Clarifications on the interpretation of technical issues about the Scientific Opinion on a summary of scientific studies undertaken by the UK Food Standards Agency (FSA) to support a proposed production method for smoked “skin-on” sheep meat

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EFSA Journal 2012;10(10):2937
Suggested citation: European Food Safety Authority; Clarifications on the interpretation of technical issues about the
Scientific Opinion on a summary of scientific studies undertaken by the UK Food Standards Agency (FSA) to support a
proposed production method for smoked “skin-on” sheep meat. EFSA Journal 2012;10(10):2937. [13 pp.]
doi:10.2903/j.efsa.2012.2937. Available online: www.efsa.europa.eu/efsajournal
© European Food Safety Authority, 2012
SCIENTIFIC REPORT OF EFSA
Clarifications on the interpretation of technical issues about the Scientific
Opinion on a summary of scientific studies undertaken by the UK Food
Standards Agency (FSA) to support a proposed production method for
smoked “skin-on” sheep meat1
European Food Safety Authority2, 3
European Food Safety Authority (EFSA), Parma, Italy
SUMMARY
In June 2011 the EFSA Panel on Biological Hazards (BIOHAZ) and the Panel on Contaminants in the
food chain (CONTAM) published a scientific opinion about the scientific validity of the studies
submitted by the FSA on the safety of burnt skin-on sheep meat. It was concluded that the hazard
identification presented in the studies submitted by FSA did not cover all potential biological and
chemical hazards and the studies were considered insufficient to conclude that the burnt fleece skin-on
sheep carcasses were suitable for human consumption and provide the same safety level as
conventionally produced skin-off carcasses. In June 2012 FSA requested EFSA to provide
clarifications about this scientific opinion on a number of issues i) the effect of the process on
vegetative microbiological pathogens, ii) the method of sampling for microbiological examination, iii)
the increased risk from bacterial spores, iv) the adequacy of control treatments, v) the production
standards of wool length and cleanliness of animals; and vi) dioxins, PCBs (Polychlorinated
Biphenyls), PAHs (Polycyclic Aromatic Hydrocarbons), PAHs and heterocyclic amines. The intention
of FSA is to produce a protocol for future studies based on the EFSA recommendations. The present
scientific report contains the reply by EFSA to the requests received by FSA.
Firstly FSA requested for guidance about the evaluation of the effects of the process on vegetative
pathogens. EFSA replies that, in order to assess the product safety, the hazard profile and the food
safety goals should be defined and a setting of pathogen-related targets for chilled carcasses has to be
considered. EFSA recommends that the type and number of samples to be tested should be
representative enough and adequate in number to cover the potential variability in the distribution of
the microbial hazards on the surface of the carcass before and after singeing.
Concerning the method of sampling, the standard sampling techniques are approved only for skinned
carcasses, so this cannot be used on burnt fleece skin-on carcasses for process hygiene assessment nor
for microbiological safety assessment.
1 On request from Food Standard Agency, Question No EFSA-Q-2012-00720, approved on 10 October 2012.
2 Correspondence: biohaz@efsa.europa.eu
3 Acknowledgement: EFSA wishes to thank Declan Bolton, Sava Buncic, Peter Fürst, Laurentius Ron Hoogenboom and
John Sofos for peer-reviewing this scientific output.

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FSA asked clarifications about the possible increased risk from spores for skin-on carcasses compared
to skin-off carcasses. The identification of spore and sporeforming bacteria as possible hazards should
be justified and, if these hazards were included, this should be supported by a proper risk assessment.
EFSA underlined that the safety of “burnt skin-on” sheep carcasses should be addressed compared to
“conventional skin-off” sheep carcasses within the same category of animals, including age. This
implies that adequate controls and treated samples have to be included in all experiments, so that the
results of the study can be statistically assessed.
FSA further asked clarifications about the EFSA conclusion that it would not be possible to achieve a
standard of “clipped, clean and dry” for animals that will be processed into skin-on sheep. It was
stressed by EFSA that the variability of fleece conditions was not explored and assessed or not
explained properly. It is recommended to include these aspects if further studies are undertaken on this
subject. The fleece status should have been identified as Critical Control Point (CCP), indicating clear
critical limits, monitoring procedures and corrective actions.
With regard to chemical hazards, the FSA sought further clarifications in relation to dioxins and PCBs,
PAH and Heterocyclic amines. EFSA stated that analyses for dioxins would be useful to give an
indication of their potential formation during the singeing process and moreover, it was are
recommended to normalize the samples concerning skin to muscle meat ratio for a better comparison
of results. EFSA wanted to stress that no recommendation was provided to perform analyses for PCBs.
EFSA concluded that the differences in the PAH concentrations from the FSA study in potentially
hazardous chemicals is rather limited and that the differences in the PAH concentrations indicate a
considerable variability in the process. It was recommended further standardized analyses which
should be normalized concerning skin to muscle meat ratio.
As temperature up to more than 500°C could be reached during the singeing and toasting process
using a hand-burner, local overheating may result potentially affecting not only skin surfaces but also
some inner tissues of the carcass, particularly in the cut/split areas. The local overheating of meat
directly exposed to the torch may generate heterocyclic amines. EFSA concluded that analyses for
these carcinogenic compounds would be useful at least to give an indication of their potential
formation.
© European Food Safety Authority, 2012
KEY WORDS
Burnt skin-on sheep meat, safety, hygiene, contaminants

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TABLE OF CONTENTS
Summary .................................................................................................................................................. 1
Table of contents ...................................................................................................................................... 3
Background .............................................................................................................................................. 4
Terms of reference.................................................................................................................................... 4
Assessment ............................................................................................................................................... 5
1. Introduction ..................................................................................................................................... 5
2. The effect of the process on vegetative microbiological pathogens ................................................ 5
3. Method of sampling for microbiological examination .................................................................... 7
4. The increased risk from bacterial spores ......................................................................................... 8
5. The adequacy of control treatments ................................................................................................. 9
6. The production standards of wool length and cleanliness of animals ........................................... 10
7. Dioxins and PCBs .......................................................................................................................... 10
8. PAHs .............................................................................................................................................. 11
9. Heterocyclic amines ...................................................................................................................... 12
References .............................................................................................................................................. 13

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BACKGROUND
The specific hygiene rules for food of animal origin require the complete skinning of the carcase and
other parts of sheep intended for human consumption, except for heads and feet (Section I, Chapter
IV, paragraph 8 of Annex III of Regulation (EC) No 853/2004). In the United Kingdom (UK) there is
a market for sheep carcases from which the skin has not been removed, to meet demand from certain
ethnic groups. Such carcases are commonly called “smokies”, as their production involves singeing or
burning the fleece. The UK Food Standards Agency (FSA) has carried out scientific studies to explore
the potential for the safe production of this product. In their summary report (FSA, 2010), compiled in
2010, the FSA concluded that “skin-on” sheep meat could be safely and hygienically produced in
approved slaughterhouses. In October 2010 the European Commission asked EFSA to issue a
Scientific Opinion on the FSA summary of scientific studies to support a proposed production method
for burnt “skin-on” sheep meat.
As a follow up of this request, the Panel on Biological Hazards (BIOHAZ) and the Panel on
Contaminants in the food chain (CONTAM) were specifically requested to provide a scientific opinion
about the scientific validity of the studies submitted by the FSA and on the relevance of their outcome
and conclusions for concluding on the safety of burnt skin-on sheep meat. Furthermore, the Panels
were asked to indicate if any additional public health hazards and the subsequent risks not
contemplated in the FSA studies needed to be taken into account before considering this burnt “skin-
on” sheep meat as safe. The scientific opinion was published on 15 June 2011 (EFSA, 2011). In this
opinion it was concluded that the hazard identification presented in the studies submitted by FSA did
not cover all potential biological and chemical hazards and information on their fate during the
process. Overall, the studies were considered insufficient to conclude that the burnt fleece skin-on
sheep carcasses produced by the method described were suitable for human consumption. Moreover,
the evidence submitted did not allow concluding that the hygienic condition, the microbiological
quality and the levels of harmful smoke-derived chemicals were similar to conventionally produced
skin-off carcasses.
TERMS OF REFERENCE
EFSA requests the BIOHAZ Unit to draft a scientific report including inputs from the CONTAM Unit
to clarify the requests by FSA as reported in the Annex of the letter received on 22 June about:
the effect of the process on vegetative microbiological pathogens;
the method of sampling for microbiological examination;
the increased risk from bacterial spores;
the adequacy of control treatments;
the production standards of wool length and cleanliness of animals; and
dioxins and PCBs, PAHs and heterocyclic amines.

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ASSESSMENT
1. Introduction
EFSA has received a letter from FSA where clarifications are requested on the interpretation of a
number of scientific and technical issues presented in the EFSA Opinion on a summary of scientific
studies undertaken by the UK Food Standards Agency to support a proposed production method for
burnt “skin-on” sheep meat (EFSA Panel on Biological Hazards (BIOHAZ) and Panel on
Contaminants in the Food Chain (CONTAM), 2011), from now on referred to as the “EFSA Opinion”
in this report.
As indicated in the letter, FSA aims to identify what further data are required to enable a full
assessment of the process for safe production of skin-on sheep carcases. Moreover, FSA is planning to
produce a protocol for future studies based on the EFSA recommendations and to request the Panels‟
opinion about the protocol before proceeding.
The BIOHAZ and CONTAM Units of EFSA have drafted the reply to the questions from FSA in the
form of the present scientific report that has been peer-reviewed by experts.
2. The effect of the process on vegetative microbiological pathogens
As indicated in the Annex to the letter received from FSA on 22 June 2012:
Guidance on how to practically evaluate the effects of the process on vegetative pathogens.
In order to demonstrate the safety of the product under study compared to the traditional product,
what would be the Biohazard Panel‟s advice in terms of the type and number of samples to be tested,
the time span of the testing and the pathogens to be included?
The studies included analysis for Enterobacteriaceae as an indicator of pathogens. This decision was
based on the number of sheep that were practical to process into skin-off sheep by the research
abattoir facilities available. We accept that results of testing for Enterobacteriaceae will not correlate
precisely with results for Salmonella spp. when present. However, testing for an indicator organism
to generate information for process hygiene assessment in situations where pathogen prevalence is
low is an accepted microbiological approach and is indeed noted in the recently published EFSA
Scientific Opinion on the public health hazards to be covered by inspection of meat (swine) (EFSA
Journal 2011; 9(9):2351) and EFSA report “Technical specifications on harmonised epidemiological
indicators for public health hazards to be covered by meat inspection of swine” (EFSA Journal
(2011);9(10) 2371). The relevant text from the report is reproduced below;
“There is a general recognition in the scientific literature that indicator microorganisms are much
better suited for use in process hygiene assessment than pathogenic microorganisms (Koutsoumanis
and Sofos 2004, Blagojevic et al;2011). This is due to the facts that pathogens occur in animals /on
carcasses relatively rarely.”
When pathogens occur naturally at a low prevalence, testing a practical number of control and
experimental samples is unlikely to produce data that will allow the risk to be assessed. An alternative
experimental approach is to artificially contaminate a relatively small number of samples with a high
level of pathogens that have been cultured in a laboratory. However, when this approach is used it
can be open to criticism as the contamination is not seen to represent what would occur naturally.
EFSA response:
In order to demonstrate the safety of the product under study, compared to the traditional product, the
type and number of samples to be tested should be derived from carcasses treated by a standardised
processing singeing method, which is not available at the moment. In fact, in the trials presented by

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FSA a custom made system was used in initial studies and a gas torch in the abattoir trial. No
production method was validated and no validated SOPs or HACCP guidelines were developed.
Without this, it is not possible to establish parameters, targets or limits that could be used in HACCP
plans and SOPs, including microbiological criteria and sampling locations, sample sizes, and types of
analyses to be performed.
In the EFSA Opinion it is stated that samples were tested only for indicator microorganisms. Although
it is agreed that TVC and Enterobacteriaceae are commonly acceptable indicators of processing
hygiene performance, they are not necessarily used as indicators of pathogen presence or absence
including spore-forming pathogens on burnt skin-on carcasses.
The EFSA Scientific Opinion and Report on swine meat inspection refer to testing for indicator
organisms for process hygiene assessment, but they refer to conventionally produced, and not burned
hair, carcasses.
The EFSA Opinion acknowledges that the choice of the indicators provides information on the process
hygiene, but also states:
“low TVC and Enterobacteriaceae counts on burnt fleece skin-on carcasses (or lower than on
conventional skin-off carcasses) do not necessarily correlate with absence of pathogens or
product safety. There was no microbial profiling of the carcass before and after the different
steps of the process”.
“the FSA studies conducted did not determine whether the capacity of the developed burnt
fleece skin-on sheep carcass production process to deal with microbiological hazards is similar
to that of the conventional skin-off sheep carcass production process, since effects on
pathogens were not evaluated”.
There is a difference between process hygiene assessment, where indicator organisms could be
reasonably used, and product safety assessment/process risk reduction assessment where the hazard
profile and the food safety goals should be defined. In the EFSA Scientific Opinion on the public
health hazards to be covered by inspection of meat (swine), the use of indicator organisms was
advocated for the purpose of process hygiene assessment only, not for the purpose of presence/absence
of pathogens on carcasses i.e. not for meat safety assessment. For the latter, a setting of pathogen-
related targets for chilled carcasses was suggested. The EFSA Opinion on burnt fleece skin-on sheep
meat considered that the FSA studies did not cover product safety assessment/process risk reduction
assessment, which would contribute to the assessment of the safety of burnt fleece skin-on sheep meat
and of its production process.
The type and number of samples to be tested should be representative enough and adequate in number
to cover the potential variability in the distribution of the microbial hazards on the surface of the
carcass before and after singeing taking into account the influence of:
the different climatological conditions and seasonality throughout the year during which
slaughtering is performed.
the status of the fleece (wet, dry, cleanliness and length of fleece);
the thermal process applied (temperature, time of application, carcass surface covered).
Experimental-model based studies including artificial inoculation of carcasses intended for the
production of burnt fleece skin-on sheep carcasses with non pathogenic surrogate strains of selected
pathogens, when available, represent a practical way to preliminarily assess the pathogen-reduction
effect achieved by the proposed production method. Again, the numbers processed and tested should
be adequate to provide statistical validity.

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Future studies should also provide a microbial risk assessment of the individual steps of shearing,
singeing, washing and toasting on the distribution and levels of bacterial contamination. If animals are
to be initially sheared or clipped as part of the procedural SOPs then an assessment of potential
airborne cross-contamination arising from this process should also be included. The same applies if
burnt wool deposits are to be removed by power-hosing. The potential cross-contamination arising
from bacterial aerosols and the potential risks associated with driving bacteria deeper into the carcass
tissue should be assessed.
Should the results be used for a global purpose including a far-reaching change of legislation and
wherever possible, experimental findings need to be validated under commercial, real-life situation.
3. Method of sampling for microbiological examination
As indicated in the Annex to the letter received from FSA on 22 June 2012:
To clarify whether the comments made in the Opinion (6th bullet of 3.2.2) on the inadequacy
of the microbiological sampling techniques used also apply to the enumeration of indicator
organisms.
The techniques applied were those laid down in relevant EU legislation.
The research undertaken by the University of Bristol4 used carcass sampling techniques based on
those that were laid down in the EU legislation that was in force at the time the experiments were
carried out, that is:
pre 2006 Decision 2001/471EC
post 2006 EU Regulation 2073/2005.
In addition, the ISO standard 17064/2003 was taken into consideration and 2 extra sites were
included to cover the different types of processing.
Excision samples were used because there is evidence to show that this approach will recover more
indicator bacteria than a surface swabbing technique (EFSA journal 2010 VOL 8 1452, Hutchinson et
al 2005 Journal of Food Protection, 68, 2155-2162). This was confirmed by the results from the small
abattoir study when both swabbing and excision techniques were used.
If analysis for Salmonella spp. had been included we would have used a surface swabbing method as
detailed in EU Regulation 2073/2005.
EFSA response:
According to EU legislation 853/2004 (Annex III, Chapter IV), the approved slaughtering process of
ovine and caprine animals foresees the complete skinning of carcasses and other parts of the body
intended for human consumption, excluding the head and feet.
It is stated in the EFSA Opinion that:
“the size (dimensions or weight) of the samples analysed microbiologically was not sufficient
for safety evaluation of burnt fleece skin-on carcasses. The processes of singeing, washing,
etc. may have altered the sites that could harbour increased contamination on a carcass”.
4 EFSA Scientific Opinion: Report Ref. Project Code MO1027 on “a practical investigation into the hygienic production of
“skin-on” sheep carcasses and cattle and sheep feet”

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“there was no assessment of injured cells or consideration of the effects of charred materials
on the cultivability of bacteria present using standard ISO methodologies. The potential
bacteriostatic effect of chemicals produced as a result of the fleece burning process on the
bacterial counts obtained using standard ISO methodologies was not considered”.
The referred ISO standard sampling techniques are designed, intended and approved to be applied to
skinned carcasses. Thus, without prior validation, they can neither be directly used on burnt fleece
skin-on carcasses for process hygiene assessment nor for microbiological safety assessment of burnt
fleece skin-on carcasses and of its process, because the microbial survival dynamics may be different
than in conventionally skinned carcasses.
Furthermore, the referred carcass sampling technique, according to the current EU legislation (Reg.
(EC) 2073/2005), is to be used for the purpose of process hygiene assessment (i.e. for small ruminant
carcasses, the regulation provides only for process hygiene criteria). The legislation does not state its
use for meat safety assessment, i.e. it does not provide food safety criteria for small ruminant
carcasses. For the latter purpose and as it was meant in the FSA studies, based on scientific arguments,
the technique would have to be adapted so to maximize the chances of detecting/isolating pathogens if
present on the carcass at final stage of slaughtering.
Taking into account these considerations, other sampling techniques should be explored and validated
in order to:
cover an adequately representative area of the carcass, and
account for the potential effect of the process in the survival dynamics of various types of
pathogens, specifically, in the absence of temperature data for the entirety of the carcass, the
microbiological assessment must take the potential for „cold spots‟ into account when
assessing bacteria survival.
4. The increased risk from bacterial spores
As indicated in the Annex to the letter received from FSA on 22 June 2012:
Further explanation of the comments relating to the increased risk from spores for skin-on
carcasses compared to skin-off carcasses.
In order to demonstrate the safety of the product under study compared to the traditional product,
what would be the Biohazard Panel‟s advice in terms of the type and number of samples to be tested?
The Opinion noted that the hazard identification should have included spore-forming pathogenic
bacteria (species of Clostridium and Bacillus). We have noted that spores were not identified as a
hazard in the recent Opinion on public health hazards to be covered by inspection of meat (swine)
2011.
The fleece is the source of spore-forming bacteria and we agree that when pelts are removed there is a
possibility that spore-forming bacteria can be transferred from the fleece to the skin-off carcasses.
However, for skin-on carcasses the clipped fleece is removed by burning at a temperature that would
destroy any bacterial spores on the fleece or skin.
Both skin-on and skin-off carcasses can be contaminated with spores during the dressing procedure
and hygienic procedures based on HACCP principles should be in place in all approved
slaughterhouses, to control air movements from the lairage into the dressing area of the
slaughterhouse. Clipping could mobilise spores into the air which could lead to contamination of
carcasses but if clipping is carried out at the slaughterhouse this could be for both skin-on and skin-
off production and it would be the responsibility of the FBO to undertake the procedure in a hygienic
manner with audit by the OV. We also envisage that for the skin-on process the sheep are most likely

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to be clipped on-farm shortly before transport to the slaughterhouse, as this may be preferable from a
welfare aspect and also the slaughterhouse may charge the producer for clipping.
The Opinion suggested that there may be a risk of survival of spore-forming bacteria on cold spots
during fleece removal by burning. As the production specifications require the removal of the clipped
fleece by burning it is not possible to have cold spots, as if the fleece does not burn it is not able to be
removed.
EFSA response:
Sporeforming bacteria were not included by FSA in the hazard identification of burnt fleece skin-on
sheep carcasses. In the FSA studies explanations supported by adequate evidence were not provided
about the reason why these hazards are not included. On the contrary, if spores and sporeforming
bacteria had been considered in the hazards list, in that case a proper risk assessment for these hazards
should have been performed.
Beyond this issue regarding the relevance of spores and sporeforming bacteria as hazards, it is stated
by FSA that the temperature reached on the skin surface treated with the custom made singeing rig
was “reasonably” uniform at 70-85°C. If proved that this temperature is reached throughout the whole
skin surface (it is stated that no attempt was made to control the temperature), and that no
“temperature-safe pockets” are present on the skin, where spores can be protected by thermal
inactivation, it would be still not enough to inactivate bacterial spores. The recent EFSA opinion on
meat inspection on swine only applies to conventionally processed swine carcasses, which cannot be
compared for hazard analysis of burnt fleece skin-on sheep carcasses.
5. The adequacy of control treatments
As indicated in the Annex to the letter received from FSA on 22 June 2012:
To clarify the conclusion in the Opinion that the FSA studies “often lacked adequate control
treatments”.
Section 3.2.2 bullet point 5 questions the adequacy of control treatments. In the FSA summary only the
small abattoir trial did not include skin-off controls and an explanation was provided. It would be
helpful if more detail could be provided on any issues with the controls identified by the Panels in the
other studies undertaken.
EFSA response:
In the EFSA Opinion it was stated that “the basis of the determination of the number of carcasses
processed and of the number of samples tested in the FSA studies, especially those that compared the
microbiological status of burnt fleece skin-on and conventional skin-off carcasses, was not explained.
The numbers of carcasses processed and samples tested may not be adequate to cover variability and
determine statistical significance of the results. Experimental design of FSA studies presented often
lack adequate control treatments. For example, the commercial abattoir trial involved only six
animals, without skin-off controls. Lack of study repetition and replication does not allow inferences
for other conditions or variability in parameters during skin-on carcass production”.
It was clearly stated at the beginning of the EFSA Opinion under the clarification of terms of reference
that the safety of “burnt skin-on” sheep carcasses is addressed compared to “conventional skin-off”
sheep carcasses within the same category of animals, including age. This is necessary because the FSA
study is ultimately aimed at providing a basis for change of legislation that would allow introduction
of a new production system. In such cases, it would be necessary to know whether the new production
system (i.e. of burnt skin-on sheep carcasses) ensures the same, better or worse level of consumer
protection compared to existing production system (i.e. conventional skin-off sheep carcasses).

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By keeping adequate control and treated samples in all experiments, the results of the study can be
statistically assessed.
6. The production standards of wool length and cleanliness of animals
As indicated in the Annex to the letter received from FSA on 22 June 2012:
Further clarification on why the Opinion concluded that it would not be possible to achieve a
food business operator, and competent authority audited, standard of “clipped, clean and
dry” for animals that will be processed into skin-on sheep.
The Opinion expresses concerns about the cleanliness of the sheep on several occasions. This was also
a concern for the FSA and was why the proposed specification states animals to be processed into
skin-on carcasses to be first clipped and then kept clean and dry until processing. This would be a
control for the food business operator and would be audited by the competent authority. Animals not
in this condition would be unable to be processed. The Opinion seems to suggest that this standard
would not be possible to meet and that for this reason we should have undertaken studies to show what
happens if “dirty” sheep were processed. The hygiene legislation requires animals to be clean
enough at slaughter to avoid unacceptable contamination of the meat during slaughter and we felt that
the risk management standard we are proposing is in line with this requirement.
EFSA response:
The EFSA Opinion concluded that “the condition of the animals (clean and dry) used in all FSA
studies represented a “best case scenario”, while a “worst case scenario” was not assessed (e.g.
variability in season, animal cleanliness, age, breed, fleece length, condition and thickness). A range of
fleece conditions, as in normal slaughtering situations, could have been included in the FSA study to
assess this variability. Thus, based on those findings, the report would have included the Critical
Control Point (CCP) related to fleece status, indicating clear critical limits, monitoring procedures and
corrective actions.
Furthermore, as reported in the EFSA Opinion, the role of shearing/clipping wool in the generation of
bacterial aerosols leading to air-borne cross-contamination, animal to animal and other cross-
contamination via shearing equipment and hands, and cross-contamination of the final product was not
taken into account in the FSA studies (see also Section 2 of this Report).
In general, variability was not explored or, if explored, it was not explained properly. It could be
recommended to include these aspects if further studies are undertaken on this subject.
7. Dioxins and PCBs
As indicated in the Annex to the letter received from FSA on 22 June 2012:
Further comments on the points made below regarding the discussion in the Opinion on
Dioxins and PCBs.
The Opinion refers (section 5.1.1) to the lanolin content of wool and the possibility that it will absorb
lipophilic contaminants from the atmosphere (heavy metals are mentioned, but these are not generally
considered to be lipophilic). No supporting evidence for such an effect is cited and all but a thin layer
(3-5mm) of the wool is removed before treatment.
The possibility of adhering soil particles is also raised, especially when the sheep are grazed in areas
prone to flooding. The FSA is aware of the associated risks, having funded substantial research into
the impact of livestock farming in flood-prone areas on contaminant levels in food (see Lake et al.,
Env Sci Tech 2005, 39:23, 9033, with a further 5-year project is almost complete). As above, any risk

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would be minimised by the removal of most of the wool before treatment and the fact that the animals
must subsequently be kept clean, as discussed in point 5.
Dioxin and PCB levels in sheep meat are already regulated through contaminants legislation and we
do not expect the treatment to increase the dioxin level.
EFSA response:
The protocol to produce burnt fleece skin-on meat is very well described in the FSA studies. These
procedures can be considered as best case scenarios. Animal related parameters, such as breed,
thickness, length of wool and animal cleanliness were not considered. According to the reports of the
FSA studies, the temperature during the defleecing singe reaches 515°C at incandescent glowing
sections of fleece directly under the burner and around 70-85°C on the carcass surface. The singeing
process is performed with a hand-burner at a distance of around 0.5 m. Depending on the location,
individual parts of the fleece need to be scorched for a longer or shorter time. It can not be excluded
that dioxins are formed at temperatures around 515°C, especially in the presence of organic material,
such as wool. Therefore, EFSA stated that analyses for dioxins would be useful to give an indication
of their potential formation under the chosen parameters. In this respect, it is recommended to
normalize the samples concerning skin to muscle meat ratio for a better comparison of results. EFSA
wants to stress that it did not recommend performing analyses for PCBs.
8. PAHs
As indicated in the Annex to the letter received from FSA on 22 June 2012:
Clarification on what additional evidence would be required to demonstrate that PAH levels
are acceptable.
The data generated in the abattoir trial shows a PAH profile that is characteristic of direct hot-
smoked meat. Although there is some minor variability in the data, with the exception of two outliers
for benz(a)anthracene, the results are generally very consistent and all would comply not only with the
existing limit for benzo(a)pyrene in smoked meat and the new limit for the sum of benzo(a)pyrene,
benz(a)anthracene, benzo(b)fluoranthene and chrysene but also with the revised lower limits that will
come into force in 2014. Having demonstrated that this is readily achievable, it would be for the food
businesses concerned to ensure compliance taking into account process variables.
The revised PAH regulations will include an additional category of „heat-treated meat and heat-
treated meat products intended for the final consumer‟. This is intended to provide a means to enforce
PAH limits on meat/meat products that have undergone a heat treatment resulting in formation of
PAH but which do not fit the normal definition of smoked meat. Skin-on sheep meat could be covered
by this category but we suggest it would be more appropriate to consider it a smoked meat product for
which the tighter PAH limits will apply from 1 September 2014.
EFSA response:
The FSA study of potentially hazardous chemicals associated with burnt fleece skin-on sheep meat is
limited to the analysis of six samples from each of six sheep for 27 different PAHs, including the 16
priority compounds identified by EFSA. As pointed out correctly by FSA, all measured concentrations
for benzo[a]pyrene comply with the current maximum levels for smoked meat and meat products.
However, the sample with the highest level for PAH4 of 10.74 µg/kg almost reaches the maximum
level of 12.0 µg/kg proposed by the European Commission to be effective from 1.9.2014 onwards.
Moreover, two samples with elevated benz(a)anthracene concentrations from one carcass differed by
about 10-fold from the concentrations determined in the remaining samples from the same carcass. As
this PAH is normally not present at these high concentrations in fresh meat it must have been
introduced as a result of the singeing process and EFSA concluded that the differences in the PAH
concentrations indicate a considerable variability in the process which requires further standardized

Clarifications on technical issues about smoked skin-on sheep meat
EFSA Journal 2012;10(10):2937
12
analyses. As mentioned earlier for dioxins, future analyses for PAH should be normalized concerning
skin to muscle meat ratio for a better comparison of results.
9. Heterocyclic amines
As indicated in the Annex to the letter received from FSA on 22 June 2012:
Further explanation of why the issue of heterocyclic amines has been raised specifically in relation to
skin-on sheep meat but not in any other context. What specific evidence would be expected and on what
would a risk assessment be based?
Heterocyclic amines have not previously been raised as a risk to health in cooked meat products. The Opinion
states that „formation of heterocyclic amines can be reduced by avoiding direct exposure of meat to
temperatures higher than 150oC‟. In the production of skin-on sheep meat, the meat below the skin is not cooked
and retains the appearance of fresh meat after the skin has been burnt. During the process the skin will only
reach this temperature for a short time. Meat subjected to conventional cooking processes such as roasting,
grilling and frying generally reaches temperatures much higher than 150oC and often for a significantly longer
period of time.
EFSA response:
The singeing and toasting process using a hand-burner at temperatures up to more than 500°C is a
specific procedure not common in food production. As already mentioned, individual parts of the
carcass may need to be scorched for longer or shorter times, e.g. if there are areas of rough wool still
present on the animal after shearing. As a result, local overheating may result potentially affecting not
only skin surfaces but also some inner tissues of the carcass, particularly in the cut/split areas such as
the neck, the legs and along the median line where meat could be directly exposed to the torch. As
heterocyclic amines can be generated under these conditions, EFSA concluded that analyses for these
carcinogenic compounds would be useful at least to give an indication of their potential formation.

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EFSA Journal 2012;10(10):2937
13
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