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Quiz DM-2 INTRODUCTORY DAIRY MICROBIOLOGY ICAR E-Course

ICAR Offline Ecourse

DM-2 INTRODUCTORY DAIRY MICROBIOLOGY


1. The production of clean, wholesome milk free from pathogens, maintenance of this condition from farm to the consumers is called:





2. The safe foods should not contain





3. Possibility of presence of pathogens is high in





4. The desired texture, flavour of many cheeses is largely due to the development of _____ microorganisms during manufacture and ripening





5. Foods standards indicates that under desirable conditions the numbers of ______ will not ex­ceed certain levels





6. The microorganism responsible for the spread of mastitis among herd is





7. The most common aerobic spores of genus Bacillus not found in milk





8. The predominant genera present in the interior of udder





9. The most common spores found in milk are of





10. The microbial counts of air in sheds should not exceed





11. Personal hygiene of animal handlers means





12. The following practices should be routinely employed to get high quality milk





13. Health of a milk yielding animal will be maintained by checking





14. During storage and transport the following parameters should always be maintained





15. The milker should never be allowed for milking the animal if he is suffering with





16. Ropiness in milk and milk products is generally caused by:





17. Lactic acid bacteria are classified as:





18. Microorganism that can survive to varying extent of pasteurization temperature is





19. Fruity flavour in dairy products is due the contamination of:





20. Lipolytic mold found in milk or its products is





21. According to Sherman’s classification streptococci are classified into __ groups





22. Which of the following is NOT true about Streptococcus pyogenes





23. The significant features of Streptococcus dysgalactiae is _____





24. Lactococcus lactis spp lactis does not





25. Lactococcus lactis spp lactis biovar diacetylactis produces ____ from citrate





26. Homofermentative bacilli having therapeutic properties is





27. A bacilli L. bulgaricus along with a cocci is used for the production of yogurt





28. ________ is a flavour producer in the presence of lactic acid.





29. Life-threatening nosocomial infections in humans, especially in the hospital environment are caused by





30. Pediococcus are





31. Water soluble fluorescent greenish-brown pigment known as ‘Pyoverdin’ is produced by:





32. _______ is an opportunistic pathogen that causes mastitis in dairy animals and human infection.





33. ______ causes ropiness in milk and milk products.





34. ________ is a pseudolactic acid bacteria





35. A natural inhabitant of intestine is:





36. Typhoid is caused by _______________





37. A bacterial species named from Greek meaning the ‘golden grape-cluster berry’





38. The genus having a pathogen known to cause serious diseases in mammals, i.e. tuberculosis, is:





39. An organism that produce yellow to deep orange red carotenoid pigments and used for preparation of surface ripened Limburger type chesses, is:





40. The strain used in cheese making to create CO2 bubbles that become ‘eyes’, round holes in the cheese is:





41. Produces ‘sweet curdling’ by coagulating milk at lower acidity





42. Late blowing condition in cheeses is caused by ______________





43. The main target of milk sterilization





44. Used in the detection of antibiotics in milk





45. A Gram-positive anaerobic spore former





46. The mould generally used for the preparation of blue veined cheeses is_____





47. Bacteriophages are the





48. Aflatoxins are produced by the species of





49. All viruses contains





50. Techniques routinely followed to prevent starter failure are





51. Psychrotrophs are capable of growing:





52. The two predominant psychrotrophic pathogens found in milk products are:





53. The most frequently reported psychrotroph in raw milk.





54. A major spoilage factor of pasteurized stored milk produced by psychrotrophic bacteria





55. The suggested standards of psychrotrophs for satisfactory raw milk are:





56. SPC of very good quality raw milk





57. The DMC of good quality raw milk





58. Thermoduric count of good quality milk





59. Q-fever is caused by





60. It is unlikely that _____ ever live in the udder of an animal.





61. The main cause of spoilage of refrigerated raw milk samples is the production and secretion of _________ and various other thermo-resistant enzymes.





62. The maximum hygienic parameter for fecal coliforms is





63. At low-temperature storages only ___________ will grow that produces heat resistant enzymes that causes off flavour





64. The final quality of a milk product is directly related to hygienic quality of





65. A decrease in temperature from _________ increases the keeping time of milk approximately the same number of days as did cooling from 35-5º C





66. The test provides a rapid indication of the quality of liquid milk products and, at the same time, supplies a permanent record of the quality.





67. The test is insensitive if the bacterial load is very less





68. __________ count is taken at low temperature.





69. Metabolic reactions caused by bacteria are difficult to measure in _____ quality products





70. The electrical impedance in a culture medium remains fairly constant until a threshold of _____ cells per milliliter is reached, when major changes in impedance start to occur





71. The oxidation-reduction potential of good quality milk while testing





72. The number of microbes at the time of decolorizing of methylene blue will be nearly





73. The dye reduction tests are of little value as an index of the bacterial content of





74. The Lovibond comparator is used in





75. The bacteria which reduces resazurin more quickly than methylene blue





76. The method which is useful for a rapid estimation of the total bacterial population (both live and dead cells) of a milk sample is:





77. The indirect method for tracing the sources of contamination of milk is:





78. In DMC, the milk smear is prepared on ___ square centimetre area.





79. In DMC, the milk smear is stained with a special stain called





80. Milk for making smear in DMC test is taken with the help of a sterile





81. The test useful in the estimation of number of viable microorganisms in the given sample of milk





82. The SPC of very good quality raw milk.





83. The purpose of making serial dilutions in this test is aimed to reduce the bacterial number to ____ level while adding to Petri dish





84. The SPC of pasteurized milk





85. The quantity of the previously melted and cooled sterilized standard plate count agar to each Petri dish is





86. Coliforms are Gram's negative, oxidase negative, non-spore forming rods that can grow aerobically or facultative in presence of





87. Coliforms are able to ferment______ with the production of acid and gas within 48 h. at 37°C.





88. Presence of coliforms in milk or milk products indicates, possible contamination with





89. Raw milk is graded/ accepted as criterion of satisfactory quality, based on the absence of coliforms in





90. In addition to the presence of faecal coliforms, the faecal streptococci and Clostridium perfringens are likely to exist in the gut of all warm-blooded animals, and their presence in milk will also indicate the source of faecal contamination. Hence, this coliform test is called as:





91. Micro-organisms capable of growing at refrigeration temperature (7-10°C) are:





92. The media used for the isolation and identification of the proteolytic micro-organisms of milk is:





93. The plates for psychrotrophic count are incubated in a refrigerator at 7-10°C for





94. The Plates for estimating thermophilic microorganisms are incubated at ___ for 24 to 48 h and colonies are counted.





95. Proteolytic psychrotrophic colonies identification can be enhanced by flooding the plates with a solution of





96. The media used for the enumeration of yeast and moulds from milk is





97. The pH of the medium used for enumeration of yeast and mould should be





98. The most important source of contamination of milk with yeasts and moulds is





99. The following is the most important dairy yeast





100. An important mould in dairy industry is:





101. The main goals of all living forms are





102. An interaction between two or more species, where species derive a mutual benefit





103. The relationship between two species which interact but do not affect each other





104. Production of antibiotic or inhibitory substances by one organism that affect the growth or survival of another organism can be called





105. The relationship between microorganisms in which one organism benefits from the association but the other organism is not affected, denotes





106. Micro-organisms that are able to survive the acidity already produced and in turn produce more acidity are:





107. Micro-organism, which may establish itself on the surface of the coagulated milk and oxidize lactic acid to H2O and CO2:





108. When lactose is exhausted the micro-organisms that develop and decompose the casein are:





109. The organic matter like ____ of uncared milk after prolonged storage, has been ‘mineralised’ that is reduced to simple inorganic substances like carbon dioxide, ammonia and hydrogen sulphide:





110. The pH of uncared milk after prolonged storage is:





111. The production of gas mainly CO2 and acid by certain micro-organisms in dairy products is responsible for a defect called:





112. Micro-organism that ferment lactose of milk or cream into gas and acid and cause early gas production:





113. The organism which ferment lactose of milk or cream into gas and acid and cause ‘late gas production’:





114. The lactose fermenting yeast is:





115. Ropy fermentation is brought about by the growth of ____ bacteria leading to change in consistency of the produce that forms threads of viscous masses when poured:





116. The milk obtained from animals suffering from the udder infection is called:





117. The mastitic milk has:





118. Natural inhabitant of udder and mastitis causing micro-organism is:





119. Summer mastitis is caused by:





120. Environmental mastitis is caused by:





121. In case of milk obtained from infected udder, the oxygen liberated with catalase on adding hydrogen peroxide will exceed:





122. CAMP test is very specific for the detection of mastitis caused by:





123. In milk obtained from healthy udder the leucocytes count will be less than:





124. Very long chains of micro-organisms in a smear of mastitic milk is indicative of:





125. Rusty brown colour colonies in Hotis test is indicative of





126. Botulism poisoning is the severest of all the food poisonings, as it affects the _______ and is often extremely fatal:





127. Unhygienic practices appear to be chiefly responsible for the eruption of outbreak:





128. The “infantile diarrhea or Travellers’ diarrhea” characterized by watery diarrhea leading to dehydration & shock is caused by:





129. The common food poisoning caused by canned foods is due to:





130. Alatoxins are mycotoxins produced by:





131. Milk borne tuberculosis is directly or indirectly related to consumption of raw milk from infected dairy herds and the causative microorganism is





132. Corynebacterium diphtheriae is a causative microorganism mainly parasitic to man and is usually found in ________ of the infected or healthy carriers





133. Most heat resistant pathogenic microorganism which can be used as indicator organism for pasteurization





134. Infectious hepatitis is caused by





135. Like many other diarrheal diseases, poliomyelitis occurs commonly in _______ ,





136. Specific naturally occurring anti microbial substances in milk





137. Non-specific naturally occurring anti microbial substances in milk





138. The chief immunoglobulin of milk and confers passive immunity





139. Invading of pathogens by leucocytes for the protection of udder from mastitis





140. The milk contains bifidus factor responsible for the dominance of a bacterium Bifidobacterium bifidus in infants





141. Most pathogenic bacteria are classified as _____________ for their growth temperature requirements





142. Bacteria require nitrogen for the synthesis of _______ :





143. Through metabolism, pathogens often produce acids that interfere with their own growth, hence, ________ are added to media to control pH changes





144. A microorganism that can grow at 4°C and 25°C both but grows best at 20°C would be classified as ______ :





145. Which of the following types of media is designed to suppress the growth of unwanted bacteria and encourage the growth of desired microbes?