NZQA registered unit standard
28607 version 1
Page 1 of 4
Title
Explain a wet and dry process for the production of casein and
caseinate in a dairy processing operation
Level
5
Credits
Purpose
20
This theory-based unit standard is for experienced people
carrying out milk product processing in a dairy processing
operation.
People credited with this unit standard are able to explain: the
wet and dry process for the production of casein products, and
explain the wet and dry process for the production of caseinate,
in a dairy processing operation.
Classification
Dairy Processing > Milk Products
Available grade
Achieved
Explanatory notes
Legislation
Legislation relevant to this unit standard includes but is not limited to the Animal Products
Act 1999, Health and Safety in Employment Act 1992, and Animal Products (Dairy)
Regulations 2005.
Outcomes and evidence requirements
Outcome 1
Explain the wet and dry process for the production of casein products in a dairy processing
operation.
Evidence requirements
1.1
The composition of whole milk for processing is explained in terms of the
influence on casein production.
Range
1.2
influences include but are not limited to – seasonal variations, form
of solution or dispersion, physical state and stability, trends in the
casein to fat ratio.
The casein fraction of milk is explained in terms of its physical micelle structure,
destabilisation and precipitation by acid and enzyme, and dissolving of acid
casein by alkoli.
Primary Industry Training Organisation
SSB Code 101558
 New Zealand Qualifications Authority 2016
NZQA registered unit standard
1.3
The principles of whole milk separation and pasteurisation are explained in
terms of their influences on casein and whey processing.
Range
1.4
principles include but are not limited to – complete precipitation,
curd uniformity, low fines in whey, minimum curd breakdown
during washing, non-sticky curd in the hot wash and during drying;
methods include but are not limited to – dewheying, washing,
dewatering, drying, dry processing.
The principles used in the production of rennet casein are explained in terms of
the methods used.
Range
1.8
principles include but are not limited to – lactic acid starter
selection and addition, casein coagulation, casein cooking,
acidulation of whey and curd, dewheying, casein curd washing,
casein curd dewatering, casein drying, cooling and tempering
casein, grinding and sieving casein, casein blending;
methods include but are not limited to – direct steam injection,
indirect cooking, combination cooking.
The principles used in the production of mineral acid casein are explained in
terms of the methods used.
Range
1.7
methods include but are not limited to – acid precipitation at the
isolelectric point of casein, proteolytic enzyme precipitation at
neutral pH, use of heat and alkoli treatment, resultant solubility of
the precipitates in sodium hydroxide.
The principles used in the production of lactic acid casein are explained in terms
of the methods used.
Range
1.6
influences include but are not limited to – skimming efficiencies,
market requirements, influences on fat content, microbiological
flora, control of lactic acid starter incubation.
The precipitation of casein and whey proteins from skim milk is explained in
terms of the methods used.
Range
1.5
28607 version 1
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principles include but are not limited to – kappa casein peptide
bond specificity, reaction rates for the enzymic and clotting stages,
casein concentration, enzyme concentration, temperature pH,
calcium ion concentration, heat treatment of the milk, disruption of
gel formation, rennet addition;
methods include but are not limited to – cold set, hot set, cooking.
The analysis and grading of casein is explained in terms of the basis of grading
specifications, testing methods and texting frequencies, and common reasons
why the casein may be out of specification.
Range
analyses and grading may include but is not limited to – moisture
content and homogeneity, protein, fat, acidity, pH, lactose, ash,
Primary Industry Training Organisation
SSB Code 101558
 New Zealand Qualifications Authority 2016
NZQA registered unit standard
28607 version 1
Page 3 of 4
solubility, colour, particle size, purity, Aerobic Plate Count (APC),
coliforms, E.coli, thermophiles, staphylococci, yeasts and moulds,
bacterial spores, trace elements, pesticides, inhibitory substances,
phosphatise, nitrates and nitrites, bulk density, sediment and
discolouration, appearance, flavour and odour, functional tests;
evidence is required of six analyses and grading specifications.
Outcome 2
Explain the wet and dry process for the production of caseinate in a dairy processing
operation.
Evidence requirements
2.1
The caseinate conversion reaction process is explained in terms of differences
between the ideal caseinate reaction and the commercial caseinate process.
Range
caseinate conversion reaction process includes but is not limited
to – particle size reduction, mixing of alkoli with the casein
suspension, high shear mixing after alkali addition, reaction
dissolving.
2.2
The sodium caseinate conversion process is explained in terms of chemical,
physical and microbiological requirements, factors that influence the rate of
dissolving and limitations on the total solids content at which sodium caseinate
solutions can be produced and spray dried.
2.3
The calcium caseinate conversion process is explained in terms of reasons,
requirements, critical steps, temperature, total solids and pH influences on
viscosity and gellation.
2.4
The total milk protein (TMP) conversion process is explained in terms of the
differences between acid casein conversion and the TMP process technique.
2.5
The process of atomisation and spray drying of soluble caseinate concentrate is
explained in terms of viscosity control and prevention of heat denaturation, the
purpose of atomisation, the process variables that affect the degree of
atomisation and the main stages involved.
2.6
The main components of a spray drier are explained in terms of their functions
and principles of operation.
Range
components include but are not limited to – atomisers, primary
drying chamber, secondary drying, powder air separation, cooling
and conveying, agglomeration and instantising.
2.7
The prevention of fire and explosions during spray drying is explained in terms
of operator responsibilities.
2.8
The analysis and grading of caseinate is explained in terms of the basis of
grading specifications, testing methods and testing frequencies, and common
reasons why the caseinate may be out of specification.
Primary Industry Training Organisation
SSB Code 101558
 New Zealand Qualifications Authority 2016
NZQA registered unit standard
28607 version 1
Page 4 of 4
analyses and grading may include but are not limited to – protein,
moisture, lactose, fat, ash, sodium, calcium, pH, trace metals,
nitrates and nitrites, pesticides, colour, sediment, rate of solution,
particle size, wettability, dustiness, flowability, dispersibility,
blendability, static electricity, hydration viscosity;
evidence is required of six analyses and grading specifications.
Range
Replacement information
Planned review date
This unit standard replaced unit standard 768 and unit
standard 8959.
31 December 2020
Status information and last date for assessment for superseded versions
Process
Version Date
Last Date for Assessment
Registration
1
18 June 2015
N/A
Consent and Moderation Requirements (CMR) reference
0022
This CMR can be accessed at http://www.nzqa.govt.nz/framework/search/index.do.
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
to develop education and training programmes, such as minimum qualifications for tutors
and assessors, and special resource requirements.
Comments on this unit standard
Please contact the Primary Industry Training Organisation standards@primaryito.ac.nz if
you wish to suggest changes to the content of this unit standard.
Primary Industry Training Organisation
SSB Code 101558
 New Zealand Qualifications Authority 2016