LCQ16: Bird's nests for sale in Hong Kong

     Following is a question by the Hon Fred Li Wah-ming and a written reply by the Secretary for Food and Health, Dr York Chow, in the Legislative Council today (October 19):


     In recent months, the mainland authorities have found that nitrite is present in various types of bird's nests available on the market; and sample tests on bird's nests available for sale in Hong Kong conducted recently by the Hong Kong University of Science and Technology reveal that all samples contained nitrite formed in natural environment.  Although the existing Preservatives in Food Regulation (Cap. 132BD) stipulates the maximum permitted levels of nitrite in a number of food categories (such as cured meat products, etc.), bird's nests and other food containing naturally formed nitrite are not subject to this Regulation.  In this connection, will the Government inform this Council:

(a) whether the authorities had conducted sample tests in the past three years on bird's nests available for sale in Hong Kong to ascertain if they contained nitrite or other preservatives; if the test results showed that the samples contained such substances, whether they had assessed if these substances were formed in the course of processing or in the natural environment; and

(b) whether it will amend the relevant Regulation to regulate the maximum permitted levels of nitrite in Chinese medicinal materials (such as bird's nests) or vegetables; if it will, of the details; if not, the reasons for that?



     Section 54 of the Public Health and Municipal Services Ordinance (Cap. 132) provides that all food that is offered for sale and intended for human consumption must be fit for this purpose.  The use and the levels of food additives in food shall also comply with the following Regulations:

(1) Colouring Matter in Food Regulations (Cap. 132H)
(2) Sweeteners in Food Regulations (Cap. 132U)
(3) Food and Drugs (Composition and Labelling) Regulations (Cap. 132W)
(4) Preservatives in Food Regulation (Cap. 132BD).

     According to the Preservatives in Food Regulation, nitrite and nitrate are only permitted to be used as preservatives in certain food categories such as cured meat and cheeses, but not bird's nests.  Nevertheless, section 3(10) of the same Regulation provides that it does not apply to an article of food containing any food additive that is naturally present in that food.  My reply to the different parts of the question is as follows:

(a) The findings of some studies (including those conducted by local universities) show that nitrite may exist naturally in bird's nests.  There is as yet no testing method to determine whether nitrite existing in bird's nests naturally occurs or is added intentionally.

     The Centre for Food Safety (CFS) of the Food and Environmental Hygiene Department conducts a risk-based routine food surveillance programme under which food samples are taken at import, wholesale and retail levels for chemical and microbiological testing to ensure that the food meets the requirements of local legislation and is fit for human consumption.  In the past 3 years, CFS took a total of 7 samples of bird's nests for chemical testing (including 6 for colouring matters and 1 for plasticisers).  The results of all such samples were satisfactory.

(b) At present, there is no international consensus on the regulatory standard of nitrite level in bird's nests and vegetables.  CFS will conduct risk assessment to determine whether the nitrite level in food will pose health risk to the public upon consumption.  Since nitrite is water-soluble, the process of washing and soaking will remove a substantial amount (up to more than 90%) of nitrite in bird's nests.  However, the water used for soaking bird's nests should be discarded since nitrite and nitrate have been dissolved into it.  The consumption of bird's nest stewed after thorough washing and soaking normally will not pose adverse health effect.

     Proper handling and cooking can effectively reduce the amount of nitrate and nitrite in vegetables.  For instance, vegetables not for immediate cooking should be kept refrigerated.  Before cooking, vegetables should be washed and peeled as appropriate.  Vegetables chopped or grated should be cooked as soon as possible.  Blanching is recommended for vegetables with high nitrate contents, but the water used should be discarded.

Ends/Wednesday, October 19, 2011
Issued at HKT 12:51