Microbiology

Question 1

what are the three outcomes of microbes in food?

Answer 1

pathogenesis, spoilage, preservation

Question 2

What are characteristics of colony morphology? (macroscopic)

Answer 2

form, margin, elevation, size, pigment, optical characteristics, texture

Question 3

what are the major cell morphologies? (microscopic)

Answer 3

cocci, rod (bacillus), spirillum, spirochetes, appendaged, filamentous

Question 4

gram positive stains ___, gram negative stains ___

Answer 4

purple; pink

Question 5

this traps the stain

Answer 5

peptidoglycan

Question 6

what are the 4 phases of bacterial growth?

Answer 6

lag, exponential, stationary, death

Question 7

what is the lag phase?

Answer 7

interval between when culture is inoculated and when growth begins

Question 8

what is the most desirable stage for study of bacteria for enzymes?

Answer 8

exponential phase

Question 9

which phase is associated with waste production?

Answer 9

stationary phase

Question 10

these are highly resistant to heat, easily dispersed, hard to destroy

Answer 10

endospores

Question 11

what are 4 parts of spore?

Answer 11

core, cortex, coat, exosporium

Question 12

outermost layer of spore, thin protein covering

Answer 12

exosporium

Question 13

loosely cross-linked peptidoglycan

Answer 13

cortex

Question 14

contains core wall, cyto membrane, cyto, nucleoid, ribo

Answer 14

core

Question 15

core is high in ____ acid, and ____ proteins

Answer 15

dipicolinic; small acid soluble

Question 16

cytoplasm in endospore core contains ___% of water found in vegetative cell, pH is __ unit lower

Answer 16

10-25; 1

Question 17

examples of bacteria that don’t form spores

Answer 17

e coli and s. aureus

Question 18

molds multiply by spores known as ___

Answer 18

conidia

Question 19

these can’t be cultured on plates and must be detected directly; single celled eukaryotes

Answer 19

protozoan parasites

Question 20

obligate parasites that are host specific, transmitted fecal/orally

Answer 20

food borne virus

Question 21

sources of microbes in food?

Answer 21

soil/water, plants, food utensils, GI, mamary tissue, food handlers, animal feed, animal hide, air/dust

Question 22

biggest source of microbes in foods?

Answer 22

soil and water

Question 23

fresh cut meats have ___ cells/gram microbes, comminuted (ground up) meats have ____ cells/gram

Answer 23

10^3; 10^6

Question 24

contamination occurs primarily during ___

Answer 24

harvesting

Question 25

____ can eliminate pathogens

Answer 25

composting

Question 26

raw milk typically has ______ cfu/mL bacteria

Answer 26

100-100 000

Question 27

alpha 1-4 polymers of galacturonic acid

Answer 27

pectin

Question 28

beta 1-4 glucose polymers

Answer 28

cellulose

Question 29

alpha 1-6 glucose polymers that alter texture/flavour (slime)

Answer 29

dextrans

Question 30

do microbes target proteins or carbs first?

Answer 30

carbs

Question 31

what are examples of biogenic amines?

Answer 31

cadaverine, putrescine

Question 32

what are factors that affect microbial growth?

Answer 32

nutrients, water activiy, temp, o2, pH, physical props (SA, exudates, natural barriers), applied ingredients (nitrite, salt, sugar, smoke, acids, spices)

Question 33

what is hurdle approach?

Answer 33

multiple parameters are employed to obtain growth inhibition (combine)-->less extreme

Question 34

milk at pH ___ form gel, at pH __ forms precipitate of protein

Answer 34

5.2; 4.6

Question 35

production of yogurt takes __ hr

Answer 35

6

Question 36

making sauerkraut, add __% salt

Answer 36

2.5

Question 37

infective dose of e. coli and salmonella is ____, for shigella is ____

Answer 37

10^5; 10

Question 38

what are the 4 diff pathogenic microorganisms?

Answer 38

bacteria, fungi, parasites, viruses

Question 39

fecal oral transmission routes

Answer 39

hands/person to person; insects, water, crops, soil

Question 40

fever caused by ___

Answer 40

pyrogen

Question 41

viruses to know?

Answer 41

hep A, noro, rota

Question 42

this bacteria is everywhere

Answer 42

listeria

Question 43

rice contains ____ toxin

Answer 43

cereulide

Question 44

aspergillus flavus creates ___

Answer 44

mycotoxins

Question 45

secondary metabolites that are "fungal poison"

Answer 45

mycotoxins

Question 46

produces alkaloid toxin, that causes hallucination, known as "St. Anthony's fire"

Answer 46

claviceps

Question 47

if grain has > ___% C. purpurea by weight it is considered ___

Answer 47

0.3; ergoty

Question 48

yellow rice caused by ___ and causes severe ___ damage

Answer 48

penicillium; liver

Question 49

Turkey X disease caused by _____

Answer 49

aflatoxin

Question 50

what is ATA?

Answer 50

Alimentary Toxic Aleukia, consumption bread contaminated w/ trichocenes from Fusarium-->cause dermal necrosis, hemorrhage, bone degrade

Question 51

What is e.coli that produces toxin?

Answer 51

EHEC; esp O157

Question 52

what are EHEC symptons?

Answer 52

Hemolytic uremic syndrome (hemolytic anemia, thrombocytopenia, renal fail), bloody diarrhea, nausea/vomiting, fever (rare), severe cramps, thrombotic thrombocytopenia purpura

Question 53

incubation of EHEC is ___ days, symptoms last _____ days

Answer 53

4; 7-10

Question 54

ice can contain ____ virus

Answer 54

hep A

Question 55

virus common on cruise ships that has long latency period

Answer 55

norovirus

Question 56

proteins that are very difficult to kill; examples include scrapie, BSE, chronic wasting disease

Answer 56

prions

Question 57

what does HACCP stand for?

Answer 57

Hazard Analysis Critical Control Point System

Question 58

what are trends in processing?

Answer 58

centralization; greater distances and increased holding times

Question 59

what are the 7 principles of HACCP?

Answer 59

1) assess hazards 2) determine critical control points 3) establish critical limits 4) establish procedures monitor CCP 5) establish corrective actions 6) establish procedures that verify plan working 7) effective record/doc system

Question 60

what is FSEP?

Answer 60

Food safety enhancement program, include HACCP but extends beyond to entire food enviro before HACCP implementation, in CFIA

Question 61

what are GMPs?

Answer 61

Good Manufacturing Practices

Question 62

FSEP and HACCP now required in all federally registered ______ establishments

Answer 62

meat/poultry