NZQA Expiring unit standard
4827 version 6
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Title
Explain general microbiology and the control of microbes in the dairy
industry
Level
4
Credits
4
Purpose
People credited with this unit standard are able to: explain the
three main types of microbes of importance to the dairy
industry; explain factors affecting microbial growth and the use
of these factors to control microbial growth; explain the
microbiological control of dairy products; explain routine
microbiological testing in the dairy industry; and explain
microbes of significance to the New Zealand dairy industry.
Classification
Dairy Manufacturing > Dairy Product Safety and Risk
Management
Available grade
Achieved
Explanatory notes
Definition
Legislative requirements – refer to legislation and regulations that include but are not
limited to – Animal Products Act 1999, Animal Products (Dairy) Regulations 2005,
relevant Dairy Specifications/Notices.
Outcomes and evidence requirements
This unit standard is
Explain the three main types of microbes of importance to the dairy industry.
expiring
Outcome 1
Evidence requirements
1.1
Bacteria are explained in terms of general morphological features and
reproduction.
Range
1.2
shape, size, cellular structure, motility, endospores, binary fission,
bacterial growth curves.
Fungi are explained in terms of morphology and reproduction.
Range
yeasts include but are not limited to – size, cellular structure,
budding, binary fission, ascospores;
moulds include but are not limited to – size, mycelia structure,
fragmentation, conidia, spores.
New Zealand Industry Training Organisation
SSB Code 4827
 New Zealand Qualifications Authority 2016
NZQA Expiring unit standard
1.3
4827 version 6
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Bacteriophages are explained in terms of structure, reproduction, and control of
growth.
Range
size, virion morphology, lytic life cycle, lysogenic life cycle, control
of phage in the dairy industry.
Outcome 2
Explain factors affecting microbial growth and the use of these factors to control microbial
growth.
Evidence requirements
2.1
Nutrition of microbes is explained in terms of extracellular microbial enzymes
and by-products of microbial growth.
Range
2.2
lipolysis, proteolysis, fermentation, toxin production.
The effects of temperature on microbes is explained in terms of growth ranges,
microbial classification by growth range, and effects of heat and cold on
microbes in food.
Range
psychrophiles, psychrotrophs, mesophiles, thermophiles.
2.3
The water activity scale, water activity growth ranges, and effect of osmotic
pressure on microbes are explained in terms of effects on microbial growth.
2.4
The pH ranges are explained in terms of effects on microbial growth.
2.5
The classification of microbes by oxygen requirement is identified.
includes but is not limited to – aerobes, microaerophiles,
anaerobes, facultative anaerobes.
This unit standard is
Outcome 3
expiring
Explain the microbiological control of dairy products.
Range
Evidence requirements
3.1
The elimination of nutrients in dairy processing is explained in terms of process
plant cleaning, and the design and maintenance of processing facilities.
3.2
The use of temperature to control microbes is explained in terms of resistance
of vegetative cells, spores, and thermophilic biofilms to heat and cold.
Range
3.3
includes but is not limited to – pasteurisation, thermalisation, ultrahigh temperature processing, refrigeration, freezing.
The use of decreased water availability is explained in terms of sugared and
dried foods.
New Zealand Industry Training Organisation
SSB Code 4827
 New Zealand Qualifications Authority 2016
NZQA Expiring unit standard
Range
3.4
includes but is not limited to – sweetened condensed milks,
casein, powdered dairy products.
The use of decreased pH to preserve dairy product is explained in terms of
cultured products.
Range
3.5
4827 version 6
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cheese, fresh cultured products.
The elimination of oxygen as a means to control microbial growth is explained in
terms of vacuum packaging and canned products.
Range
cheese, canned, UHT products.
Outcome 4
Explain routine microbiological testing in the dairy industry.
Evidence requirements
4.1
Classification of microbes is explained in terms of genera and species.
4.2
Microbiological testing of dairy products is explained in terms of general
laboratory enumeration and isolation techniques.
4.3
Microbiological testing of the dairy process environment is explained in terms of
general laboratory techniques.
Range
includes but is not limited to – swabs, air, water.
Outcome 5
This unit standard is
Pathogenic bacteria of importance
in the New Zealand dairy industry are
expiring
explained in terms of growth characteristics, target populations, type of illness,
Explain microbes of significance to the New Zealand dairy industry.
Evidence requirements
5.1
infective dose, mortality rates, sources, and basic testing characteristics.
Range
5.2
includes but is not limited to – salmonella, listeria, Escherichia coli,
staphylococcus aureus, bacillus cereus, clostridium perfringens,
enterobacter sakazakii, campylobacter jejuni, yersinia
enterocolitica.
Spoilage organisms of importance to the New Zealand dairy industry are
explained in terms of growth characteristics, types of spoilage, control methods,
susceptible products, and basic testing characteristics.
Range
includes but is not limited to – yeasts and moulds, pseudomonas,
thermodurics, sulphite reducing clostridia, spore-formers.
New Zealand Industry Training Organisation
SSB Code 4827
 New Zealand Qualifications Authority 2016
NZQA Expiring unit standard
5.3
Indicator organisms of importance to the New Zealand dairy industry are
explained in terms of growth characteristics, control methods, and basic testing
characteristics.
Range
5.4
4827 version 6
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coliforms, enterobacteriaceae, enterococci, erobic plate count,
thermophiles.
Beneficial microbes of importance to the New Zealand dairy industry are
explained in terms of the effects of their growth on dairy products.
includes but is not limited to – starter bacteria, cheese moulds.
Range
Replacement information
This unit standard was replaced by unit standard 28981.
This unit standard is expiring. Assessment against the standard must take place by
the last date for assessment set out below.
Status information and last date for assessment for superseded versions
Process
Version Date
Last Date for Assessment
Registration
1
22 June 1995
31 December 2017
Review
2
5 July 1999
31 December 2017
Review
3
26 August 2002
31 December 2017
Revision
4
13 June 2003
31 December 2017
Rollover and
Revision
5
17 July 2009
31 December 2017
This unit standard is
Consent and Moderation Requirements (CMR) reference
0022
This CMR can be accessed at http://www.nzqa.govt.nz/framework/search/index.do.
expiring
Review
6
18 June 2015
31 December 2017
Please note
Providers must be granted consent to assess against standards (accredited) by NZQA,
before they can report credits from assessment against unit standards or deliver courses
of study leading to that assessment.
Industry Training Organisations must be granted consent to assess against standards by
NZQA before they can register credits from assessment against unit standards.
Providers and Industry Training Organisations, which have been granted consent and
which are assessing against unit standards must engage with the moderation system that
applies to those standards.
Requirements for consent to assess and an outline of the moderation system that applies
to this standard are outlined in the Consent and Moderation Requirements (CMR). The
CMR also includes useful information about special requirements for organisations wishing
New Zealand Industry Training Organisation
SSB Code 4827
 New Zealand Qualifications Authority 2016
NZQA Expiring unit standard
4827 version 6
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to develop education and training programmes, such as minimum qualifications for tutors
and assessors, and special resource requirements.
This unit standard is
expiring
New Zealand Industry Training Organisation
SSB Code 4827
 New Zealand Qualifications Authority 2016