It said tests on 12 such blender models showed vast variances in both in blending and cooking performances, and they showed up in the smoothness, thickness, fineness and evenness of foods.

Two mini blenders from Bruno and Proluxury even failed to completely blend ingredients.

Generally speaking, mini blenders with a smaller capacity performed less satisfactorily.

Five models - Goldenwell, Primada, Proluxury, Cuisintec and Turbo Italy - posed potential hazards such as excessive temperature rises and insufficient insulation distance.

Mini blenders from the last two brands did not pass the temperature test, overheating when blending a lot of food and triggering their thermal protection mechanism, and the tests couldn't be completed.

One model recorded a temperature rise equivalent to 58 degrees Celcius at the power cord connector, exceeding the standard limit of 45 degrees.

Research and testing head Nora Tam Fung-yee said there is no need for a recall for now but warned people to stop using them if they sound strange.

The findings did not mean manufacturers had violated Trade Descriptions Ordinance.

"Since some models performed satisfactorily in cooking different dishes such as soymilk and black sesame soup, it depends on family size and cooking habits," said chief executive Gilly Wong Fung-han.