Blender
A stand mixer or simply a mixer is an electrically operated kitchen appliance for mixing liquid or semi-solid ingredients or for pureeing food. In contrast to the blender sticks used for comparable purposes, these are floor-standing devices . The American term is blender , in German gastronomic blenders for mixing cocktails or in juice bars are so called.
The stand mixer was developed by Stephen Poplawski in 1922 . He used the machine to make mixed soda drinks. Fred Osius improved Poplawski's invention in 1935 when he developed the Waring Blendor from it .
A stand mixer consists of two main parts. The base contains an electric motor that can usually be switched or controlled for several operating speeds . A closed container made of stainless steel , glass or transparent plastic sits on top . At the bottom of the container there is a knife star that may be removable for cleaning purposes, depending on the design, which is set in rapid rotation by means of a coupling by the electric motor, in such a way crushing and mixing, emulsifying or suspending the ingredients .
The rotating knives fling the mixed goods against the wall of the container, creating an inefficient rotating funnel. An approximately triangular cross-section of the container and / or ribs on the wall help to break the rotating funnel and direct the flow of liquid back to the knives in the center. Some blenders require a lid to keep the liquid from splashing out of the container. Some models have additional cutting edges on the knife spider on the rear edge of the knife; By means of a switch position for the crushing of ice, the knife star is then rotated in the opposite direction, which counteracts premature wear of the actual knife edges.
The speed of rotation of the knife star has a major influence on the fineness of the solid particles that can be achieved or on the emulsion stability. A higher speed (e.g. 37,000 revolutions per minute in catering mixers compared to 12,000 revolutions per minute in household mixers) not only results in faster mixing results (mixing, smaller particle size as well as breaking down of plant fibers and cells). A shorter mixing process also means that the motor heats up less (overheating can lead to premature wear), which in addition to the more stable construction of these devices has a positive effect on the service life of the device. The noise emissions can, however, increase significantly at higher speeds.
Mixing for longer periods of time or higher rotation can cause the food to be heated up due to the effects of friction or cavitation and thus to better emulsification by melting the fats contained in it or to better dissolving sugar. In contrast, the warming can also have undesirable effects on vitamins and minerals that are not temperature- resistant .
More powerful mixers can start from standstill if the mixing container is already filled with ice, hard fruits or vegetables, otherwise larger ingredients may only be added during operation. The lids of many blender jugs have a central opening for this purpose, as liquid can be thrown out along the walls of the jar when the lid is completely removed.
For shredding hard objects (model cars, cell phones, batteries, etc.), shown in US commercials that have become famous through viral marketing (Will It Blend) , an extra robust special device with a stronger motor, more stable coupling and wear-resistant knives is required. An imitation in the blender at home would permanently damage the household appliance and could be dangerous for the user.
The frequently used polycarbonate mixing containers run the risk of releasing water-soluble, health- endangering plastic components such as bisphenol A when preparing hot pureed soup or during long periods of cleaning with hot water in the dishwasher .
Finer emulsions, nanosuspensions or extracts can only be achieved with special homogenizers , such as a dispersing stirring rod (see also Dispersion ), in which more efficient shear forces and cavitation effects arise in a narrow gap between a rotor and a stator .
See also
Individual evidence
- ↑ Results of volume measurements of popular blenders Smoothie-Mixer.de. Retrieved January 9, 2020.
- ^ Stiftung Warentest: Bisphenol A , Stiftung Warentest citing the Federal Environment Agency, accessed on October 1, 2011
- ↑ z. B. IKA-Ultra-Turrax