Food Safety Focus (58th Issue, May 2011) - Food Safety Platform

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Food Safety Focus (58th Issue, May 2011) - Food Safety Platform

Right Chemical for Right Food at Right Level -
A Key for the Use of Food Additive

Reported by Ms. Janny MA, Scientific Officer,
Risk Assessment Section, Centre for Food Safety

We all know that using non-permitted additives in food is not allowed as they may pose adverse effects to our health. However, for the permitted ones, which are determined to be safe under stringent evaluations conducted by international authorities, how can it still go wrong when they are used in food?

Right Chemicals on Wrong Food - Mislead Consumers

Most people choose food bearing alluring colours that appeal to their eyes. We are not likely to buy fish or meat with darkened or pale colour as they do not appear to be fresh. But what if the undesired colour is masked by some cunning tricks with the use of additives such as sulphur dioxide and colouring matters, we may be deceived.

No suphur dioxide is permitted in fresh meat
Sulphur dioxide is a multi-functional food additive of low toxicity. However. for susceptible individuals who are sensitive to it, allergy-like symptoms may be experienced. Sulphur dioxide is a permitted preservative and antioxidant in a wide range of food. It can also brighten the colour of raw meat e.g. beef and pork. The effect is particularly noticeable in meat that has been darkened over time after oxidation. Some dishonest traders take this advantage to sprinkle sulphur dioxide like magic powder to make the meat look fresher or even use it in frozen meat to disguise them as fresh meat which can then be sold at a higher market price.

Colouring matters are not allowed in fresh produce
Colour plays a distinguishing role in consumer perception of food. Colouring matters are often put into food to add or restore colour so as to make them more attractive and appetising. Permitted colouring matters determined to be safe can be used in a variety of food. However, some colouring matters may be exploited. For instance, to boost sales, ponceau 4R, a type of permitted colour, is misused in bigeye fish to make them look redder and fresher. Some dishonest traders may even dye other types of fish e.g. white croakers with tartrazine and sunset yellow FCF to imitate yellow croakers for higher profit!

Some dishonest vendors may dye white croakers (below) and sell them as yellow croakers (above) for higher profit
Some dishonest vendors may dye white croakers (below) and sell them as yellow croakers (above) for higher profit

Despite the safety of the permitted food additives upon normal consumption in the general population, the safety of consuming staled or even spoiled food treated by them is questionable. Legislation has been introduced to prevent potential health threats they may bring as well as protecting consumers from possible deception. Under local regulations, the uses of sulphur dioxide in fresh meat as well as colouring matters in raw and unprocessed meat, game, poultry, fish, fruit and vegetables are strictly not permitted.

Right Chemicals at Wrong Level - Excessive Use

Food additives play an important role in providing safe food supply as well as meeting consumers' needs. However, some unscrupulous manufacturers add excessive level of additives to disguise the properties of food e.g. make them look nicer, tastier and have longer shelf-life so as to generate higher revenue.

Excessive use of sulphur dioxide in dried abalone is not appropriate
Sulphur dioxide is one of the commonly used additives in dried fruits and pickled vegetables. However, the excessive uses of this additive have occasionally been detected in different foods, not limited to dried fruits and pickled vegetables but also dried abalone. In order to give expensive products like dried abalone longer shelf-lives and more pleasing lighter colours, some vendors use excessive levels of sulphur dioxide (some may even add several tens of times more than the legal limit) in dried abalone.

To safeguard public health, maximum permitted levels are set under specific local regulation for some additives, making reference to the Codex Standard. Not only the technological needs of using the additives have to be justified but the regulatory standards should also be complied with so as to ensure the intake of additives from all food uses does not exceed the safety reference values. Furthermore, the use of additives in accordance with Good Manufacturing Practice (GMP) i.e. only the minimum amount is added to achieve the desired technological effect should be followed.

Key for the Use of Additives

To protect food safety and consumers' right, the CFS is vigilant of improper uses of food additives. Food Surveillance Programme is in place to keep a close watch of the problem.

All in all, it is the responsibility of the trade to exercise due care in using food additives; right chemical for right food at right level is always the key to their appropriate use!