Grade A standards:
raw milk for pasteurization
milk from indiv producer can not have more than 100,000 bacteria/mL
after mixing w milk from other producers, no more than 300,000 bacteria/mL
must NOT have detectable abx residues
Grade A standards:
pasteurized milk products
pasteurized cultured products
limit 20,000 bac/mL
coliforms < 10/mL
no limit on total bacteria count
coliforms < 10/mL
manufacturing grade milk standards:
formerly known as
raw milk stds
used for
grade B
milk from indiv producer cannot have more than 1,000,000 bacteria/mL
no more than 3,000,000 bacteria/mL after mixing from diff producers
must NOT have detectable abx residues
only used for cheese, powdered milk, etc
agency responsible for milk safety
FDA
primary tool for regulation and monitoring of milk
grade A PMO (pasteurized milk ordinance)
all raw milk is tested for
beta-lactam antibiotics
residue challenges of dairy industry (4)
*
know them
*
not identifying tx cows and/or tx records
not segregating tx cows (fence jumping)
using common milking equipment or vacuums for tx and healthy cows
failure to observe the milk discard time indicated on the drug label
8 steps of milk processing
filtration / clarification
separation
standardization
pasteurization
flow diversion valve
homogenization
deaeration (or vacuumization)
refrigeration
filtration / clarification
Raw milk pumped under P through a filter to remove visible dirt and foreign particles
Filter does not remove leukocytes or bacteria
Centrifugal clarifier may also be used
separation
centrifugal force separates the lighter cream from the milk serum (skim milk)
standardization
Skim milk and cream are re-mixed to achieve an exact butter fat content of a product (ex 1 % or 2 % milk)
Whole milk has a min of 3.25% butter fat content and skim milk has <0.5% butter fat
pasteurization protocols
HTST
UHT
high temp short time
- 72 C (161 F) 15 seconds
- 16-21 d shelf-life
ultra high temp
- 138 C (280 F) 2 seconds
- shelf-life 2-3 months
flow diversion valve
measures temp of milk >> if below acceptable level diverts to raw milk tank >> goes through process again
homogenization
atomization of milk under high P to break the globules down to apx 2 ug or less
Homogenized milk will not separate, tastes richer and is more digestible
Unit often found bw the regeneration and pasteurization units
deaeration (vacuumization)
expels gases and malodorous volatile substances
used by some plants to remove "feed" flavor (often ass w feeding certain silage) and undesirable odors (ex - wild onion)
refrigeration
once pasteurized >> drop to < 40 F asap to slow deterioration
shelf life dep on temp and time of pasteurization
HTST - 16 to 21 d
UHT - 2 to 3 months
IMP pathogens killed by pasteurization
8 total / 2 most IMP
original pasteurization temps for _________
current temps aimed at __________
Mycobacterium spp (TB) - original pasteurization temp was aimed at this org
Coxiella burnetti - current temps aimed at this organism also
Listeria monocytogenes
Salmonella spp
Campylobacter jejuni
Yersenia enterocolitica
E. coli O157:H7
Brucella spp
remember the two IMP poultry acts
poultry prod inspection act of 1957
- interstate and foreign insepction
wholesome poultry prod act of 1968
- inter and intra-state
common poultry dispositions leading to condemnation
TB
leukosis
Marek's dz
septicemia/toxemia
synovitis
tumor
cadaver
contamination (not allowed to wash off like you can w beef)
overscald
air sacculitis
poultry disposition where only portion of carcass may be condemned
removing bruises - everything else = whole carcass condemned
egg abnormalities leading to condemnation
foreign bodies
blood spot
blood ring
mold
shell crack
abnormal shell
egg abnormality that does NOT lead to condemnation
multiple yolks