Chemical
Hazard Evaluation POLYCYCLIC
AROMATIC HYDROCARBONS IN BARBECUED MEAT
July 2004
Food and Environmental Hygiene Department
The Government of the Hong Kong Special Administrative
Region
This is a publication of the Food
and Public Health Branch of the Food and Environmental
Hygiene Department of the Government of the Hong Kong
Special Administrative Region. Under no circumstances
should the research data contained herein be reproduced,
reviewed, or abstracted in part or in whole, or in
conjunction with other publications or research work
unless a written permission is obtained from the Department.
Acknowledgement is required if other parts of this
publication are used.
Correspondence:
Risk Assessment Section
Food and Environmental Hygiene Department
43/F, Queensway Government Offices,
66 Queensway, Hong Kong.
Email: enquiries@fehd.gov.hk
This study investigated the levels
of polycyclic aromatic hydrocarbons (PAHs) in different
barbecued meat and the effect of cooking methods on
PAH levels. PAHs refer to a large group of organic
chemicals that may be present in the environment as
pollutants, and they may be generated during the preparation
of barbecued meats. Some PAHs are considered as possibly
or probably carcinogenic to humans.
Two types of barbecued meats, namely
dried meat and ¡§Siu Mei¡¨ were studied. The types of
¡§Siu Mei¡¨ included in the study were BBQ pork, roasted
pork and roasted duck. A total of 60 barbecued meat
samples were collected from local food factories or
general restaurants, and control samples of boiled
pork and duck meat were also obtained. Laboratory
analysis for PAHs was conducted by the Food Research
Laboratory of the Food and Environmental Hygiene Department.
Results showed that grilling or roasting
would generate PAHs. Among the three methods of preparing
¡§Siu Mei¡¨, charcoal grilling gave rise to the highest
amount of PAHs when compared with gas grilling or
electric oven roasting. Grilling of meat at a lower
temperature or further away from the heat source would
result in lower levels of PAHs. PAHs were mainly found
in the outer part of barbecued meat. Dried meat prepared
by gas or electric grilling was found to contain similar
PAHs levels as formed in ¡§Siu Mei¡¨ prepared by charcoal
grilling.
Exposure to PAHs should be as low
as reasonably achievable. In preparing ¡§Siu Mei¡¨,
gas grilling or electric oven roasting is preferable
to charcoal grilling. When preparing barbecued meat,
measures should be taken to avoid meat from direct
contact with the flame and to avoid fat from dripping
onto the heat source. The meat could be grilled at
lower temperature and should not be overcooked. Members
of the public are advised not to overindulge in barbecued
meat particularly charcoal grilled ¡§Siu Mei¡¨ and the
¡§skin and fat¡¨ portion, to remove charred part of
the meat, and to have a balance diet with plenty of
fruits and vegetables.
OBJECTIVE
This study aims (i) to investigate
the levels of polycyclic aromatic hydrocarbons (PAHs)
in barbecued meat and (ii) to recommend appropriate
measures on the reduction of risks associated with
PAHs in barbecued meat.
BACKGROUND
Polycyclic Aromatic
Hydrocarbons
2. PAHs refer to a large group of
organic chemicals containing two or more fused aromatic
rings made up of carbon and hydrogen atoms. PAHs are
lipophilic and chemically stable.
3. Over 100 PAHs are present in the
environment as pollutants. PAHs are formed during
processing of coal, crude oil and natural gas, and
incomplete burning of coal, oil, gas, garbage, and
other organic substances. They are also present in
vehicle emissions and tobacco smoke. Some PAHs are
manufactured by industry and are used in the production
of PVC, plasticisers, pigments, dyes and pesticides.
They are ubiquitous in the environment, being present
in air, soil, water and food1.
Sources of Exposure
4. The main source of exposure to
PAHs for the adult is food, which contributed to more
than 90% of total exposure.1,2
However for smokers, significant contribution of PAHs
exposure may be attributed to cigarette smoking. The
additional intake of one of the PAHs, benzo[a]pyrene,
for a person smoking 20 cigarettes per day was estimated
to be 210 ng, which is in the same order of magnitude
of the mean intake from food (the mean benzo[a]pyrene
intake from food was about 110 ng per day).2,3
Other minor routes of exposure to PAHs are inhalation
of polluted ambient and indoor air, ingestion of house
dust, and dermal absorption from contaminated soil
and water.1
Occurrence in
diet
5. As PAHs are ubiquitous in the environment,
it is not surprising that they are present in almost
all food. For example, it has been reported that cereals
were found to contain PAHs at levels of 6 ¡V 14 mg/kg, fats and oils at 8 ¡V 11 mg/kg and seafood at 7 ¡V 8 mg /kg respectively.3,4
However, a high level of PAHs is not usually observed
in raw food.1
6. Food processing
or cooking steps such as roasting, grilling, barbecuing
and smoking generate PAHs and increase the level of
PAHs in the food being cooked.2
Charred food of almost any composition contains PAHs5
while only very low level of PAHs was detected when
food was cooked by some cooking steps such as steaming.
A study on the level of total PAHs formed in duck
meat showed that levels as high as 130 and 320 mg/kg were found when the duck meat was cooked by roasting
and charcoal grilling respectively, whereas only less
than 8.6 mg/kg was detected when cooked by steaming.6
7. In overseas studies, cereals were
found to be the main dietary source of PAHs, accounting
for some 27 to 35% of total dietary exposure, a result
probably due to the high amount of consumption.7
Although barbecued food only contributed a smaller
part of the PAHs intake, people with a diet rich in
roasted, barbecued or grilled, smoked food may have
significant intake of PAHs.2,
7
Formation during
processing or cooking
8. The exact mechanism of PAHs formation
in food processing or cooking is not precisely known.2
However, it is generally considered that incomplete
combustion is involved.2, 5,
8, 9 Regarding cooking
methods, a dry heat cooking method is often involved.
Pyrolysis of
fat and other organic matters on food
9. Formation of PAHs occurs through
pyrolysis of fat at temperatures of above 200oC2,
and is favoured at a temperature range of 500-900oC,
especially above 700oC.8
More PAHs is formed at higher cooking temperatures
10. Pyrolysis of other
organic matters such as proteins and carbohydrates
might be involved 10,
but the greatest concentrations of PAHs have been
shown to arise from fat pyrolysis.8
10. When food is in direct contact
with a flame, pyrolysis of fats in the meat generates
PAHs.5 Alternatively,
the melted fat from food dripping onto the heat source
generates PAHs and the PAHs will in turn be deposited
on the meat surface as the smoke rises. 2,
5, 9, 11,
12
Incomplete
combustion of fuel
11. Another possible mechanism for
the formation of PAHs is the incomplete combustion
of the fuel itself. Incomplete combustion of charcoal
generates PAHs 13, which
are brought onto the surface of the food and are adsorbed.12
Factors affecting
PAHs formation
12. A host of factors affecting PAHs
formation has been identified which include (i) the
distance of food from the heat source 5,
9, 10; (ii)
fat content of the food 1, 10;
(iii) duration of cooking1,
7, 9; (iv)
temperature used1; (v)
whether melted fat is allowed to drop onto the heat
source 7, 9;
and (vi) type of fuel used 7.
Toxicity
Toxicokinetics
and metabolism
13. PAHs are absorbed through the
gastrointestinal tract when ingested14.
After being absorbed, they are distributed throughout
the body, including almost all internal organs.1
14. The metabolism of PAHs is complex.
In short, PAH compounds undergo metabolic transformation,
forming either products that are excreted, or active
metabolites that can finally bind to DNA to form covalent
adducts. Given that DNA adduct formation is considered
as an initial event in chemical carcinogenesis, the
formation of active metabolites is considered to be
closely related to the carcinogenicity of PAHs.
Toxicity and
carcinogenicity
15. While the median lethal dose (LD50)
values of individual PAHs indicate that they have
moderate to low acute toxicity1,
carcinogenicity is the critical endpoint for health
risk evaluation of PAHs.15
16. Some PAHs have been shown to have
genotoxic effects both in vivo in rodents
and in vitro in mammalian (including human)
cell lines and prokaryotes.1
On the other hand, some PAHs do not appear to be genotoxic.
The genotoxicity of PAHs is summarised in Table
1.
17. The International Agency for Research
on Cancer (IARC) of the World Health Organization
has evaluated the carcinogenicity of some PAHs based
on evidence in human and experimental animals. The
IARC¡¦s classification of some PAHs are summarised
in Table 1. Most of the PAHs
evaluated are classified as Group 2B (possibly carcinogenic
to humans) or Group 3 (not classifiable as to its
carcinogenicity to humans). Three PAHs, namely, benzo[a]pyrene,
benz[a]anthracene and dibenz[a,h]anthracene, cause
greater health concerns since they are classified
as Group 2A (probably carcinogenic to humans). None
of the PAHs are classified as Group 1 (carcinogenic
to humans).
Table 1 : Genotoxicity and
Carcinogenicity of some PAHs
18. The carcinogenicity of the three
PAHs of more concern is summarised as follows. Benzo[a]pyrene,
when administered by the oral route, produced tumours
of the gastrointestinal tract (forestomach), liver,
lung and mammary glands of mice and rats.2,
16, 17 Dibenz[a,h]anthracene
and benz[a]anthracene produced tumours of the gastrointestinal
tract (forestomach), lungs and liver in mice.2,
17 Benz[a]anthracene also
induced papillomas of the forestomach in mice when
administered by gavage, and induced lung adenomas
and hepatomas in mice in another gavage study.
17
Level of safe
intake of PAHs
19. Since carcinogenicity is the critical
endpoint of toxicity of PAHs and that some PAHs are
genotoxic, it is not possible to define a level of
intake which is without possible risk.
20. Benzo[a]pyrene was the only PAH
compound that has been evaluated by the Joint FAO/WHO
Expert Committee on Food Additives (JECFA), but the
Committee was unable to establish a level of tolerable
intake for benzo[a]pyrene. The Committee however commented
that there was a large difference between estimated
human intakes of benzo[a]pyrene and the doses producing
tumours in animals. Thus any effects on human health
are likely to be small. Despite this, JECFA was of
the opinion that efforts should be made to minimise
human exposure to benzo[a]pyrene as far as practicable.16
21. JECFA and the Codex Committee
on Food Additives and Contaminants (CCFAC) have scheduled
to study food safety issues relating to PAHs in food
at their coming meetings to be held in 2005.
Barbecued Meat
22. ¡§Barbecued meat¡¨ is defined in
this study as meat cooked by a dry heat method. It
is a method of cooking without liquid. The heat is
transferred during the cooking process by convection
of dry air, radiation or conduction through a minimum
amount of hot fat. A golden brown, crispy crust with
a characteristic aroma is induced in the meat being
cooked. Examples of this kind of cooking method are
broiling, grilling, and roasting. Two types of barbecued
meat, namely dried meat and Cantonese-style barbecued
meat called ¡§Siu Mei¡¨, are discussed in greater details
below.
Dried meat
23. Dried meat (¦×°®) is a popular meat
snack commonly consumed in Asia. It is a thin slice
of grilled meat of varying sizes. Pork and beef are
the two commonest types of meat used for making dried
meat. Meat is placed on a metal rack and cooked above
or in between the heat source. The heat source could
be an electrical heating element or a naked flame.
Production flow of dried meat is illustrated in Annex
I.
Siu Mei
24. ¡§Siu Mei¡¨ (¿N¨ı) is a kind of Cantonese-style
meat dish. Marinated cuts of meat or whole animal
are cooked using a naked flame or other heat sources.
Being sold ready-to-eat, ¡§Siu Mei¡¨ is popular in Hong
Kong. It is consumed throughout the year and especially
popular during Chinese festivals and special occasions.
Examples of ¡§Siu Mei¡¨ are ¡§BBQ pork¡¨ (¤e¿N), ¡§roasted
pork¡¨ (¿N¦×) and ¡§roasted duck¡¨ (¿NÀn).
25. There is no standardised method
for the production of ¡§Siu Mei¡¨ and their processing
may vary among different manufacturers. The cooking
process of ¡§Siu Mei¡¨ usually takes place inside a
large oven or heating chamber of varying sizes. Different
cooking methods may be used to prepare ¡§Siu Mei¡¨,
such as grilling by charcoal or gas, and roasting
in an electric oven. Also, the position of heat source
relative to the food varies. Among the three types
of commonly consumed ¡§Siu Mei¡¨, roasted pork is grilled/roasted
normally with medium to high heat (over 330oC),
BBQ pork with medium heat (over 220oC)
whereas roasted duck is normally grilled/roasted with
low to medium heat (160 ¡V 200oC). The generic
flow charts illustrating the production of BBQ pork,
roasted pork and roasted duck are shown in Annexes
II, III and IV
respectively.
SCOPE OF STUDY
26. Given the public health significance
of PAHs, the Food and Environmental Hygiene Department
(FEHD) examined this issue by conducting a study to
determine the PAH levels in barbecued meat since (i)
barbecued meat is one of the most popular traditional
Chinese food in Hong Kong; (ii) they usually contain
high level of fats and their production involves processes
such as roasting and grilling which might introduce
PAHs to foods; and (iii) the level of PAHs in barbecued
meat can be reduced by appropriate measures.
27. This study covered dried meat
and ¡§Siu Mei¡¨. The effect of different cooking methods
on PAH levels in the barbecued meat was also studied.
PAH compounds analysed
28. Occurrence of a mixture of PAHs,
rather than any single compound of the group, is common.1
However, no specific list of PAHs to be analysed in
food is recommended by international bodies. In this
study, 15 PAHs, as listed in Table
1, including the three PAH compounds which were
classified as Group 2A by IARC, were analysed. Their
selection depends on their toxicity and availability
of testing of individual PAHs locally.
METHODS
Sampling plan
29. A survey was conducted in the
local market to obtain a list of premises that manufactured
barbecued meats including ¡§Siu Mei¡¨ and dried meat.
As a result, some 1000 premises manufacturing ¡§Siu
Mei¡¨ and 5 premises manufacturing dried meat were
identified in the local market. Of the premises that
manufactured ¡§Siu Mei¡¨, the majority (over 85%) used
gas grilling (town gas or liquid petroleum gas [LPG]),
about 10% used electric oven roasting, while less
than 2% of the premises used charcoal grilling including
wood grilling. Of the 5 premises that manufactured
dried meat, 2 of them used gas grilling and 3 used
electric grilling.
30. Dried meat and ¡§Siu Mei¡¨ prepared
by different cooking methods were sampled from the
premises in different parts of Hong Kong.
31. For the dried meat category, dried
beef (¤û¦×°®) and dried pork (½Ş¦×°®) were collected for
study. For the ¡§Siu Mei¡¨ category, BBQ pork (¤e¿N),
roasted pork (¿N¦×) and roasted duck (¿NÀn) were collected
for study. They represented three types of barbecued
meat, i.e., barbecued meat without skin (BBQ pork),
barbecued meat with thick crispy skin (roasted pork)
and barbecued meat with thin crispy skin (roasted
duck).
32. Based on the mechanisms for the
formation of PAHs, the cooking methods were categorised
into three groups, namely (i) charcoal grilling including
wood grilling, (ii) gas grilling including those using
LPG and town gas, and (iii) electric grilling (for
dried meat) / electric oven roasting (for ¡§Siu Mei¡¨).
33. Raw pork and raw duck meat samples
were also collected and boiled. They were then analysed
for PAHs and these served as the control and baseline
reference.
34. In order to study the distribution
of PAHs formed in the skin and lean meat, the roasted
duck samples were separated into two portions: (i)
skin and fat and (ii) lean meat, and they were analysed
separately.
Laboratory analysis
35. Laboratory analysis was performed
by the Food Research Laboratory of FEHD. All food
samples were homogenised and dried by lyophilisation.
A representative portion equivalent to about 5g sample
on wet basis was tested. This portion was saponified
and then extracted by cyclohexane and the extract
was cleaned up on solid phase extraction column, and
subsequently tested on the Gas Chromatograph - Mass
Spectrometer (GC/MS). C13-labelled PAH
was used as surrogate for the analysis. The limits
of detection (LOD) for the 15 PAHs ranged from 0.1
to 0.7 mg/kg respectively. The LOD are similar to those in overseas
studies with the similar analytical methods. Table
2 shows the list of PAHs analysed and their respective
limits of detection.
Table 2 : List of PAHs Analysed
and Limits of Detection
Data Analysis
36. For each sample tested, the levels
of the 15 PAHs analysed were summed to produce a ¡§total
PAHs¡¨ level while the levels of the three PAHs of
more concern were reported individually.
37. The levels of PAHs in roasted
duck were calculated from the sum of the proportional
concentrations in ¡§skin and fat¡¨ and ¡§lean meat¡¨ portions.
RESULTS
38. A total of 60 barbecued meat samples
were collected from food factories and general restaurants
manufacturing barbecued meat. The number of samples
taken in each food category was summarised in Table
3. In addition, nine samples each of raw duck
meat and raw pork were taken, blended into three composite
samples for each of duck meat and pork and were boiled
and they acted as controls.
Table 3: Number of Barbecued
Meat Samples Taken for PAHs Analysis
39. In all the control samples, levels
of benz[a]anthracene, benzo[a]pyrene and dibenz[a,h]anthracene
were all below detection limits while total PAHs levels
were low (Table 4).
40. Among all the barbecued meat samples,
55% of the test results were below LOD. PAH levels
varied widely among samples, including among samples
of the same food type prepared by the same cooking
method. The levels of PAHs among various food types
and cooking methods were given in
Table 5 and graphically presented in Annex
V.
Table 4 : Median Concentration
with Range for PAHs in Boiled Samples
Table 5 : Median Concentration
with Range for PAHs in Barbecued Meat Samples
41. The levels of total PAHs of barbecued
samples on the whole were significantly higher than
those of boiled samples (t-test, p<0.001).
Among the three PAHs of more concern, only benz[a]anthracene
and benzo[a]pyrene of barbecued samples were significantly
higher in levels than those of boiled samples (t-test,
p<0.001 for both cases). As for dibenz[a,h]anthracene,
no significant difference was found in levels between
barbecued and boiled samples as dibenz[a,h]anthracene
was not detected in most (94%) of the barbecued samples.
42. For all three types of ¡§Siu Mei¡¨
samples, samples that were prepared by charcoal grilling
were found to contain significantly higher levels
than those that were prepared by gas grilling or electric
oven roasting with respect to total PAHs (t-test,
p<0.001 for both cases), benz[a]anthracene
(t-test, p=0.001 for both cases) and benzo[a]pyrene
(t-test, p=0.002 for both cases). However,
no significant difference in PAH levels was detected
between those that were prepared by gas grilling and
electric oven roasting.
43. Among those ¡§Siu Mei¡¨ samples
that were prepared by charcoal grilling, roasted pork
(median concentration: 144.7 mg/kg) was found to contain the highest median concentration
of total PAHs, followed by BBQ pork (72.6 mg/kg) and roasted duck (48.6 mg/kg). However, analysis of variance did not show that
the differences were statistically significant. No
such pattern was observed for samples prepared by
gas grilling or electric oven roasting. No significant
difference in levels of benz[a]anthracene and benzo[a]pyrene
was found among different types of ¡§Siu Mei¡¨.
44. For roasted duck samples that
were prepared by charcoal grilling, significant higher
levels of total PAHs (median concentration: 105.6mg/kg) were detected in the ¡§skin and fat¡¨ portion than
those detected in the ¡§lean meat¡¨ portion (median
concentration: 2.1 mg/kg) (t-test, p=0.042). The same pattern was
observed in roasted duck samples that were prepared
by gas grilling (median total PAHs: 18.9 mg/kg for ¡§skin and fat¡¨ and 6.9 mg/kg for ¡§lean meat¡¨) or electric oven roasting (median
total PAHs: 8.7 mg/kg for ¡§skin and fat¡¨ and 7.0 mg/kg for ¡§lean meat¡¨)
but the differences were not statistically significant.
No significant difference in benz[a]anthracene and
benzo[a]pyrene levels was found.
45. For dried meat samples, no significant
difference in PAH levels was found between beef and
pork samples. As compared with samples that were prepared
by electric grilling, those prepared by gas grilling
were found to contain significantly higher levels
of total PAHs (t-test, p=0.027), benz[a]anthracene
(t-test, p<0.001) and benzo[a]pyrene (t-test,
p=0.001).
46. When comparing the levels of PAHs
in dried meat samples with those in BBQ pork samples
that were prepared by similar cooking methods, dried
meat samples were found to contain significantly higher
levels of the total PAHs (t-test, p<0.001),
benz[a]anthracene (t-test, p =0.006) and
benzo[a]pyrene (t-test, p=0.011).
DISCUSSIONS
Effect of cooking
methods
47. Results of the present study revealed
that grilling or roasting generated PAHs whereas charcoal
grilling gave rise to the highest amount of PAHs.
Although no significant difference was detected between
¡§Siu Mei¡¨ samples that were prepared by gas grilling
or electric oven grilling, significant higher level
was found in dried meats that were prepared by gas
grilling. The finding was consistent with those reported
elsewhere.2, 6,
16 On the other hand, PAH
levels in barbecued meat detected in our study were
in general lower than those reported in other studies
(see paragraph 6). This may be
due to a combination of factors, which may include
the design of heating chambers used in most of the
local ¡§Siu Mei¡¨ manufacturers that can avoid fat dripping
onto the heat source during grilling or roasting.
48. With reference to the results
from overseas studies, the levels of total PAHs in
our ¡§Siu Mei¡¨ samples that were prepared by gas grilling
or electric oven roasting were comparable with the
levels of total PAHs found in other foodstuffs such
as cereals, seafoods, oils and fats (ranged from 6
to 14 mg/kg).3, 4
Effect of cooking
temperatures
49. Our results showed that lower
levels of PAHs were detected in roasted duck when
compared with those in BBQ pork and roasted pork.
Roasted duck was in general cooked at a lower temperature
of below 200oC. The results were consistent
with the findings that lower PAHs were generated at
a lower temperature.10
Effect of distance
from the heat source
50. Our results showed that PAH levels
formed in dried meat were much higher than those in
BBQ pork that were prepared by the similar cooking
methods. This may be due to a larger surface area
per unit weight for dried meat and that the meat was
cooked at a closer distance to the heat source in
grilling dried meat than in preparing BBQ pork.
Distribution of
PAHs
51. Our results showed that in roasted
duck, the PAHs were concentrated on the ¡§skin and
fat¡¨ portion (i.e., the outer layer) of the roasted
duck. The results were consistent with the postulation
that PAHs were produced mainly on the outer surface
of barbecued food1 where
the food was closer to the heat source and was subject
to higher temperature. Also, PAHs generated by incomplete
combustion of the fuel were also absorbed by the outer
surface of the meat.
Effect of fat content
52. Although it has been mentioned
in literature that the formation of PAHs is related
to the fat content of the meat7,
the associations between fat contents in the final
products and PAH levels were inconsistent among different
types of barbecued meat in our study.
Limitations
53. This study examined the effect
of different cooking methods on the generation of
PAHs. It did not, however, take account of the exact
processing of the barbecued meat. For example, the
position of the food relative to the heat source may
be different in different cooking methods or different
manufacturers. Moreover, as there is no standardised
method for the production of barbecued meat, the actual
practices may vary even with the same cooking method,
and this may affect the formation of PAHs. Also, the
heating power, especially in charcoal and gas grilling,
may vary between batches. Therefore, it was not surprising
why the PAH levels in barbecued meat varied even with
the same cooking methods.
Other issues
54. There is a trend that the barbecued
meat industry is switching from using charcoal to
using electric and gas grilling. The change is partly
due to the fact that new buildings usually do not
cater for the ventilation structure which is needed
for charcoal burning.
CONCLUSION AND RECOMMENDATIONS
55. Among the three types of cooking
methods, charcoal grilling gave rise to the highest
PAHs levels in ¡§Siu Mei¡¨ as compared with gas grilling
or electric oven roasting. Grilling of meat at a lower
temperature or further away from the heat source would
result in lower levels of PAHs. PAHs were found mainly
in the outer part of barbecued meat.
56. Dried meat prepared by gas or
electric grilling was found to contain levels of PAHs
similar to those in ¡§Siu Mei¡¨ prepared by charcoal
grilling.
57. As exposures to PAHs should be
as low as reasonably achievable, appropriate measures
should be taken to lower their exposures. The following
advices are given to the trade and consumers on the
reduction of risks associated with PAHs in barbecued
meat.
Advice to trade
(a) For making ¡§Siu Mei¡¨, gas grilling
or electric oven roasting is preferred to charcoal
grilling. For making dried meat, electric grilling
is preferred to gas grilling.
(b) Heating chamber should be properly
designed to avoid fat dripping onto the heat source.
(c) When barbecuing meat:
i. Direct contact of meat with
flame should be avoided. This could be achieved
by placing the meat further from the heat source.
ii. Fat dripping onto the heat
source should be avoided. This could be achieved
by trimming the visible fat from meat before barbecuing.
iii. Meat could be cooked at
lower temperature and avoid overcooking. However,
the meat should be cooked thoroughly to destroy
foodborne pathogens.
iv. Prior to grilling or roasting,
the meat could be cooked partially by a method
which employs a lower cooking temperature such
as boiling.
Advice to consumers
(a) Do not overindulge in barbecued
meat, particularly charcoal grilled ¡§Siu Mei¡¨ and
the ¡§skin and fat¡¨ portion.
(b) Remove the charred parts of
food.
(c) Have a balanced diet and eat
more fruits and vegetables.
(d) When going for barbecuing,
members of the public are advised to
i. trim visible fat from meat
before barbecuing;
ii. partially cook the meat,
e.g. by boiling, before barbecuing;
iii. avoid dripping fat onto
the charcoal when barbecuing meat by putting the
charcoal on sides of the stove and grilling food
in the centre;
iv. consider to grill meat in
foil packets to avoid contamination from smoke
and flame; and
v. place the meat further from
the heat source when barbecuing meat and avoid
overcooking of meat. However, the meat should
be cooked thoroughly to destroy foodborne pathogens.
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Last
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