Food Alert - A kind of prepackaged flour with possible Escherichia coli contamination 食物警報 - 一款可能受大腸桿菌污染的預先包裝麵粉

Dear Sir/Madam,

We have issued a food alert regarding "A kind of prepackaged flour with possible Escherichia coli contamination".

Please check the following link for further details.
http://www.cfs.gov.hk/cgi-bin/cfsnew/fa/foodalert_e.pl?record=180

For further enquiries, you may contact us at <rc@fehd.gov.hk>.
Should you wish to cancel your registration with E-news, please notify us either by email (same address as above) or by fax (no. 2893 3547).

Centre for Food Safety

***********************************************************

各位先生/女士：

我們剛發出關於"一款可能受大腸桿菌污染的預先包裝麵粉"的食物警報。

詳情請參閱以下連結:
http://www.cfs.gov.hk/cgi-bin/cfsnew/fa/foodalert_c.pl?record=180

如有任何查詢，請與我們聯絡(電郵地址：rc@fehd.gov.hk)。
如想取消[食物安全電子信息]的用戶登記，請透過上述電郵地址或傳真號碼 2893 3547 通知我們。

食物安全中心


 

Food Alert - A batch of milk imported without import permission 食物警報 - 一批未經批准進口的牛奶

Dear Sir/Madam,

We have issued a food alert regarding "A batch of milk imported without import permission".

Please check the following link for further details.
http://www.cfs.gov.hk/cgi-bin/cfsnew/fa/foodalert_e.pl?record=179

For further enquiries, you may contact us at <rc@fehd.gov.hk>.
Should you wish to cancel your registration with E-news, please notify us either by email (same address as above) or by fax (no. 2893 3547).

Centre for Food Safety

***********************************************************

各位先生/女士：

我們剛發出關於"一批未經批准進口的牛奶"的食物警報。

詳情請參閱以下連結:
http://www.cfs.gov.hk/cgi-bin/cfsnew/fa/foodalert_c.pl?record=179

如有任何查詢，請與我們聯絡(電郵地址：rc@fehd.gov.hk)。
如想取消[食物安全電子信息]的用戶登記，請透過上述電郵地址或傳真號碼 2893 3547 通知我們。

食物安全中心


 

Food Alert - Excessive metallic contaminant found in dried lily bulb sample 食物警報 - 預先包裝乾百合樣本金屬雜質含量超出法例標準

Dear Sir/Madam,

We have issued a food alert regarding "Excessive metallic contaminant found in dried lily bulb sample".

Please check the following link for further details.
http://www.cfs.gov.hk/cgi-bin/cfsnew/fa/foodalert_e.pl?record=178

For further enquiries, you may contact us at <rc@fehd.gov.hk>.
Should you wish to cancel your registration with E-news, please notify us either by email (same address as above) or by fax (no. 2893 3547).

Centre for Food Safety

***********************************************************

各位先生/女士：

我們剛發出關於"預先包裝乾百合樣本金屬雜質含量超出法例標準"的食物警報。

詳情請參閱以下連結:
http://www.cfs.gov.hk/cgi-bin/cfsnew/fa/foodalert_c.pl?record=178

如有任何查詢，請與我們聯絡(電郵地址：rc@fehd.gov.hk)。
如想取消[食物安全電子信息]的用戶登記，請透過上述電郵地址或傳真號碼 2893 3547 通知我們。

食物安全中心


 

E-news 18.05.2017

致食物安全電子資訊訂閱者:
Dear E-news recipients,

以下資訊已上載到食物安全中心(中心)網站:
News on the Centre for Food Safety (CFS) online:

低鹽低糖正面標籤設計比賽、低鹽低糖我識揀標語創作暨海報設計比賽
Low-Salt and Low-Sugar Front-of-pack Label Design Competition, Smart Choices for Low-Salt and Low-Sugar Slogan Writing cum Poster Design Competition

政府聯同降低食物中鹽和糖委員會現正舉辦「低鹽低糖正面標籤設計比賽」(「標籤設計比賽」)和「低鹽低糖我識揀標語創作曁海報設計比賽」(「標語創作曁海報設計比賽」)，藉此鼓勵市民培養少鹽少糖的健康飲食習慣。「標籤設計比賽」歡迎公眾人士參加；「標語創作曁海報設計比賽」歡迎中小學生參加。
The Government and the Committee on Reduction of Salt and Sugar in Food are jointly organising the Low-Salt and Low-Sugar Front-of-pack Label Design Competition and the Smart Choices for Low-Salt and Low-Sugar Slogan Writing cum Poster Design Competition, with a view to encouraging the public to adopt a healthy dietary habit with low intake of salt and sugar. Members of the public are welcome to join the Label Design Competition. Primary and secondary school students are welcome to join the Slogan Writing cum Poster Design Competition.

詳情請參閱以下網頁：
Please click on this webpage for details:

中文:
http://www.cfs.gov.hk/tc_chi/whatsnew/whatsnew_act/Websites_for_Label_Poster_Design_Competition.html
English:
http://www.cfs.gov.hk/english/whatsnew/whatsnew_act/Websites_for_Label_Poster_Design_Competition.html

 

2017年3月份食物安全報告
Food Safety Report for March 2017

中心會每月公布「食物安全報告」，分享食物監察結果，令市民可適時地獲得最新的食物安全資訊。
As a way to deliver the latest food safety information timely to the public, the CFS announces the "Food Safety Report" every month, sharing the food surveillance results.

有關之新聞公報可瀏覽以下網頁:
Please click on this webpage for the related press release:

中文 :
http://www.cfs.gov.hk/tc_chi/press/20170428_0838.html
English:
http://www.cfs.gov.hk/english/press/20170428_0838.html

 

食安中心公布粽子時令食品調查 (第一期) 結果
CFS announces results of seasonal food surveillance on rice dumplings (first phase)

中心最近完成一項有關粽子的時令食品調查（第一期)。在四十多個粽子樣本中，除較早前公布的一個散裝鹼水粽樣本被檢出含不准在食物中使用的防腐劑硼酸外，其餘樣本全部通過檢測。
The CFS announced the results of a recently completed seasonal food surveillance project on rice dumplings (first phase). Except for a loose-packed "gan shui" rice dumpling sample found to contain boric acid, a preservative not permitted in food, which was announced earlier, the test results of some 40 samples collected were satisfactory.

有關之新聞公報可瀏覽以下網頁:
Please click on this webpage for the related press release:

中文:
http://www.cfs.gov.hk/tc_chi/press/20170428_0839.html
English:
http://www.cfs.gov.hk/english/press/20170428_0839.html

食物安全中心
Centre for Food Safety

 

Food Alert - Undeclared allergen (milk) found in prepackaged coconut milk powder 食物警報 - 預先包裝椰漿粉含未有標示致敏物（奶類）

Dear Sir/Madam,

We have issued a food alert regarding "Undeclared allergen (milk) found in prepackaged coconut milk powder".

Please check the following link for further details.
http://www.cfs.gov.hk/cgi-bin/cfsnew/fa/foodalert_e.pl?record=177

For further enquiries, you may contact us at <rc@fehd.gov.hk>.
Should you wish to cancel your registration with E-news, please notify us either by email (same address as above) or by fax (no. 2893 3547).

Centre for Food Safety

***********************************************************

各位先生/女士：

我們剛發出關於"預先包裝椰漿粉含未有標示致敏物（奶類）"的食物警報。

詳情請參閱以下連結:
http://www.cfs.gov.hk/cgi-bin/cfsnew/fa/foodalert_c.pl?record=177

如有任何查詢，請與我們聯絡(電郵地址：rc@fehd.gov.hk)。
如想取消[食物安全電子信息]的用戶登記，請透過上述電郵地址或傳真號碼 2893 3547 通知我們。

食物安全中心


 

E-news on 04.05.2017

致食物安全電子資訊訂閱者:
Dear E-news recipients,

以下資訊已上載到食物安全中心(中心)網站:
News on the Centre for Food Safety (CFS) online:

食物安全焦點(2017年4月第129期)
Food Safety Focus (129th Issue, April 2017)

今期熱門焦點包括:
The topics of the current issue are:

· 二零一六年有關食肆及食物業的食源性疾病個案回顧
· Review of Foodborne Disease Outbreaks Related to Food Premises and Food Business in 2016
· 在肉類中使用食物添加劑
· The Use of Food Additives in Meats
· 巴西肉類事件
· Brazilian Meat Incident

歡迎到以下網頁閱覽上述月刊:
You are most welcome to browse through the publication at:

中文:
http://www.cfs.gov.hk/tc_chi/multimedia/multimedia_pub/multimedia_pub_fsf.html
English:
http://www.cfs.gov.hk/english/multimedia/multimedia_pub/multimedia_pub_fsf.html

已獲小量豁免產品名單
List of Small Volume Exemption Products

根據小量豁免制度，在香港每年銷售量不超過30,000件的相同版本預先包裝食物，可獲授予營養標籤豁免。有關豁免產品名單已上載中心網頁。
Under the Small Volume Exemption (SVE) Scheme, prepackaged foods of the same version with annual sales volume in Hong Kong not exceeding 30,000 units may be granted with exemption from providing nutrition labelling. List of SVE products has been uploaded onto the CFS website.

詳情請參閱以下網頁:
Please click on this webpage for details:

中文:
http://www.cfs.gov.hk/tc_chi/programme/programme_nifl/files/SVE_exempted_product_c.pdf
English:
http://www.cfs.gov.hk/english/programme/programme_nifl/files/SVE_exempted_product_e.pdf

食物安全巡迴展覽
Roving Exhibition on Food Safety

5月的巡迴展覽內容包括營養標籤、預防食物交叉污染、雪卡毒素、食物安全條例、控制食物温度、基因改造食物、食物安全5要點、反式脂肪、避免食用河豚及食物含丙烯酰胺。展覽將設於石塘咀街市、渣華道街市、香車街街市、花園街街市及官涌街市。
The coming exhibitions will be held in May at Shek Tong Tsui Market, Java Road Market, Heung Che Street Market, Fa Yuen Street Market and Kwun Chung Market.  Panels cover topics on Nutrition Labelling, Prevention of Cross-contamination, Ciguatoxins, Food Safety Ordinance, Control of Food Temperature, Genetically Modified Food, 5 Keys to Food Safety, Trans Fats, Avoid Consuming Puffer Fish and Acrylamide.

請點擊查看具體時間:
Please click to see the schedule:

中文:
http://www.cfs.gov.hk/tc_chi/whatsnew/whatsnew_act/whatsnew_act_Roving_Exhibition_2017.html

English:
http://www.cfs.gov.hk/english/whatsnew/whatsnew_act/whatsnew_act_Roving_Exhibition_2017.html

食物安全中心
Centre for Food Safety

 

Question from a student 20170503e

Q:

Sorry for bothering. May I know what is the minimum pH limit of

i) E.coli

ii) Salmonella?

Is adjusting pH to 4.2 effective in controlling their growth respectively?

Since there are many different data that confuse me.

A:
pH 4.2 should be effective in controlling the growth of most E. coli and Salmonella strains. However, some E. coli serotypes, such as O157:H7, can survive at pH 4.2. You have to note that minimum, optimum, and maximum of whatever microorganisms are affected by many factors, including their own biology, other environmental factors, and growth stages, there is no absolute limit. They are at best approximations. That is a reality. We can only note the limits as general features not absolutely applicable to all strains of a species.  

Question from a student 20170503d

Q:

I have some questions concerning 2014-2015 Past Paper B2.

I think the implicated microorganism should be Staphylococcus aureus but the incubation period of 11-40 hours is not so consistent with that of the Staphylococcus aureus. Does it mean that as long as the calculated incubation period is longer than the incubation period of the microbe itself, it can be considered as consistent?

And the difference in attack rate of roast turkey is also quite high and there are also Clostridium perfringens detected in the roast turkey. The incubation period also matches. Can we also deduce it is the agent that cause the outbreak?

One more question is that if the microbes mentioned in the questions do not fit in the analysis, we can suggest some possible microbes by ourselves?

And may I also ask if Listeria monocytogens can grow at 40C? If yes, that means heat treatment at 40C is not effective in suppressing its growth?

A: 

The incubation period is a little too long. You have to discuss this point when you answer the question. But the pizza has the highest attack rate difference, which is an important factor for the implicated food. The roast turkey can also be a suspected food but it is less likely than the pizza. 

If the microbes resulted from the investigation do not fit totally with the deduction, you can of course suggest other possibilities.

Listeria can grow at 40C, so 40C is not effective in suppressing its growth

Question from a student 20170503c

Q:

From the outbreak investigation questions in the past papers, part (a) asks about the suspected food and part (b) asks about the implicated food.

I would like to ask:

     1) for answering the suspected food, do we ONLY use the attack rate difference to deduce the answer?

     2) is it necessary that the suspected food MUST BE THE SAME as the implicated food?

For 2012-2013 Q8, are these answers correct?

       (a) Pizza is the suspected food as it has the highest attack rate difference among the others. One point needs to be aware that there is no bacteria found in pizza.

       (b) B. cereus is the implicated microorganism as it is consistent to the shortest incubation period (5 hours) while C. perfringens is not. Therefore, the implicated food is bread

A: 

I do not have the 2012-13 question at hand, so I just answer according to my memory of the questions.

1. You can use whatever evidence you think appropriate to deduce the suspected food. The attack rate difference is an important factor in the deduction or elimination. Especially when the difference is very small or negative.
2. Suspected food and implicated food can be different. 

a. No bacteria does not mean the food is clean. There can be toxins.

b. The bread, if having a very small attack rate difference, or negative attack rate difference, would probably not the implicated food. It is possible that the pizza had Staphylococcus aureus grown on and toxin produced. 

Question from a student 20170503b

Q:
I found that the incubation periods (IP) of some of the bacteria are inconsistent in concept maps and the food microbiology notes. For instance, the IP of Clostridium botulinum is 8hours to 8 days as written on the concept map and said during class but that in the note of p.A-1 is 1.5-3days. For Staphylococcus aureus, the IP written on concept map is 2-6hrs and that on p.A-1 of the note is 1-6hrs. For Campylobacter jejuni, the IP is 2-9days on ppt notes but that on p.A-2 of note is 2-7 days. Should I refer the incubation period of bacteria and virus on the notes or on the concept maps? Thanks for your kind attention!

A:
As I have mentioned many times in my lectures that the incubation period for each pathogen is only an approximation. You will find that the incubation periods from different sources are not exactly the same, even from my concept map and notes. Due to two reasons, at least,

1. Many environmental factors would affect the incubation period.
2. Each species may have many strains and incubation periods for them may be different.

So use the approximate incubation period from either notes or concept maps would be acceptable.

Question from a student 20170503a

Q:
Hello Mr Kwan, i would like to ask if we could bring self-prepared notes to the exam?
Thank you so much!

A: Yes, of course

Question from a student 20170503a

Q and A

• 2014-2015 B2. If I know that the suspected food is pizza from (a), do I also need to calculate the incubation period assuming dinner is the problem? 

Yes, you should check every piece of information to ensure your conclusion is close to the truth.

• I dont understand what you mean by elimination. Do I need to refer to every other food served at the picnic and its attack rate? (eg. Although Salmonella entericaserotype Typhimurium is found in both the sushi and faeces of patients, it seems that sushi is not likely to be the food of problem as it has the lowest positive difference between the attack rate of those who ate and those who didn’t. ) 

Yes, eliminate other possibilities with information at hand. For example, S Typhimurium in this case would probably not the agent because of the attack rate and incubation time are not consistent with it being the agent. You have to do this because disease may not be caused by a single pathogen but may be caused by more than one. You also need to explain any inconsistence observed.

• 2013-2014 QB1 (b) x : Occurred frequently in child-care centers : Human rotavirus. Is this correct? 

No, should be Norovirus

• 2014-2015 QB1 (b)viii : Occurrence and growth in fresh cream even stored in refrigerator: Listeria monocytogenes

Yes, it can grow at refrigeration temperature and may exist in fresh cream

• 2014-2015 QB1 (b) Occurred frequently in child-care centers and caused vomiting: Is it nora virus or human rotavirus? 

Norovirus is the better choice.

Question from a student 20170502a2

Q & A:

Thank you Professor Kwan. I am sorry that I would like to ask 2 more questions. 

1) Can Salmonella and E. coli tolerate high salt content? And in specific, can E. coli survive/grow in food with salt content 7%?

E. coli cannot grow at 7% salt, but it may survive.

2) Clostridium botulinum cannot grow in food with oxygen 5% since it is an obligate anaerobe?

It cannot grow with 5% oxygen.

Question from a student 20170502a1

Q: 

I would like to ask how to determine 'growth' and 'survival' of microorganisms from some given data. 

For 'growth', if the parameters are out of the minimum or maximum limit of microorganisms, it means that they cannot grow?

A: They cannot grow

Q:

For 'survival', I remembered that you have mentioned microorganisms can actually survive at low temperature and low water activity, even if the conditions are out of their limit. How about pH? Will they just die if the pH is below minimal limit/above maximum limit? And for temperature that is higher than the maximal temperature for growth, does it mean that the microorganisms will die?

A: 

pH below minimum or above maximum: Die.

temperature higher than maximum: Die.

But of course, the length of time for the microorganisms expose to these parameters needs to be taken into consideration. If brief exposure, there is D value or similar factors affecting the survival.

Question from a student 20170502d

Question about  pastpaper 2013-2014

I would like to know  how to calculate new D value like question in B5 (d).
And do you mind checking if the following ans in B5 is correct?
a. no. of D's 
Spoilage bacteria = 100D
Bacterial spores = 10D
Fungal spores = 50D
b.

Spoilage bacteria = 10^-95

Bacterial spores = 10^ -6

Fungal spore = 10^-49

c. the standard canning process for  Spoilage bacteria and  Fungal spore are sufficient, but not for bacterial spores

A: You are correct, but you should show your calculation too, also need to explain.

Please see https://fnsc3180hsk.blogspot.hk/2017/05/question-from-student-201617-20170501a.html?showComment=1493708599366#c8295958764595042514

Question from a student 20170502c

Q:
     I have a question popped up in my mind when I looked at the notes of fermentation.  "Lactic acid production can lower the pH to make the fermented food resistant to spoilage." If this is true, then why do fermented foods like cheese, yoghurt still subject to spoilage? Thank you for your attention.

A: 
1." Resistant to spoilage" does not mean never spoiled, only less likely to be spoiled, not high risk for spoilage.
2. In fact, cheese and yogurt do not spoil easily.

Question from a student 20170502b

Q&A:    

 I would like to ask that whether notes content in pages below will be covered in final examination? Coz I am not sure about these contents are related to lectures topics or not. Thanks.

1. Soybean paste 

NO

2. Clostridium difficile 

NO

3. Notes P.34-40 Protozoa and parasitic worms

NO

4. Notes P.41-45 fungal toxins in foods 

NO

5. Notes P.101-106 controversial preservation: nitrite,nitrate,antibiotics and food irradiation 

NO

6. Notes P.107-111 legal considerations and food safety programs

Yes, we have discussed HACCP. HACCP is included.

Question from a student 20170502a

Q&A:
 I would like to ask for the answer of B2 and B3a in 14-15 pastpaper. For B2, is the most suspected food Roast Turkey?

No. According to differences in attack rates and incubation period, and other evidences, it is probably Pizza and Staphylococcus aureus.


 For B3a, drying means heat drying that lowers the aw? For the comparison made, that means in this case, we have to point out lowering pH is more effective in preserving food? 

Yes, lowers Aw and water content.

No, lowering pH is not more effective in preserving food.



Lastly, can I answer all the questions in exam? Thanks a lot!

Yes, but if you answer all the questions, I will only count the number of questions required which have higher marks.

Some more Q&A from another email:


Also, as I see from the approach of doing 14-15 B4(e), the last question about justifying the answer and explain, that means we have to first find out the D value at 120°C, then calculate the treatment time required for both bacteria in regular blot ( spoilage bacteria: 10D x 0.0079= 0.079min, spores: 9D x 0.25= 2.25min), both bacteria in contaminated blot (spoilage: 0.1027min, spores: 3mins), then we use 3 mins at 120 degree celsius as the new time, then we follow part a to c to calculate the corr. D values, cell densities for both bacteria, then we come with conclusion to see if new method is ok. Am I correct?

You have to carry out all the calculations and answer both (i) and (ii). Your calculation to reach the two treatment times already shows whether the times you concluded to use are long enough to achieve the goals. "Justify" means you have to indicate why the times you use are good ones, "explain" means you need to give some details on your calculation and justification.

Review session 1, 2016-17. Reviewed questions Corrections

^

|

This was a mistake: The question asked about the standard process, so should use D values of the target organisms and time used in the standard process to calculate. 

Question from a student 201617, 20170501a

Q:

Dear Professor Kwan,

I have some problems regarding the past papers. Thank you for your attention.

‘What are the number of D’s targeted in the standard canning process for each of these microorganisms?’ has been asked in 2013-2014 and 2014-2015 past papers. However, as I check the answers from the blog, I find that 2 different approaches are used to answer the same type of question.

1) 2013-2014: Use ‘time in standard canning process/D value for each microorganisms’ for calculation

2) 2014-2015: Use data of ‘approximate densities of microbial flora in the ham before canning’ and ‘acceptable cell density in canned ham’ for calculation

Which one should we use in the examination? The question is asking about the ‘real target of the canning process that can be achieved’ (1) or the ‘ideal target of the canning process’ (2)?

Can you please also help me check the answer of the question below? Thank you very much.

2013-2014 B5 (d) Cell densities of the microorganisms of the regular lot of ham after canning with the new process

	New D value at 120C	No. of D	Cell densities
Spoilage bacteria	0.0025	3min./0.0025=1200	100*10^(-1200) =10^(-1198)/ml
Bacterial spores	0.25	3min./0.25=12	10*10^(-12) =10^(-11)/ml
Fungal spores	0.05	3min./0.05=60	1*10^(-60) =10^(-60)/ml

Since 10^(-11)/ml < 10^(-8)/ml (acceptable cell density in canned ham), the new process can replace the standard canning process.

A: 

‘What are the number of D’s targeted in the standard canning process for each of these microorganisms?’ has been asked in 2013-2014 and 2014-2015 past papers. However, as I check the answers from the blog, I find that 2 different approaches are used to answer the same type of question.

1) 2013-2014: Use ‘time in standard canning process/D value for each microorganisms’ for calculation

2) 2014-2015: Use data of ‘approximate densities of microbial flora in the ham before canning’ and ‘acceptable cell density in canned ham’ for calculation

The calculation should use 1). 2) was a mistake I made during discussion in review session or email responses this year.  

Which one should we use in the examination? The question is asking about the ‘real target of the canning process that can be achieved’ (1) or the ‘ideal target of the canning process’ (2)?

Should be (1) the ‘real target of the canning process’ (1)

In fact, don't mind whether it is "real or ideal target", as long as the question asked about the standard process, use the standard process to calculate the D value numbers.

Can you please also help me check the answer of the question below? Thank you very much.

2013-2014 B5 (d) Cell densities of the microorganisms of the regular lot of ham after canning with the new process

	New D value at 120C	No. of D	Cell densities
Spoilage bacteria	0.0025	3min./0.0025=1200	100*10^(-1200) =10^(-1198)/ml
Bacterial spores	0.25	3min./0.25=12	10*10^(-12) =10^(-11)/ml
Fungal spores	0.05	3min./0.05=60	1*10^(-60) =10^(-60)/ml

Since 10^(-11)/ml < 10^(-8)/ml (acceptable cell density in canned ham), the new process can replace the standard canning process.

Correct

thank you for pointing out the inconsistency that was a mistake in the review session this year.