Microbiological Quality of Non-hot Served Sweet Food in Hong Kong
The Centre for Food Safety (CFS) and the Consumer Council (CC) have conducted a study on the microbiological quality of sweet food in Hong Kong. This study aimed to give an overview of the microbiological quality of some non-hot served sweet food commonly available at various local food premises and to increase awareness of safe preparation and handling of these products in the food industry.
2. In this study, a total of 114 non-hot served sweet food was collected from food premises, including chain and individual stores, located at different districts in Hong Kong. Various microbiological parameters, namely Salmonella species, Staphylococcus aureus and Bacillus cereus as well as aerobic colony count (ACC) and Escherichia coli (total) were tested by the Public Health Laboratory Services Branch of the Centre for Health Protection, Department of Health. The microbiological quality of the samples was assessed against the criteria stipulated in the Microbiological Guidelines for Ready-to-eat Food (The Guidelines) issued by the CFS.
3. The Guidelines stipulate criteria indicating the microbiological condition of the food concerned so as to reflect its safety and hygienic quality. According to the Guidelines, microbiological quality of food can be classified into one of the four classes*, namely Class A, Class B, Class C and Class D.
4. Among the 114 samples taken in this study, majority (93%) were of Class A or Class B quality. However, one Swiss roll sample was of Class D quality, which was potentially hazardous to the consumer, due to the excessive count of Staphylococcus aureus (5.0 × 105 cfu/g). In addition, 7 samples, including a coconut tart, a red bean sweet soup, a bean curd sheet sweet soup, a sesame sweet soup, two sweet sago cream with coconut milk and an osmanthus pudding, were of Class C quality due to excessive ACC, which indicated a need for improvement in hygienic conditions.
5. Post-cooking contamination, prolonged storage at room temperature and unhygienic handling might be the causes for the poor microbiological quality in samples as revealed in the study; highlighting the importance of good hygiene practices in the food industry. In order to help food trade implement food safety measures in their operations so as to produce and sell wholesome and safe sweet foods, the CFS has drafted a set of Trade Guidelines on Safe Production of Sweet Foods. After consulting with the trade, the Guidelines will be distributed and uploaded to the CFS website for trade reference.
Advice to the Public
- Patronise reliable and licensed food premises.
- Consume sweet foods as soon as possible.
- If cold served products are not consumed immediately, keep them in the fridge at or below 4℃.
Advice to Trade
- Purchase food ingredients from reliable sources.
- Estimate the demand of each type of sweet food carefully to avoid over-production.
- Plan the production schedule ahead to avoid preparing sweet foods too far in advance.
- Use separate utensils to handle raw food and cooked food or ready-to-eat food.
- Except food eaten raw, food should be cooked thoroughly, with core temperature reaching at least 75℃ for at least 30 seconds.
- Where appropriate, cool sweet food from 60℃ to 20℃ as quickly as possible (within 2 hours); and from 20℃ to 4℃, within 4 hours or less.
- If products are not served immediately, keep them in the fridge at or below 4℃.
- Always follow good personal hygiene practices.
6. The related article is published in the CHOICE MAGAZINE (Issue 413 released on 15 March 2011) (Chinese only).
Class A: the microbiological status of the food sample is satisfactory.
Class B: the microbiological status of the food sample is less than satisfactory but still acceptable for consumption.
Class C: the microbiological status of the food sample is unsatisfactory. Licensees of food premises should be advised to investigate and find out the causes and to adopt measures to improve the hygienic conditions.
Class D: the microbiological status of the food sample is unacceptable. The food sample contains unacceptable levels of specific pathogens that is potentially hazardous to the consumer. In addition to giving advice to the licensee of the food premises, warning letters as well as other enforcement actions should be considered.
Risk Assessment Section
Centre for Food Safety
Food and Environmental Hygiene Department