CHAPTER 16: FOOD MICROBIOLOGY Flashcards
1
Q
science that deals with the significance and role of microorganisms in food
A
food microbiology
2
Q
multi-cellular overall fungal body readily visible to the naked eye; cottony or fuzzy in appearance
A
molds
3
Q
mostly unicellular, larger than bacteria ovoid and spheroid in shape
A
yeasts
4
Q
microscopic and single-celled microorganisms
A
bacteria
5
Q
unicellular and multicellular organisms that are photosynthetic or phototropic
A
algae
6
Q
includes the amoeba; not photosynthetic, some are pathogenic
A
protozoa
7
Q
submicroscopic infectious agent, acellular or particulate, obligate parasites
A
viruses
8
Q
sources of microorganisms
A
soil, water, air, plant, animals, food processing equipment
9
Q
initial contact, little or no apparent growth, acclimatized cells
A
lag phase
10
Q
maximal rate of division and population growth of cells
A
exponential phase
11
Q
population growth stops
A
stationary phase
12
Q
decline in population size
A
death phase
13
Q
time that elapses between the formation of a daughter cell and its division into new cells
A
generation time
14
Q
number of generations per unit time usually expressed as generations per hour
A
mean growth rate constant
15
Q
amount of water available in food
A
water activity
16
Q
aw requirement of microorganisms
A
bacteria > yeasts > molds
17
Q
aw for bacteria
A
.87-.97, .91 optimum growth for bacteria
18
Q
aw for molds
A
.6-.87, optimum at .71
19
Q
aw for yeast
A
.6-.9
20
Q
can tolerate high salt concentration
A
halophiles
21
Q
can tolerate high osmotic pressure
A
osmophiles
22
Q
can tolerate low aw or dry environment
A
xerophiles
23
Q
temp ranges for optimum growth of molds
A
25-30 (77-86F)
24
Q
temp ranges for optimum growth of yeasts
A
25-30 (77-86F)
25
extremophilic organisms that are capable of growth and reproduction in low temperature
Psychrophiles or cryophiles
26
temp ranges for optimum growth of Psychrophiles
-5 - -7 C
27
organism that grows best in moderate temperature
mesophile
28
temp ranges for optimum growth of mesophiles
20-45 C
29
organism that grows best in high temperature
thermophiles
30
temp ranges for optimum growth of thermophiles
45-70 C
31
danger zone temp
4.5 - 60 C
32
fastest rate of growth temp
37 C
33
prefer to live in a neutral environment near ph 7
neutrophiles
34
prefer acid medium or ph below 6, cannot thrive on alkaline mdedium
acidophiles
35
live in high ph 9-11
alkalinophiles
36
ph range of microorganisms
bacteria - neutral (6.5 - 7.0)
yeasts - 4-4.5
molds - 2-8.5
37
release energy only in the presence of air or oxygen
aerobes
38
release energy in the absence of air and oxygen
anaerobes
39
can survive with or without oxygen
facultative
40
can survive with little air or oxygen
microaerophilic
41
ingestion of toxins produced by the microorganisms
food intoxication
42
ingestion of massive number of microbial cells
food infection
43
2 stages of bacteria
vegetative stage
resting or spore stage
44
____ is more heat sensitive while in _____ they are more resistant
vegetative stage
resting; spore stage
45
food infection: resistant to drying and freezing
salmonella (salmonellosis)
46
food infection: tolerant to salt; heat resistant
streptococcus faecalis
47
food infection: pathogenic bacteria that can be found in moist environments; can survive and even grown under refrigeration and other preservation measures
listeria monocytogenes
48
food infection: bacteria that is the most common causes of bacterial infections; found in untreated surface waters and intestines of most animals
campylobacter jejuni and coli
49
food infection: associated with travelers' diarrhea
Enterotoxigenic E.Coli (ETEC)
50
food infection: infant watery diarrhea
enterophatogenic E.coli (EPEC)
51
food infection: strains are related to shigella spp, causes dysentry
enteroinvasive E. coli (EIEC)
52
food infection: bloody diarrhea; causes dysentry too
Enterohemorrhagic E. Coli (EHEC)
53
food infection: toxin that damages the intestine causing sever bleeding
shiga toxin
54
food infection: refered to as paralytic shellfish toxins; neurotoxin found in both marine and fresh water environments of life
saritoxin
55
food infection: intestinal infection, primary agent of bacillary dysentry
shigella
56
food infection: halophilic bacterium that is found in esturarine, marine, and coastal environments; leading causal agent of gastroenteritis
vibrio parehaemolyticus
57
food infection: infection caused most often by eating raw or undercooked pork; soil and water borne
yersinia enterocolitica
58
food intoxication: grow in foods that have been cooked, cooled, and held for sometime before eating
clostridium perfringens
59
food intoxication: soil bacteria that thrive on meat, fish, or low acid canned goods
clostridium botulinum (botulism)
60
food intoxication: salt tolerant, fairly tolerant to nitrites, heat resistant, and not killed by pasteurization, can cause gastroenteritis
staphylococcus aureus
61
food intoxication: toxin producing facultatively anaerobic gram-positive bacteria, grow best at room temperature
bacillus cereus
62
mold: black mold
aspergillus niger
63
mold: known to proudce ochratoxin a, one of the most abundant food-contaminating mycotoxins
aspergillus ochraceus
64
baker's yeast
saccharomyces cervisiae
65
uses of yeast
- bread production
- beer and wine
- vinegar
- food fermentation
66
molds use for blue cheese ripening
roqueforti
67
used for making soy sauce and miso
aspergillus oryzae
68
killing, inhibition, removal of microorganisms
disinfection
69
substances that kill or inhibit growth
antimicrobial agents
70
destruction of microbial or vegetative cells or spores
sterlization
71
controling bacterial food poisoning: salmonellosis
heat to 60C(140F) held for 10 mins or higher T, refrigerate at 7C(45F)
72
controling bacterial food poisoning: pefringens poisoning
refrigerate promptly at 4C/40F or below
73
controling bacterial food poisoning: staphylococcal poisoning
temp above or below danger zone
74
controling bacterial food poisoning: botulism
subject food at 121C
75
canning temp for low acid veg, meat, and poultry in PRESSURE canner
121C
76
canning temp for fruits, tomatoes, and pickles in WATER BATH canner
116C
77
cooking temp that destroy most bacteria
100C
78
warming temp that prevents growth but allow survival of some bacteria
74C
79
freezing temp that stops growth of most bacteria
-18C
80
types of spoilage: involves chemical reactions in living organism due to enzymatic reactions.
biochemical spoilage
81
types of spoilage: involves chemical reactions not necessarily involving enzymatic reactions
chemical deterioration and spoilage
82
types of spoilage: due to environmental changes
physical deterioration and spoilage
83
types of spoilage: due to microbial activity
microbiological spoilage
84
types of spoilage: due to pests, insects
macrobiological spoilage
85
contamination caused by helminths, and other parasites, poisonous plants and animals
macrobiological contamination
86
caused by bacteria, yeasts, and molds and their toxins
microbiological contamination
87
contamination caused by fertilizers and pesticides, residue to heavy metals (cobalt, lead, mercury, arsenic, copper)
chemical contamination
88
contamination caused by fragments of insects, animals, etc.
physical contamination
89
contamination with iodine 131, cesium 137, barium 140, stronium 90
radiological contamination
90
field study which deals with conditions and practices in food production, handling, preparation and processing
food sanitation
91
set of guidelines in sanitation. it is recommended in the processing or manufacture, packing and storage of foods to ensure and maintain safety, wholesomeness and quality of food for human consumption.
good manufacturing processes for foods (GMP)
92
preventive system of control particularly that leads to the production of microbiologically foods.
Hazard Analysis Critical Control Points (HACCP)
93
a systematic approach to the identification, evaluation and control of food safety
Hazard Analysis Critical Control Points (HACCP)
94
a collection of internationally recognized standards, codes of practice, guidelines, and other recommendations published by the Food and Agriculture Organization of the United Nations relating to food, food production, food labeling, and food safety.
Codex Alimentarius
