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Royal Society of Chemistry
Mastership in Chemical Analysis (MChemA)
Examiners’ report 2019
Jane White (Chief Examiner)
Liz Moran
Alastair Low
Megan McLean
Introduction
This is the annual report of the Examiners for the Mastership in Chemical Analysis for the
year ending 31 December 2019. These general comments are intended for candidates and
their counsellors, to help them understand the expectations of the examiners and to aid their
preparations for the MChemA.
The MChemA Regulations, Syllabus and Guidance Notes can be found on the RSC website
at http://rsc.li/mchema.
Part A
One candidate sat this paper achieving a pass mark. The candidate demonstrated an
acceptable range and depth of knowledge answering questions 2, 4-7 on topics of gas
chromatography, atomic spectroscopy, solid phase extraction, ELISA, Kjeldahl and Karl
Fisher titrations and data analysis. The questions were designed to probe basic
understanding of the underpinning theory of the techniques together with their applications
and results interpretation.
Part B
Two candidates sat the examination in October 2019; both candidates sat both papers. One
candidate had sat both Part B papers in 2018.
Paper B1
Of the eight questions set, two questions were not attempted by either of the candidates.
One question asked the candidates to detail the legislation relating to fruit juice and nectars.
The Fruit Juices and Fruit Nectars (England) Regulations 2013 define juices and nectar and
set specific standards that they should meet. However, reference should be made to other
relevant legislations such as the Contaminates in Foods (England) Regulations 2013 and EC
1881/2006 which sets limits for patulin in apple juice and ochratoxin A in grape juice.
The second part asking the candidates to explain how fruit juice drinks should be analysed.
The question is for a juice drink and as such is not covered by the juice and nectar
regulations. The candidates should discuss the issues associated with this type of product.
The second question related to how novel foods are authorised. The candidate should
reference The Novel Foods (England) Regulations 2018 (The Novel Foods (Scotland)
Regulations 2017) and (EU) 2015/2283 discussing the approve system in general and the
requirement for a food to be on the EU approved list prior to the food being placed on
the market.
The second part of the question asked what the status and requirements are for Chia seeds,
CBD oil, Geranium and Raspberry ketones.
Below is an example of the entry for Chia seeds from EU Novel food catalogue
The Commission Decision 2009/827/EC authorised the placing on the market of Chia (Salvia
hispanica) seeds as a novel food ingredient, to be used in bread products with a maximum
content of 5 % Chia (Salvia hispanica) seeds. The Commission Implementing Decision
2013/50/EU has authorised an extension of the use of Chia seed -no more than 10% -in
baked products, breakfast cereals, fruit nut and seed mixes, and the marketing of pre-
packed chia seeds. Additional labelling of pre-packaged Chia seeds is required to inform the
consumer that the daily intake is no more than 15 g/day. Chia seed as such may be sold to
the final consumer in a pre-packaged form only. The authorisation letter from Ireland (18
September 2015) has authorised an extension of the use of Chia seeds in fruit juices and
fruit juice blends. Chia (Salvia hispanica) is a summer annual herbaceous plant belonging to
the Labiatae Family. The species originated in mountainous areas extending from West
Central Mexico to Northern Guatemala. Chia seeds require sub-tropical conditions for their
growth.
A synopsis of the requirements for use should be given.
Question 1 asked candidates to discuss unregulated mycotoxins. In particular the methods
of analysis and how the results would be interpreted. EC 1881/2006 sets limits for certain
commodities and mycotoxins. The question was looking for candidates to discuss the
analysis for a range of mycotoxins and how the analyst would interpret results where no
limits are set. The candidate should have made reference to using EFSA recommendation,
WHO, Codex or other sources information sources. They may have discussed toxicity data
and conversion to daily acceptable levels. The second part of the question asked how you
would analyse for marine biotoxins and how the results would be interpreted. Although not
many labs are accredited for biotoxins, a Public Analyst should have an understanding of the
subject as they may subcontract samples for this analysis. An understanding of the different
types of biotoxins would be expected with a basic understanding of the methods of analysis.
Question 2a asked the candidates to identify the compositional standards for dairy product and explain the analysis required for official controls. The answers should address the compositional standards for all dairy products and should include reference to EC No
1234/2007, EC 835/2004, Code of practice on the compositional standards for cream
designation in the UK, Code of practice on the compositional standards for cheese designation in the UK and Code of practice on edible ices,
Question 2b asked how you would analysis for fat in different types of dairy products ie milk,
yogurt and cheese. The candidate should discuss the use of Gerber fat, Rose Gottlieb, Acid
hydrolysis method and the determination of milk fat from butyric acid content.
Question 4 asked the candidates to discuss the legislation, standards and analysis for 4
products:- Fresh tuna, whisky based liqueur, Steak and kidney pie and Cereal based snacks.
The candidates were expected to think passed the obvious and ideally be aware of ongoing
issues particularly with fresh tuna. OPSON has looked at the use of unpermitted additives in
tuna as well as histamine, freshness and speciation. The candidates were also require to
understand the definitions of a liqueur from the Spirit Drink Regulations 2008 (110/2008) and
definitions in The Products Containing Meat etc Regulations 2014. The cereal based snacks
required discussion around testing for GMO, nutritional analysis, health and nutritional
claims if were declared.
Question 5a asked the candidates to identify three foods which are not required to bear a
list of ingredients. The candidates should state that EU 1169/2011 Article 19 lists foods that
do not require an ingredients list. The foods that are exempt should be listed along with any
criteria that must be met to qualify for the exemption.
Question 5b asked candidates to state the specific provisions concerning the indication of
ingredients by descending order of weight for four categories of ingredient:
i. Added water and volatile products
ii. Mixtures of spices or herbs, where none significantly predominates
iii. Ingredients constituting less than 2% of the finished product
iv. Refined oils
The candidates should be aware of the requirements of Annex VII of 1169/2011 and how
they would affect the ingredients list
Question 5c asked the candidate to summarise the presentation requirements for the
mandatory particulars as prescribed by these Regulations. The candidate should make
reference to the requirements within 1169/2011 and any appropriate guidance documents.
Question 6a asked the candidate to outline the relevant legislation and guidance that covers the microbiological safety of food. The Microbiological Criteria Regulation 2073/2005 establishes microbiological criteria for certain micro-organisms and provides rules to be complied with by food business operators. The candidates should also reference HPA Guidance for Food Examiners and The safety and shelf-life
of vacuum and modified atmosphere packed chilled foods with respect to non-proteolytic Clostridium botulinum.
Question 6b
The candidate was asked what examinations would applied to Raw milk cheese, Rice based
food, vacuum packed food and a cooked sliced meat
Consideration should have been given to
EC2073/2005 end of manufacture
EC2073/2005 during shelf-life
HPA guidelines
Vacuum packed guidance.
Question 7 asked the candidate to give an outline of the relevant legislation which governs
the presence of acrylamide in food and to include in the answer its formation, health effects,
methods of analysis and ways of controlling acrylamide in one chosen product type.
In 2015 the Scientific Panel on Contaminants in the Food Chain (CONTAM) of the European
Food Safety Authority (‘the Authority’) adopted an opinion on acrylamide in food (4). Based
on animal studies, the Authority confirms previous evaluations that acrylamide in food
potentially increases the risk of developing cancer for consumers in all age groups. Since
acrylamide is present in a wide range of everyday foods, this concern applies to all
consumers but children are the most exposed age group on a body weight basis.
Regulation 2017/2158 establishes best practice, mitigation measures and benchmark
levels for the reduction of the presence of acrylamide in food. The regulations also give
the performance criteria required for methods of analysis.
Paper B2
Both candidates attempted paper B2. Only one question was not attempted and this was
question asked the candidates to discuss the method validation requirements for the
analysis of anions in potable waters using ion chromatography for 20 marks. Method
validation is an essential activity within any laboratory and ensuring methods are fit for
purpose an integral role of the Public Analyst. The principles of method validation include
ascertaining the level of interest from the client or in this case from legislation - The Water
Supply (Water Quality) Regulations 2016. Carrying out a literature search to determine what
methods maybe appropriate if one is not indicated in the legislation. Establishing
performance criteria from legislation if appropriate. Carrying out appropriate analysis of
spikes, certified reference material, blanks etc. in appropriate matrixes. Evaluation of
method/s against the performance criteria identified. The Drinking Water Inspectorate
indicates minimum requirements for replicates, spikes etc. Relevant guidance documents,
such as the Drinking water inspectorate guidance document and Accreditation Requirements
for Sampling and Testing in Accordance with the Drinking Water Testing Specification
(DWTS) should be referenced.
Question 1 (Policy) asked the candidates to discuss the current policy on the interpretation
of the results of food allergen analysis in light of recent food incidents and include your
opinion(s) on how allergen management and the presentation of information should be
developed in food preparation and service environments. Due to recent high profile incidents
there has been a number of consultations on current allergen labelling. The question
prompts candidates to discuss how results are interpreted including where current legislation
stipulates limits such as those for sulphur dioxide and gluten and the issues surrounding
interpretation were no legislative limit is give. Is VITAL an acceptable approach? Should
every food require an ingredient list? The candidate is asked to discuss the topic in a logic
and informed manner expressing a coherent argument for their options regarding the future
policies for allergen labelling.
Question 2 (Policy) asked the candidates to discuss the threat to food authenticity in a
worldwide food supply chain in relation to the FSA mission statement - “Our job is to use our
expertise and influence so that people can trust the food they buy and eat is safe and what it
says it is.” Our food comes from a worldwide market where food supply chains are varied
and sometime very complex. The threat to food authenticity may come from different
sources such as deliberate adulteration, cross contamination, differing legislative standards
etc. Whatever the cause consumers maybe disadvantage or worse still have their health
compromised. The question invites discussion of the issues associated with an extended
food chain. The candidate should explore the opportunities for adulteration, why it may occur
along with how adulteration may be detected and the solutions that could be used to mitigate
the issues such as the use of blockchain, DNA tracking or other possible solutions.
Question 3a (Agriculture) asked the candidate to outline one method of analysis for each
of the different forms of nitrogen in a fertiliser. The Fertilisers (Sampling and Analysis)
Regulations 1996 Schedule 2 sets out the methods of analysis to be used for fertilisers.
Methods for different types of nitrogen stipulated in the regulations should be outline
Question 3b (Agriculture) asked the candidate to discuss the preparation of different types
of solid fertiliser for analysis. . The Fertilisers (Sampling and Analysis) Regulations 1996
Schedule 2 outline how different types of fertilisers should be prepared. This includes what
samples should not be ground.
Question 4 (Agriculture) asked candidates to outline the main provisions of Regulation EC
767/2009 regarding the placing on the market and use of animal feeding stuffs for 20 marks.
A good working knowledge of Regulation (EC) No 767/2009 is essential for a future Agricultural Analyst. The candidate was expected to outline the main provisions of the legislation. The basic principle that feed should be safe and does not have a direct adverse effect on the environment or animal welfare is the fundamental. Furthermore it should be sound, genuine, unadulterated, fit for its purpose and of merchantable quality; and labelled, packaged and presented in accordance with the provisions laid down in this Regulation and other applicable Community legislation. The regulations outline the mandatory labelling requirements for feed material and compound feeds. These are covered in articles 15, 16, 17 and 18. Annex 1 to 6 should be outline including the technical provisions, prohibited materials, permitted tolerances required for nutritional declarations and the labelling requirements for additives.
Question 5a (Agriculture) asked the candidates to discuss the issues associated with the
onsite sampling of bulk feed, on farm mixes and mineral feeds. EC regulation No
152/2009 outlines the requirements for sampling. However the candidate would be expected
to discuss practical issues associated sampling as well as the requirements of the
regulations.
Question 5b (Agriculture) asked the candidate to discuss how you would assess the
quality of forage feed. The candidate should define a forage feed and the feed value it brings
as well as what affects it quality.
Question 6 asked candidates to outline the official methods of analysis for Phosphorus soluble in neutral ammonium citrate in a NPK fertiliser, Magnesium in a fertiliser, Starch in an animal feed,Oil in an animal feed and Claviceps purpurea in a feed material. The fertiliser methods are stipulated in The Fertilisers (Sampling and Analysis) Regulations 1996. The animal feeds methods are given in The Feed (Sampling and Analysis and Specified Undesirable Substances) (Scotland) Regulations 2010 enacting 152/2009. These regulations provide methods for a starch and oil in feeds. Claviceps purpurea The examination is performed in cereals. Quantification is performed by selecting and weighing of ergot and its fragments with a
particle size > 0,5 mm out of the test sample or an aliquot of it.
Question 8a asked the candidate what are the treatments permitted on natural mineral water. The Natural Mineral Water, Spring Water and Bottled Drinking Water (England) Regulations 2007 set out the treatments that are permitted on a natural mineral water.
Question 8b asked the candidates to discuss what indicator analytes may be used to
determine the source of water discovered in a residential basement? The candidates were
asked to include the challenges in interpreting the results. The answer should include a
discussion of the different types of water that may be present and their unique
characteristics. This would inform the analysis that is carried out to determine the source of
the water. However consideration has to be given to the material the water may have passed
through and how this would have affected the results.
.
Part C
One candidate sat the examination in 2019.
Question 1 was not completed by the candidate. The question asked the candidate to
interpret results obtained for the analysis of Melamine Bowls for Formaldehyde. The
candidate had to determine if the results of the replicates constituted a fail and report
appropriately.
Question 2 asked the candidate to write a certificate for a PK fertiliser 0-5-14 containing
magnesium. The results of analysis and declared values were given. The candidate had to
take into account the different permitted tolerance and determine if the name of the feed was
correct
Question 3 asked to candidate to write a certificate of analysis for a Pure Palm Oil. The oil
was found to contain Sudan 4 and salt.
Microscopy
Candidates are reminded that they should visually inspect the whole specimen prior to
commencing analysis. A written description of the material should be given. The object
should then be examined using a low powered microscope. Any distinctive features should
be noted. If the specimen is comprised of more than one material, the material should be
separated prior to examination under a high powered microscope. Candidates should label
the individual slides and produce labelled drawings of the distinguishing features found.
Question 4 asked the candidate to identify a material found in a jar of ‘Black bean cook-in
sauce‘. The material did not have any distinguishing features.
Question 5 asked the candidate to identify a material found in an unlabelled container within
a shop. They material was liquorice root.
Question 6 asked the candidate to identify unexplained material collecting on surfaces in a
house. The specimen was comprised of material produced from a carpet which had started
to degrade.
Interactive
Question 7 asked the candidate to examine a bagged sliced bread which had been sampled
following a complaint of an unusual taint. The candidate was asked to investigate the issue
and report their findings. The hot bread had been placed on new pine cooling boards and
the taint originated from the terpenes released from the wood.
Question 8 asked the candidates to investigate a report of an alleged illness has been
received from a member of the public after consumption of a vegetarian takeaway meal. The
meal comprised of a meat dish, dhal and rice. The dhal contained significant levels of
bacillus cereus.
J. White
Chief Examiner