4th Issue 2008

Feature Articles

(I) Learn the 5 Keys to Food Safety to minimise hazards and risks

Proper food handling can effectively prevent foodborne diseases. Based on the recommendations of the World Health Organization, the Centre for Food Safety has formulated the "5 Keys to Food Safety" to promote the proper handling of food to the public.

Learn the 5 Keys to Food Safety to minimise hazards and risks

What are the 5 keys to Food Safety?

    II. Enjoying "Poon Choi" in Winter

    Winter is the perfect time for enjoying "poon choi". As "poon choi" comprises a great variety of food ingredients and the preparation involves a number of processing steps and takes a relatively longer time, cross contamination is more likely to occur. Therefore, food handlers should pay attention to various risks when preparing "poon choi" so as to ensure food safety and avoid causing food poisoning incidents.

    Plan the Preparation of "Poon Choi" Well :

    1. Estimate the required manpower, ingredients, space and cooking utensils as early as possible, pay special attention to the need for sufficient stoves, refrigerating equipments and hot holding equipments;
    2. Do not take orders that you cannot meet;
    3. Time the preparation of all foods as precisely as possible so that each food is cooked at the right time. Avoid cooking perishable food too early.

    Purchasing of Ingredients and Receiving:

    1. Purchase quality food ingredients from reputable suppliers;
    2. When receiving food ingredients, check the quality, e.g. whether the packaging is intact and whether the storage temperature is appropriate, etc.

    Storage Facilities and Temperature Control

    1. Adopt "first-in-first-out" principle for food storage;
    2. Reserve sufficient space in the refrigerator for storing food ingredients. The temperature of the fridge and freezer should be kept at or below 4 C and -18 C separately;
    3. When raw and cooked foods are stored in the same refrigerator, cooked food should be kept above raw food to prevent cross contamination;
    4. Cooked food should be kept above 60 C and should be covered properly to prevent cross contamination.

    Food Preparation

    1. All food contact surfaces such as dining utensils, cutting boards and cooking utensils should be cleansed and sanitised thoroughly before preparing "poon choi";
    2. Thaw frozen food in the fridge or under running water;
    3. Cook all food thoroughly and store them separately to avoid cross contamination.

    Personal Hygiene

    1. Maintain good personal hygiene. Food handlers with symptoms of infectious diseases like gastroenteritis and flu should stop handling food;
    2. Wash hands thoroughly with warm water and liquid soap before handling food, after going to the toilet or touching dirty things (such as disposing of refuse).


    1. Deliver the "poon choi" to its destination as soon as possible and avoid keeping it at room temperature for a prolonged period of time;
    2. Keep the "poon choi" in a clean and covered insulated container;
    3. Keep the delivery vehicle clean.

    Reminding Customers How to Handle "Poon Choi"

    1. Remind customers to consume the "poon choi" as soon as possible;
    2. Remind the customers to store the "poon choi" in a refrigerator within two hours and reheat it thoroughly before consumption if it is not consumed immediately;
    3. Tell the customers how the "poon choi" should be reheated and whether the original container can be used for reheating.

    Reminding Customers How to Handle

    III. Observe good hygiene practices when enjoying hotpot

    Observe good hygiene practices when enjoying hotpot

    As the weather is getting cold, many people in Hong Kong love to gather around the table to enjoy hotpot. With various ingredients, including meat, vegetables and seafood such as shellfish and raw oysters, hotpots are served with different "soup bases" and condiments. Food in hotpot is indeed savoury. There are, however, potential risks in enjoying hotpot. If the food is not handled properly or not thoroughly cooked, it may contain pathogens such as Escherichia coli, Vibrio cholera, Vibrio parahaemolyticus, Norovirus, Hepatitis A virus and parasite larvae, which may cause food poisoning or other intestinal infection.

    To ensure food safety and maintain good business reputation, the restaurant management must strictly follow the "Five Keys to Food Safety" when serving hotpot to customers to minimise their risk of getting sick.

    1. Purchase fresh ingredients
      • Buy ingredients from reputable licensed suppliers.
      • Upon receipt of the food ingredients, check whether the food is fresh, packaging is intact and read the food labels on the packages, to avoid buying contaminated or expired food items.
      • Keep the invoices for 60 days so that problematic food can be traced.
    2. Store food in suitable environment and at appropriate temperature
      • Fresh hotpot ingredients should be put in a clean container with cover and stored in a refrigerator at or below 4 o C until they are to be served.
      • Never thaw food at room temperature to prevent bacterial growth. Frozen food should be thawed in fridges or microwave ovens.
      • Do not display too many food items, and the food displayed should not be kept at room temperature for more than 2 hours. The area for display of food should always be kept clean.

    3. Keep food, utensils and hands clean
      • Wash food ingredients thoroughly. Vegetables should be washed and then soaked in clean water for about an hour before serving.
      • Handle shellfish with care. Scrub and wash the shells and keep them in clean water for at least half a day to allow self-purification, and remove their internal organs.
      • Food handlers must observe good personal hygiene. They must wash their hands thoroughly with liquid soap and warm water before and after handling food, and after going to the toilet.
      • Bowls and dishes that have been used for holding raw food must be thoroughly
      • cleaned and sanitized before reuse.

    4. Handle raw food and cooked food separately
      • Provide customers with two separate sets of chopsticks and utensils for handling raw food and cooked food separately to avoid cross contamination.
      • Raw food and cooked food should be kept separately to reduce the risk of cross contamination.

    5. Cook food thoroughly
      • Fish and meat should be cut into thin slices. Meatballs should be cut open in the centre to speed up heating.
      • Advise customers verbally or by notices to remind them to cook food thoroughly before consumption.

    IV. Apply Desiccant Safely

    To preserve quality, control humidity, minimise mould growth and extend shelf-life, desiccants are added to the packaging of many pre-packaged food in the market, such as ready-to-eat seaweeds, biscuits or pastries. Two most commonly used desiccants are silica gel and calcium oxide.

    Silica gel / silica dioxide is a natural mineral which changes to molecular or bead form after purification and processing. It is chemically and biologically inert. Therefore, no harmful health effects will be caused even if they are accidentally ingested in small amount.

    Calcium oxide, also called quicklime, is a white powder which can control humidity effectively by keeping the relative humidity below 10%. It is widely used for packaging dehydrated foods or foods that need to be stored in environment with low humidity (e.g. biscuits or pastry food). In contact with moisture, calcium oxide becomes caustic and may cause burning sensation, stomach cramps and diarrhoea if swallowed accidentally.

    Other desiccants include activated carbon, clay and calcium chloride, etc. They are less commonly used due to higher cost.

    There are occasional incidents of accidental consumption of desiccants. To prevent accidental consumption by consumers and to avoid the hazard caused by food mixing with desiccants, food manufacturers are advised to follow the recommendations below:

    1. Use food-grade desiccants.
    2. The desiccant used should be properly sealed, e.g. sealed in small sachets. Upon exposure to the air, desiccant may become liquefied, resulting in leakage.
    3. The sealed sachet containing the desiccant should be made of food grade material and use non-toxic ink for printing.
    4. The sealed sachet containing the desiccant should be of appropriate size to forestall accidental chewing or swallowing.
    5. The sealed sachet containing the desiccant should carry bilingual warnings, e.g. "Do Not Eat" or 「不可食用」 .

    V. Melamine in Mainland's Milk Powder Incident

    In September 2008, cases of kidney stones affecting infants who had consumed melamine-tainted infant formula were reported in the Mainland. Such cases gave rise to grave public concern. The Mainland authority subsequently announced that a number of infant formulae made and sold in the Mainland were found to contain melamine, with the Sanlu brand having the highest level (up to 2 563 ppm), and that melamine at this level may affect the elimination of this chemical from the infant's body and result in kidney diseases, including the development of urinary stones.

    Even though Sanlu infant formula was not available in Hong Kong , follow-up actions undertaken by the Centre for Food Safety (CFS) found melamine in a number of milk and milk products available in Hong Kong . To safeguard public health and safety, CFS has been conducting food tests actively and announced the latest information through press releases and the CFS web site. A hotline has also been set up to answer public enquiries.

    What is Melamine?

    Melamine is an industrial chemical used for the production of melamine resins, which are used in glues, paper, textiles as well as plastics including tableware, kitchen utensils, etc. Apart from the potential adulteration of food, exposure to melamine for the general population has been considered to be low. Use of melamine as a food ingredient or a food additive is strictly forbidden in all countries. However, some people added melamine to foods in the manufacturing process to cause a false increase in the measurement of protein during protein tests by boosting their nitrogen levels.

    Health Effects of Melamine

    Melamine has low oral acute toxicity. However, excessive exposure to melamine has been found to cause urinary stones in experimental animals. Also, laboratory studies showed that melamine did not damage genetic materials in cells, and there was inadequate evidence to show that melamine can cause human cancers or malformation in foetus. However, intake of a significant amount of melamine can cause crystal formation in urinary tract. In severe cases, these crystals can form kidney stones, blocking the small tubes in the kidney, stopping the production of urine, causing kidney failure and death in some serious cases.

    Infants are particularly vulnerable and at risk of developing adverse health effects as a result of consuming melamine tainted milk-products because milk is their major food, and the amount of melamine intake per body weight is much higher than that of adults who consume a variety of foods. According to the epidemiological information obtained from the Mainland, over 99% of the victims were children aged 3 years or below. Affected children may experience symptoms of irritability of unknown reasons, blood in urine, little or no urine (in case of acute renal failure), stones in urine, high blood pressure, or pain over the kidney region.

    Safe Intake Level of Melamine

    Melamine can be present in the environment as a metabolite of the pesticide cyromazine. Traces of melamine may be present in food due to environmental contamination or through migration of melamine from food-handling utensils made of melamine. Therefore, the "zero tolerance" approach is not applicable to melamine.

    Under the amended Harmful Substances in Food Regulation (Cap. 132AF), milk, any food intended to be consumed principally by children under the age of 36 months and any food intended to be consumed principally by pregnant or lactating women shall not contain melamine exceeding 1 mg/kg. For other foods, the melamine level shall not exceed 2.5 mg/kg. The legal limit adopted in Hong Kong is based on risk assessment and is stringent enough to protect the health of both children and adults. With normal food intake, even if all the foods consumed each day by a person contain melamine, provided the melamine levels in all the foods comply with the legal limit, the foods would still be safe.

    Surveillance and Support Action of CFS

    Since September 2008, the CFS has been testing various infant formulae, milk, milk products and other food products (including fresh milk, ice-cream, ice-lolly, yogurt, baby food, nutritional supplements, instant drink mixes, biscuits, cakes, bread, chocolate and candies etc.) for melamine. The CFS has, on the recommendation of the Expert Group on Melamine Incident, expanded the food sampling plan to include food raw materials (e.g. eggs), meat and vegetables in the second phase of testing. Upon the conclusion of the second phase of testing on November 16, CFS has entered into the third phase since 17 November, in which samples of food types found unsatisfactory in the previous two phases have been retaken for testing.

    The latest results on the testing of food samples are available at the following web page:


    Advice to Trade

    1. Traders should not sell food products that have been found to contain melamine or use them as ingredients.
    2. Traders should ensure that their food products comply with the legal standards for melamine and are fit for human consumption.

    Readers' Corner

    Hazards of Seafood, Sushi and Sashimi - Vibrio Parahaemolyticus

    Hazards of Seafood, Sushi and Sashimi - Vibrio Parahaemolyticus

    Delicious foods from all over the world are available in Hong Kong , which is reputed as a fine dining hub. Seafood has always been a favourite of Hong Kong people. Sushi and sashimi, known for their freshness, have been very popular in recent years. These foods, however, pose hazards to our health despite their good taste. Seafood may contain Vibrio parahaemolyticus, and will easily cause food poisoning if not handled properly. Food handlers should pay extra attention in the preparation or supply of these foods.

    Vibrio parahaemolyticus as a cause of food poisoning

    Vibrio parahaemolyticus is a halophilic vibrio often found in the marine environment and seafood. This bacteria is highly reproductive. They can breed exponentially in room temperature of 18 °C to 22 °C in a few hours, and are one of the common causative agents of food poisoning. Consumption of seafood (in particular shellfish) that has not been thoroughly cooked may cause bacterial infection.

    One may develop symptoms including diarrhoea, vomiting, mild fever and abdominal pain, etc. usually within one to two days of being infected. They can recover after replenishing with water and electrolyte together with adequate rest. However, young children, the elderly or persons suffering from gastric diseases will easily get dehydrated upon infection. In this case, antibiotics treatment may be required.

    Vibrio parahaemolyticus can be destroyed by heating at or above 75 °C continuously for 30 seconds. Therefore, the best way to prevent food poisoning is to cook food thoroughly.

    Advice to trade:

    Advice to trade

    Acquire and provide fresh ingredients
    Keep clean
    Handle raw and cooked food separately
    Cook food thoroughly
    Keep food at safe temperature

    Food News

    Dietary fibre

    Dietary fibre

    his issue focuses on a food nutrient called dietary fibre, i.e., the item recommended for a "High" intake in the healthy eating campaign of "3 Low, 1 High" launched in recent years. Dietary fibre is mainly obtainable from vegetables, fruits, whole grain cereals and their products, and legumes, etc. Dietary fibre can be divided into soluble fibre and insoluble fibre. Although neither is absorbed directly by human body, both are indispensable to health. The questions and answers below can help you understand more about dietary fibre.

    Q1: Which one of the two dietary fibres is more important to human health?

    A1: Both of them are beneficial to our health in their own way. Insoluble fibre (mainly from whole grain cereals and vegetables) helps to stimulate intestinal movement, facilitates defecation and promotes intestinal health, whereas soluble fibre (mainly from fruits, beans and oatmeal) helps to lower blood cholesterol level and stabilise blood sugar level. Increased consumption of foods rich in dietary fibre may provide other health benefits such as weight management. In this way, we can kill many birds with one stone.

    Dietary fibre 2

    Q2: What is the adequate daily intake of dietary fibre?

    A2: The World Health Organisation recommends a daily intake of not less than 25g of dietary fibre for an average adult, and a daily consumption of 400g (about 10 taels) or above of vegetables and fruits for an individual to lower the risk of obesity and certain cardiovascular diseases. On top of taking enough dietary fibre, don't forget to drink enough water (about 6 to 8 glasses daily) as a complement!

    Q3: How can the daily intake of dietary fibre be increased?

    A3: We should choose cereals and cereal products with high dietary fibre content, for example, red rice / brown rice instead of white rice; whole wheat bread instead of white bread; oatmeal porridge instead of congee, etc. In addition, we should have two servings of fruit and three servings of vegetables each day. Do note that the content of dietary fibre in fruits and vegetables will be reduced if they are peeled or turned into juices.

    Dietary fibre 3

    Critical Control Point of Preparing Steamed Plain Chicken (For Trade)

    Poached chicken is a popular food on the menu of local Chinese restaurants. It is prepared by stewing a raw chicken in hot water. In fact, you need to pay attention to some critical points on safety during preparation of poached chicken. We have chosen steamed plain chicken, the most common type of poached chicken, to illustrate the critical control points that should be noted during preparation. By ensuring food safety, consumers can enjoy food safely.

    1 raw chicken…………….. 1.2 kg (about 2 catties)
    1. Rinse the chicken.
    2. Soak the whole chicken in boiling water. Then switch to low heat and stew the chicken for about 30 minutes.
    3. Cool the poached chicken and chop it for serving .

    Steps 1

    Steps 2

    Guidelines on Production of Steamed Plain Chicken

    1. Purchase and receipt
      • Purchase raw chicken from a reliable and hygienic supplier.
      • Inspect the storage conditions and temperature of the chicken upon receipt to ensure that the chicken is not contaminated.
    2. Storage
      • Store the chicken immediately at safe temperature
        • If the chicken is not for immediate preparation, it should be properly covered and stored in the refrigerator . It should be put under cooked food or ready-to-eat food to prevent cross-contamination . The best practice is to use two separate refrigerators for storing raw food and cooked food. The temperature inside the refrigerator should be checked and recorded regularly with a thermometer to ensure that the fridge remains at 4 C or below.
    3. Preparation
      • Before cooking / during preparation, wash hands thoroughly with warm water and liquid soap.
      • Before cooking , rinse the chicken.
    4. Cooking
      • The c hicken should be thoroughly cooked before consumption. When the steamed plain chicken is cut, its meat juice should be clear and not red, and blood is not visible.
      • Use a clean food thermometer to measure the core temperature of the thickest part of steamed plain chicken to ensure that it reaches at least 75 C. (CCP)
    5. Cooling
      • Cool the steamed plain chicken from 60 o C to 20 o C within 2 hours. (CCP)
      • Use potable water to cool the steamed plain chicken.
    6. Chopping
      • Before and after handling food, wash hands thoroughly with warm water and liquid soap.
      • Before and after handling food, rinse all food contact surfaces (including worktops, chopping boards , utensils, etc.) thoroughly.
      • Use two different sets of tools (including knives and chopping boards) for handling raw food and cooked food.
    7. Keeping and consumption
      • During display, the steamed plain chicken should be kept in a showcase that is insect- and dust-proof.
      • Record the time to indicate how long the steamed plain chicken has been stored at room temperature. Do not keep the steamed plain chicken at room temperature for more than 4 hours. (CCP)
      • If the steamed plain chicken has been held at room temperature for less than 2 hours, it should be refrigerated or used before the 4-hour limit is up.
      • If the steamed plain chicken has been held at room temperature for 2 to 4 hours, it should be consumed within the 4-hour limit but it should not be returned to the refrigerator.
      • If the steamed plain chicken has been held at room temperature for more than 4 hours, it should be discarded.
    8. Management System
      • A preventive food safety management system (such as the Hazard Analysis Critical Control Point ) should be implemented to identity and control any food safety problems that may emerge during production.

    Briefing of Activities

    I. Workshop on Nutrition Labelling Scheme

    To facilitate better understanding and compliance of the Nutrition Labelling Scheme, the Centre for Food Safety (CFS) has been conducting workshops for members of the food trade since this July. So far, workshops have been conducted for small and medium enterprises trading organic or health foods, food traders, laboratory service providers, food manufacturers, food importers/suppliers and food retailers. The recent one, targeting bakery operators, were held on October 16. For further details, please visit:


    Workshop on Nutrition Labelling Scheme 1

    Workshop on Nutrition Labelling Scheme 2

    The CFS has also prepared relevant Guidance Notes setting out details of the Scheme. The Guidance Notes, together with the enrolment form for the workshops, are available at:


    Copies of the Technical Guidance Notes on Nutrition Labelling and Nutrition Claims and Method Guidance Notes on Nutrition Labelling and Nutrition Claims can also be obtained from the Communication Resource Unit of CFS at 8/F Fa Yuen Street Municipal Services Building, 123A Fa Yuen Street , Mong Kok, Kowloon .

    II. Interviews with signatories of the Food Safety Charter

    With a view to setting a good example for the food trade to help build a food safe city, the Centre for Food Safety (CFS), in its publicity campaign to promote the "5 Keys to Food Safety" in mid-2008, invited food trade associations and licensed food premises to sign the Food Safety Charter. The response is encouraging with a total of 20 food trade associations and over 1 500 food premises having signed the Charter as at 1 st of November.

    Interviews with signatories of the Food Safety Charter 1

    Interviews with signatories of the Food Safety Charter 2

    One of the signatories, Mr CHE, said that apart from price and taste, the hygienic condition of food premises was also one of the major customers' concerns. Food hygiene and food safety, therefore, had been the focus of his Japanese restaurant well before he signed the Charter. Shortly after learning of this CFS campaign, Mr CHE enrolled to become one of the first signatories and encouraged active participation within his association. He found the 5 Keys to Food Safety – Handbook for Trade published by the CFS for this campaign very useful in educating his staff about food safety.

    Mr CHE was a "hands-on" person. He went to the market and made purchase by himself every two to three days. He emphasised that food ingredients must be purchased from reliable and reputable suppliers. He would educate his staff on proper food safety practices and arrange for them to receive training on the "5 Keys to Food Safety", so that they could be familiar with the food preparation steps and recognise the importance of food safety.

    He always reminded his staff to purchase fresh and wholesome food ingredients, check their quality upon receipt, reject dubious items, and, in the course of food preparation, ensure food safety to avoid problems arising from the food. He considered this a long term solution to reducing production cost in addition to minimising raw material wastage and product recall.

    As a catering operator for over 20 years, Mr CHE had been striving to provide quality customer-oriented services. He always encouraged his staff to apply the "5 Keys to Food Safety" in their daily work, so that customers would be impressed not only by the cuisine but also their sincerity in promoting food safety. As Mr CHE said, the financial tsunami had made customers more prudent in spending; food business operators had to be more conscious of food safety and quality in order to stand out in the industry.

    Another signatory, Mr WONG, considered that strict compliance with food safety rules was the key to customers' confidence, not only because Hong Kong was a world-class metropolis, but also because both local and overseas customers were expecting more from what they eat. As a professional catering operator who ran a renowned western restaurant, Mr WONG said that apart from enhancing the image of the restaurant, more importantly, signing the Charter helped to disseminate food safety messages to his staff and customers. His enthusiasm for promoting food safety was well-evidenced in the kitchen of his restaurant where the "5 Keys to Food Safety" posters could be seen all over the walls as a regular reminder to his staff. To Mr WONG, staff training was very important. He never missed the annual food hygiene seminar held by the Government and arranged for his staff to attend whenever possible in the hope that they could refresh their food safety knowledge and share new information with their colleagues.

    Mr WONG opined that the key to become a more reputable restaurant was enhanced environmental hygiene and food safety management. Customers naturally patronised more if they had confidence in a restaurant. He appealed to the trade to attach greater importance to food safety and join hands in keeping Hong Kong a food paradise.

    Information and details of the Food Safety Charter activities (including the invitation letter, application form and publicity material) are available at:


    The signatory list can be found in the following web site (for ease of reference, food premises are listed by name, district and type of cuisine):


    Legal Corner

    I. Regulations on Melamine

    In response to recent incidents of melamine found in dairy products of Hong Kong and the Mainland, the Government took contingency actions and amended the Harmful Substances in Food Regulations (Cap. 132AF), which has already come into operation, to safeguard public health.

    Under the Regulations, milk, any food intended to be consumed principally by children under the age of 36 months and any food intended to be consumed principally by pregnant or lactating women shall not contain melamine exceeding 1 mg/kg. For other food, the melamine level shall not exceed 2.5 mg/kg. "Milk" means cows milk, buffaloes milk and goats milk, and includes cream, separated milk and milk beverage, but does not include dried milk, condensed milk or reconstituted milk; "milk beverage" means any beverage resulting from combining liquid milk fat with other solids derived from milk, whether exclusive of any food additive or otherwise.

    According to the amended Regulations, any person who imports, consigns, delivers, manufactures or sells food with melamine concentration that exceeds the statutory limit commits an offence.

    II. The Public Health and Municipal Services (Amendment) Bill 2008

    There is an increasing number of food incidents happening all over the world and food safety is a concern of the general public. The food trade has the responsibility to ensure that the food they supply is safe and fit for human consumption. They also have the responsibility to stop supplying problem food to the market and recall problem food that has already been supplied to protect the health of consumers.

    In view of this, on October 24, the Government gazetted the Public Health and Municipal Services (Amendment) Bill 2008, which proposed to empower the Director of Food and Environmental Hygiene (DFEH) to make orders administratively to prohibit the import and supply of problem food, and direct that problem food supplied be recalled, to ensure food safety and protect public health. The Bill was submitted to the Legislative Council on November 5.

    Under the Public Health and Municipal Services (Amendment) Bill 2008, DFEH may make orders administratively if he has reasonable grounds to believe that the making of the order is necessary to prevent any danger to public health.

    DFEH will take into consideration the following factors in deciding whether to make the order:

    1. Information or document provided by the food traders, if any, on the safety of the food;
    2. results of food tests conducted by the Public Analyst, if available;
    3. results of food tests conducted by food safety authorities of other countries or places;
    4. food alerts issued by food safety authorities of other countries or places;
    5. time required for conducting the food test;
    6. the exposure of the general public and/or particular vulnerable groups to the food;
    7. consumption pattern relating to the food;
    8. statutory standard of the concerned substances in the food, if any;
    9. availability of information on the contamination of a particular batch or consignment of the food;
    10. availability of information on the contamination of a particular food factory or the whole region; and
    11. any other relevant considerations.

    Given that more than 90% of the food in Hong Kong is imported, a prohibition of import order is a highly effective and direct measure for stopping problem food from entering the Hong Kong market.

    For the latest information on the Public Health and Municipal Services (Amendment) Bill 2008, please visit http://www.fhb.gov.hk/.