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  • 2001.06.15

Test uncovers adulteration of foodstuff banned in China; consumers urged to opt for substitute

The Consumer Council has uncovered widespread adulteration of a popular Chinese hair-like foodstuff Nostoc which is banned in China for reasons of environmental protection.

The Council's test revealed that out of 30 Nostoc tested samples sourced from a wide diversity of retail outlets,and put to analysis for their authenticity, only 9 were found to be 100% Nostoc.

The remainders were adulterated to various degrees: 19 samples had 98% to 10% Nostoc; 2 were not detected of any Nostoc at all.

Nostoc is much favoured by local Chinese as an ingredient in dishes especially during the Chinese New Year because its name sounds like "fat choy" meaning prosperity in Cantonese.

Due to its sand bindin gproperties, Nostoc which is a wild blue-green alga grown on arid areas is essential to help prevent desertification. But the plant is in danger of fast disappearing because of the culinary demand for it.

Since last year, China has banned Nostoc gathering from the grasslands. Also forbidden is the processing, selling and export of the product. The ban apparently resulted in a shortage of the product giving rise to reports of fake Nostoc on sales in the market.

The test was conducted in co-operation with the Chinese University of Hong Kong to identify the authenticity of samples by (a) microscopic and (b) chemical methods. The samples were all sold at the time as Nostoc as claimed on the labelling or on the shelves, or assured by the retail outlets concerned.

Results of the test are most revealing. Besides widespread adulteration of the product, the test indicated that price bore little correlation to the authenticity of the samples.

While the cheapest sample priced at $18 per tael (per 37.8g) was not detected of any Nostoc, the most expensive sample at $58 per tael was detected of only 15% Nostoc.

Prior to authentication analysis: It is not easy to distinguish whether Nostoc is adulterated with non-Nostoc material ith the naked eye.

Authentication Method 1: Microscopic Analysis

Identification of Nostoc by High Power MicroscopeIdentification of Nostoc by High Power Microscope


Authentication Method 2: Simple and Easy Chemical Method to verify whether Nostoc has been adulterated with starch

1. Soak a small portion of Nostoc in a glass of water.Wait for 5 minutes.

Authentic Nostoc appears as green in colour.

Non-Nostoc portion turns into apparent dark blue or black colour. The colour change observed is due to the chemical reaction between starch in the non-Nostoc portion and iodine solution.

2. Place the soaked Nostoc on a transparent material against a light background. Add a few drops of Iodine solution until each strand of Nostoc is soaked with the solution.

The consumption of Nostoc is to be discouraged as it is detrimental to the environment, but equally objectionable is the practice of adulterating the product with non-Nostoc material without proper disclosure to the consumer.

Many of the retailers concerned have claimed ignorance of the authenticity of their products but the Council is of the view that they are nevertheless responsible for taking the necessary precautions to ensure that the products they sell are authentic. Alternatively,retailers should provide an accurate description of the product to the consumers.

Consumers, on the other hand, are urged to opt for a substitute in favour of Nostoc. Suppliers, traders and retailers should clearly declare any substitute in the Nostoc products - as in the case of vegetarian abalone or shark's fin imitate - for the information of consumers. And that any Nostoc substitute or imitate should not contain hazardous substance.

Lettuce has been suggested to consumers looking for a substitute as its name also carries a similar sound in Cantonese as "sang choy" meaning producing wealth. Not a bad choice -given lettuce is widely available and good for health.

To assist consumers, a simple do-it-yourself iodine test is suggested to identify products adulterated with non-Nostoc material composed of starch as found in this test (this method does not apply if the non-Nostoc material is not starch):

  • Soak the sample in a glass of water for 5 minutes.
  • Place a few strands of the sample on clear and translucent material.
  • Add a few drops of iodine solution to each strand for 2 to 3 minutes.
  • The Nostoc portion of the sample should remain green while the non-Nostoc starch portion will turn into dark blue or black.

Consumers will do well to consult the test report for more information on the findings in the latest (June) issue of CHOICE.

Council issues warning on potential hazards of disposable lighters

Caution is urged in the use of disposable lighters.

Out of 12 models tested by the Consumer Council, only 5 complied fully with the safety requirements of the Voluntary Standard BS EN ISO 9994:1996 on lighter specifications. The 7 other models were considered potentially hazardous to their users.

One of the hazards of these disposable lighters concerns the height of the flame they could produce. In one instance, when the test specimen was first struck by the user,the flame was found to reach a height of 150 mm (6 inches), which is 50 mm above the upper limit stipulated in such circumstance.

In another instance, when the specimen was deliberately adjusted to the manufacturer's design limit for maximum flame height, the flame shot up to as much as 220 mm(8.6 inches), in excess of the upper limit stipulated in such case by 70 mm.

In the test, 3 models were shown to fail to meet the safety requirements in respect of flame height.

So, always be wary of the flame height before you strike your lighter. Give plenty of safety allowance for the flame height especially when lighting a cigarette in the face.

In addition, 5models were found to exhibit a flame phenomenon known as spitting - due to escape of non-evaporated liquefied gas from the lighter producing a shower of burning liquid droplets separate from the main flame.

As a safety precaution, lighters should be able to automatically extinguish the flame in not more than 4 seconds once the user has released the gas button. 5 models were found to exceed this upper limit, and in the worst case, the flame lasted 55seconds before it extinguished!

Though disposabl elighters are cheap items priced from $1 to $4.9, consumers are advised to inspect the lighters when purchasing them. At least 2 of the specimens were found with visible cracks in the plastic gas compartment. This results in gas leakage posing risk of fire and explosion if near a source of ignition.

Besides safety concern, many models, including 3 of the models which passed the safety tests,were found to have defects of quality. Such defects which did not involve gas leakage, included the malfunctioning of rotary actuator after dropping, and melting of the plastic near the burner valve orifice after continuous burning for 2 minutes.

The Consumer Council has drawn the attention of the government - Economic Services Bureau,Electrical and Mechanical Services Department, and Customs and Excise Department- to the findings of the tests.

The Council noted that almost all of the models (11 out of 12) have on their products bilingual warning labels, a safety measure which the Council recommended some 3 years ago.

Between January2000 and May this year, a total of 11 cases of accidents related to the misuse or mishandling of lighters were reported resulting in 1 dead and 9 injured.However, a consumer who was injured by a defective product may seek civil remedy through the court.

MPF consumers lose out on interest income

The Consumer Council has expressed concerns over the issue of funds-in-transit in Mandatory Provident Fund (MPF) schemes. The transition occurs when funds are pending investment, during fund switching or upon withdrawal of benefits.

This followed the latest Council survey of MPF service providers published today in CHOICE. A similar survey was also conducted a year ago before the introduction of MPF in December 2000.

First and foremost,the survey has revealed differences in the practice of MPF service providers in respect of funds-in-transit. Many MPF service providers were found to leave such funds-in-transit in non-interest-bearing accounts.

About 30% (fund switching) to more than half (withdrawal of benefits) of the schemes surveyed followed this practice. In consequence, consumers are losing out on interest income which could otherwise be gainfully employed to enlarge the pool of assets in investment funds and/or to offset expenses.

Depending on the operation process and the dealing frequency of the constituent funds in a cheme, the transition period normally takes one or two weeks, according to the survey.

The longer the period and the larger the amount of the funds-in-transit, the more interest the MPF members will stand to lose.

Second, the survey also raised the issue of the lack of clear and proper legislative control over the handling of funds-in-transit in MPF schemes. To safeguard the interest of consumers, the Council has put forward these proposals:

  • All funds-in-transit should be deposited in only interest-bearing accounts, and its transparency of operation enhanced for information of consumers.
  • The regulatory procedures for funds-in-transit should be strengthened to ensure their integrity and security.
  • The operation of funds-in-transit should be streamlined to keep the transition period to the minimum.

Third, the survey noted an overall reduction in the fees and charges of MPF service providers over the past year. However, while some schemes have reduced their current fees,other schemes which previously waived fees and charges, have reinstated them,according to the survey.

Already the survey has found that some schemes have raised the maximum fee level thus allowing MP Fservice providers to increase the current fees to the maximum level after giving a 3-month notice in advance.

For schemes wit hwaived fees and charges, consumers should pay heed to any conditions imposed,for instance, if the service providers are allowed to unilaterally raise the fees in future or if the exemption period is for only 1 or 2 years.

In addition, the survey also noted the consolidation of some MPF service providers. The Council is concerned that should this trend of consolidation in the MPF industry continue, it may have an adverse effect on market competition resulting in higher fees by MPF service providers.

Timely and comprehensive test findings to assist consumes shopping for air-conditioners

Imagine the long hot summer without air-conditioners. Help is on hand for the consumers shopping for window-type air-conditioners to beat the heat and humidity of summer.

The Consumer Council has tested 15 models of claimed cooling capacity between 2 to 2.14 kW -suitable for cooling a small bedroom.

By and large, the air-conditioners were able to deliver the cooling capacity they claimed. Though11 samples were found to be less than the claimed capacity, the discrepancies were within 5% - a definite improvement over past test results when differences of up to 15% or more were detected.

All samples in the test carried the energy labels of the government voluntary Energy Efficiency Labelling Scheme (EELS). When the test figures were converted into the Energy Consumption Indices, the values of 4 samples were found to exceed the upper limit of Grade 1 (the lower the index the better).

In the report was estimated the annual running cost of electricity of each model - varying from$811 to $964, a difference of 16% or a saving of $153 a year.

On the problem of dripping of condensate water, with the exception of one all models were found to pass the dripping test. However, under the extremely humid ambient condition in summer here, most air-conditioners may still produce dripping on the outside as the large amount of condensate water may not evaporate fast enough Consumers are, therefore, advised to install a drain hose if dripping does occur.

Air-conditioners in operation invariably generate noise. The test found a range of nearly 10dBbetween the quietest and the noisiest samples (when tested in a reflective environment at the lowest fan speed) - not an unnoticeable difference especially to the noise sensitive in their sleep.

Increasingly air-conditioner manufacturers compete on the quietness of their products with claims of low noise level. 4 models with claimed noise level of below 40 dB were put to the test and the results revealed discrepancies between the measured values and the manufacturer's claims of 3.3 to 4.5 dB.

Significant variations found in length, unit price and quality of toilet rolls

In choosing a toilet roll, does low price necessarily represent good value for money? Or, is there more to it (beneath the marked price and packaging) than meets the eye?

Sure enough a Consumer Council test report on 15 models of toilet rolls for household use,priced from $9.9 to $38.5 per 10-roll package, has shown toilet rolls to vary substantially in length, unit price and, to some extent, in quality too.

On the average total length per roll of the models, the test found them to vary in length from15.7 m to more than double to 38.9 m - a difference of 23.2 m!

But a toilet roll with more length is not necessarily more economical. It has to take into account the price in relation to the quantity.

Again considerable difference existed in the unit price per 100 sheets (from 50 cents to $1.6) and the unit price per 10 m ² (from $4.2 to $11.8). In both cases the difference is almost treble!

The test, however,could not establish a direct correlation between price and quality, such characteristics as tensile strength, softness, water absorption, speed of disintegration, ease of tear, cleanliness, etc., which were rated in the report.

Quality is often a matter of personal preference and varies in importance from consumer to consumer.

On the whole, the quality of toilet rolls at the lower end of the price scale fared reasonably well in comparison to the more expensive models, except for softness and cleanliness in terms of bacterial count (but poses no health risk).

An additional test was conducted on 4 models of jumbo toilet rolls for use of institutions /organisations, priced from $168 to $270 per 12-roll carton.