterial Culture is added to 89 ml of sterile diluent. From this suspension, five serial, 1/100 dilutions are made, and 0.1 ml is plated onto Plate Count Agar from the last dilution. After incubation, 325 colonies are counted on the plate. Calculate CFU/mL of the original sample?
a) 3.2 x 108 CFU/ml
b) 3.2 x 109 CFU/ml
c) 3.2 x 1010 CFU/ml
d) Wrong plate is selected
View Answer
Explanation: The countable plate should be between 30 and 300 colonies in total plate count method. It is difficult to count more than 300. Whereas, less than 30 colonies are too small for a sample size to present an accurate representation of the original sample.
13. What is PCR?
a) Polymerase chain reaction
b) Polymerase change reaction
c) Protein chain reaction
d) Protein change reaction
View Answer
Explanation: PCR standards for Polymerase chain reaction. It is used to test the meat products for Salmonella or Listeria. A large number of samples are screened at a time. The results are obtained rapidly.
14. What is ELSIA test?
a) Enzyme-linked immunosorbent assay
b) Enzyme-linked immunosorbent association
c) Energy-linked immunosorbent assay
d) Enzyme-linked immune assay
View Answer
Explanation: ELISA stands for Enzyme-Linked Immunosorbent Assay. This method is for detecting food allergens. The samples are processed and the change in color confirms the presence of the allergen protein.
15. Qualitative tests results are only given in form of present or absent.
a) True
b) False
View Answer
Explanation: Qualitative tests are the tests where results are only given in form of present or absent. These does not quantify the number of organisms present in the sample. Whereas, the quantitative test the quantity of an microbe present in the sample.
Sanfoundry Global Education & Learning Series – Poultry Products Processing.
To practice all areas of Poultry Products Processing, here is complete set of Multiple Choice Questions and Answers.