Lab exam of raw cows milk

Question 1

Raw cows milk definition:

Answer 1

Milk produced by secretion of the mammary gland of one or more cows not heated over 40*C or undergone treatment of equivalent effect

Question 2

Sensory evaluation of raw cows milk is performed:

Answer 2

In the entrance inspection and output control

Question 3

Parameters should be:

Answer 3

Colour - white with a faint yellow hint
Consistency - homogenous liquid without deposits
Smell and taste - milky, slightly sweet, without foreign smells and flavours
Consistency/texture: smooth and fluid

Question 4

Compilation of a flow diagram:

Answer 4

Visually representing the sequential steps involved in the production, handling and processing of the milk from the cow to its eventual consumption or processing into various dairy products

Question 5

General outline of a flow diagram:

Answer 5

Milking process
Collection and storage
Quality testing - temp, appearance, odour, bact count
Transportation
Processing facilities
Packaging
Storage and distribution
Consumption or further processing

Question 6

Critical control point:

Answer 6

Used in hazard analysis and critical control points systems to identify, monitor and manage potential hazards in food production processes.
Ensure the safety and quality of the milk.

Question 7

What are critical control points?

Answer 7

Milking process - hygiene
Storage temperature - inhibit bact growth
Transportation - temperature + handling
Pasteurization - correct temperature + duration
Packaging and sealing - clean + sealed
Testing and quality control

Question 8

Methods of lab examination:

Answer 8

Standard plate count - total bacterial count
Somatic cell count - primarily WBC
Coliform count - poor sanitation or contamination (MPN - most probable number or membrane filtration)
Pathogen testing - e. coli, salmonella, listeria, campylobacter - PCR
Milk fat, protein and lactose analysis - Gerber, infrared analysis etc.
pH measurement - acidity or alkalinity
Clot-on boiling - coagulation (bacterial contamination/mastitis)
Residue testing - ATB
Cryoscopic exam - freezing point depression (water added etc.)

Question 9

Defects of raw cow milk can be due to:

Answer 9

Poor handling
Environmental conditions
Equipment sanitation

Question 10

Defects of raw cow milk include:

Answer 10

Off-flavours or odour
Contamination (clots, flakes or sediments)
Abnormal colour or appearance
Unbalanced composition
High bacterial count
Presence of residues