Processing Mcirobiology

Question 1

Factors that effect microbial growth

Answer 1

Intrinsic
External
Implicit
Processing

Question 2

Novel Food processes

Answer 2

Minimal processing but maximum preservation

Question 3

Sublethal injury

Answer 3

Any inactivated treatment that does not completely kill microbes
Under right conditions injured cells can grow to full capacity again with pathogenic traits

Question 4

Blanching

Answer 4

Process of scalding prior to freezing for 3 ish mins
Destroys enzymes
Preserves colours and flavours

Question 5

Pasteurisation

Answer 5

Short thermal treatment at high temp
Achieves a 5-7 log reduction
12D would be harmful to the products and not be novel

Question 6

D Valué

Answer 6

Time at a temperature to destroy 90% of target microbes

Question 7

Heat sterilisation UHT

Answer 7

Unit operation which can extend shelf life to excess of 6 months at ambient temples
Heated to sufficient to destroy pathogens and enzymatic activity

Question 8

Canning /bottling

Answer 8

Can achieve total inactivation of micros present
Usually in low acid Food bit can be present but this kills bot too

Question 9

Influences of heat resistance

Answer 9

Type of micros
Incubation conditions
Conditions during heat treatment

Question 10

Medium or high acid foods

Answer 10

Ph determines the d value required to ensure no risk of pathogenic contamination
Application of 12d to low ph foods will cause destruction and have detrimental effects on quality and sensory of food products

Question 11

Extrusion

Answer 11

Reduces microbial load
Inactivated enzymes

Question 12

Microwave and infrared

Answer 12

Absorbed by foods
No direct effect in foods
Due to direct heating losses are variable