Milk Hygiene Flashcards Preview

RUSVM Epidemiology > Milk Hygiene > Flashcards

Flashcards in Milk Hygiene Deck (24)
1

composition of cow milk

mixture of fats, proteins, carbohydrates, minerals, vitamins and water

2

NCIMS

National Conference on Interstate Milk Shipments

3

grade A milk

defined and regulated by the Pasteurized Milk Ordinance
milk for liquid consumption and any milk in interstate commerce
cheese, butter, ice cream and other dairy products are made from Grade A

4

True/False: milk is biologically sterile

False:
- mastitis organisms
- bacteria in the teat canal
- bacteria from the skin of the teat
- post-harvest contamination

5

causes of high bacterial counts

Milking dirty cows
Cleaning water temperature and volume
Cracked rubber parts
Dirty gaskets
Biofilm, particularly in bulk tank
Inadequate cleaning of bulk tank.
mastitis bacteria

6

sanitation

starts with the premises (milking parlor, equipment, yard/pasture)
cows (udder, flanks bellies, tails; teat dip)
personnel (hand washing!)

7

storage

Milk is stored on the farm in refrigerated, usually stainless steel, bulk milk tanks
Under the PMO milk may be stored for up to 4 days in this tank

8

transport

insulated tanker trucks
tested for antibiotic residues before it is unloaded
may pick up from more than one farm

9

milk receiving station

Milk is analyzed for bacteria, somatic cell counts, and composition (fat and other components)

10

clarifier

remove sediment
Removes dirt, straw, blood, somatic cells, manure, NOT bacteria

11

separator

separate milk with different amounts of fat

12

pasteurization

Brief heating is used to kill common pathogens in milk; milk is not sterile
Pasteurization is currently based on the thermal death of Coxiella burnetii

13

Batch pasturization

Entire vat is heated and held at temperature for the appropriate length of time

14

continuous-flow pasturization

Milk flows through a heated tube, with a carefully monitored transit time and temperature
Less of a “cooked” flavor than seen with batch methods

15

true/false: for cheese and cottage cheese there is no bacterial limit

true; coliform

16

after pasteurization

Cooled to

17

sources of microbes

Udder: infections of the udder
Exterior of animal: dirt/mud, feces, hair, etc.
Air: dusts, aerosol, etc
Milking equipment
Personnel
Water

18

mastitic milk

Increased blood proteins and leukocytes in milk
Decreased milk yield

19

true/false: 5-10% of cows may produce abnormal milk at any one time

true

20

mastitis cases=

high SCC and low production

21

legal maximum SCC for Grade A cow’s milk in the USA

750,000 cells/mL

22

#1 cowside test for mastitis

California mastitis test (CMT)

23

mastitis screening test

California mastitis test (CMT)
Electrical conductivity
Mammary associated amyloid A
Bacteriologic cultures

24

sale of unpasteurized milk

Belief that nutrients are lost by pasteurization
Belief that pasteurization causes milk allergies
Illegal in most states
“Cow- Shares”