In recent years, there are increasing number of office workers using mini rice cookers or steam cookers, with the latter also carry reheating function, to cook rice or reheat food in office. These products are also getting popular among small households.
The Consumer Council tested and evaluated 6 mini rice cookers and 6 mini steam cookers based on safety (30%), performance (45%), durability on non-stick coating of mini rice cookers (10%) and ease of use (15%). 5 mini rice cookers and 2 mini steam cookers scored 4.5 out of 5. 3 mini steam cookers scored 4, and the remaining 1 mini rice cooker and 1 mini steam cooker scored 3.
In safety test, the measured temperature rise of test floor of 1 mini rice cooker sample was 70.5K, which slightly exceeded the maximum limit of 65K. Furthermore, its measured temperature rise of the internal wire was recorded as 81.4K, well above the maximum limit of 50K. Technically, the temperature rise limit is decided by the temperature rating of internal wire, but as the corresponding supplier failed to provide such information, the Council applied a more stringent limit under the standard of 50K in the test.
Besides, the measured power input of this mini rice cooker and another mini steam cooker sample was higher than the rated power input. Users of the products might under-estimate their actual power consumption and heating power, leading to electrical circuit overload. However, since the power consumption of these products is low, the risk is relatively low.
As for performance, a mini rice cooker took 16.3 to 20.3 minutes to cook 1 cup of white rice, versus a steam cooker which recommended 20 to 30 minutes to cook 180ml rice. Users of mini steam cookers have to set the steaming time manually due to product design. It was also worth noting that the internal thermostats of 2 samples were activated several times during the test due to overheating.
Reheating is another key feature of steam cookers. The samples tested took 17.6 to 25.7 minutes to reheat refrigerated rice to reach the temperature of 75°C in the centre.
Consumer should also pay attention to the rated "capacity" of the cooker. The rated capacity of the conventional rice cookers is usually the maximum amount of rice that can be cooked; but the rated capacity of most mini rice cookers and mini steam cookers is the maximum amount of water that the inner pot can be loaded.
Consumers should not make a purchase decision simply based on capacity, but should consider the recommended number of servings. The manufacturers should also clearly indicate whether the capacity refers to rice or water to make it easier for consumers to compare among different models.
The user manual of all mini steam cookers contains recommendation on the ratio of water and rice to be used. However, the recommended ratio of rice and water varies quite significantly among different models. Users should take trial and adjust the ratio according to their own preferences.
Furthermore, 7 samples were deficient in labelling mainly for missing warning statements and descriptions on product applicable environments and locations.
Consumers should beware of the following when using mini rice cooking products:
- Follow the instruction and do not exceed the maximum food capacity to avoid overload and spillovers;
- Before steaming, the plastic cover of the stainless steel inner pot must first be removed;
- Mini rice cooker has to be used with its original inner pot instead of other cooking containers. Do not heat the inner pot on the stove;
- Never wash or rinse a mini rice cooker and steam cooker as there are internal electric wiring. Remove stains from the edge or body of the cookers with a wet cloth, and wait until the appliances are completely dry before using.
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