1.3

Question 1

Lactic Acid Bacteria - These bacteria produce relatively large quantities of lactic acid from carbohydrates. Species mainly from genera _______, Leuconostoc, Pediococcus, _______, and ________________ are included in this
group.

Answer 1

Lactococcus
Lactobacillus
Streptococcus thermophilus

Question 2

Acetic Acid Bacteria - These are bacteria that produce acetic acid, such as
_________.

Answer 2

Acetobacter aceti

Question 3

Propionic Acid Bacteria - These bacteria produce propionic acid and are used in dairy fermentation. Species such as __________ are included in this group.

Answer 3

Propionibacterium freudenreichii

Question 4

Butyric Acid Bacteria - These bacteria produce butyric acid in relatively large
amounts. Some Clostridium spp., such as ________, are included in this group.

Answer 4

Clostridium butyricum

Question 5

_______ - These bacteria can hydrolyze proteins because they produce
extracellular proteinases. Species in genera ______, _______, Bacillus, Clostridium, ______, Alteromonas, Flavobacterium, Alcaligenes, some in Enterobacteriaceae, and Brevibacterium are included in this group.

Answer 5

Proteolytic Bacteria

Micrococcus
Staphylococcus
Pseudomonas

Question 7

_______ - These bacteria hydrolyze triglycerides because they produce extracellular lipases. Species in genera ______, _______, _______, Alteromonas, and Flavobacterium are included in this group.

Answer 7

Lipolytic Bacteria

Micrococcus
Staphylococcus
Pseudomonas

Question 8

________ - These are bacteria that are able to hydrolyze complex carbohydrates. Species in genera ______, _______, Aeromonas, Pseudomonas, and Enterobacter are included in this group.

Answer 8

Saccharolytic Bacteria

Bacillus
Clostridium

Question 9

______ - These are bacteria that are able to grow at 50°C and above. Species from genera ______, ______, Pediococcus, Streptococcus, and Lactobacillus are included in this group.

Answer 9

Thermophilic Bacteria

Bacillus
Clostridium

Question 10

_________ - These are bacteria that are able to grow at refrigerated temperature (≤5°C). Some species from Pseudomonas, Alteromonas, Alcaligenes, Flavobacterium, Serratia, Bacillus, Clostridium, Lactobacillus, Leuconostoc, Carnobacterium, Brochothrix, Listeria, Yersinia, and Aeromonas are included in this group.

Answer 10

Psychrotrophic Bacteria

Question 11

_______ - They are bacteria that are able to survive pasteurization temperature treatment. Some species from Micrococcus, Enterococcus, Lactobacillus,
Pediococcus, Bacillus (spores), and Clostridium (spores) are included in this group.

Answer 11

Thermoduric Bacteria

Question 12

_________ - They are bacteria that are able to survive high salt concentrations (≥10%). Some species from Bacillus, Micrococcus, Staphylococcus, Pediococcus, Vibrio, and Corynebacterium are included in this group.

Answer 12

Halotolerant Bacteria

Question 13

_____ - These are bacteria that are able to survive at low pH (<4.0). Some species from Lactobacillus, Pediococcus, Lactococcus, Enterococcus, and Streptococcus are included in this group.

Answer 13

Aciduric Bacteria

Question 14

_______ - These are bacteria that can grow in a relatively higher osmotic environment than what is needed for other bacteria. Some species from genera Staphylococcus, Leuconostoc, and Lactobacillus are included in this group. They are
much less osmophilic than yeasts and molds.

Answer 14

Osmophilic Bacteria

Question 15

_______ - These are bacteria that produce gas (CO2, H2, H2S) during metabolism of nutrients. Species from genera Leuconostoc, Lactobacillus, Propionibacterium, Escherichia, Enterobacter, Clostridium, and Desulfotomaculum are included in this group.

Answer 15

Gas-Producing Bacteria

Question 16

______ - These are bacteria having the ability to produce spores. Species from Bacillus, Clostridium, and Desulfotomaculum are included in this group.

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-
-
-

Answer 16

Spore Formers

aerobic spore formers
anaerobic spore formers
flat sour spore formers
thermophilic spore formers
sulfide-producing spore formers

Question 17

_____ - These are bacteria that require oxygen for growth and multiplication. Species from ______, ______, ______ are included in this group.

Answer 17

Aerobes

Pseudomonas
Bacillus
Flavobacterium

Question 18

______ - These are bacteria that cannot grow in the presence of oxygen. Species from _____ are included in this group.

Answer 18

Anaerobes

Clostridium

Question 19

_______ - These are bacteria that are able to grow in both the presence and absence of oxygen. ______, ______, ______, enteric pathogens, and some species of Bacillus, Listeria, Salmonella, Serratia, and coliforms are included in this group.

Answer 19

Facultative Anaerobes

Lactobacillus
Pediococcus
Leuconostoc

Question 20

______ - Species from ______, _______, ______, _______ are included in this group. They are used as an index of sanitation.

Answer 20

Coliforms

Escherichia
Enterobacter
Citrobacter
Klebsiella

Question 21

______ - Pathogenic ______, ______, _______, Yersinia, Escherichia, Vibrio, hepatitis A, and others that can cause gastrointestinal infection are included in this group. Because of the importance of these bacterial groups in
food, many laboratory methods are designed to detect a specific group instead of a specific genus or species. Similarly, control methods are sometimes designed to destroy or prevent growth of a specific group.

Answer 21

Enteric Pathogens

Salmonella
Shigella
Campylobacter