The answer is no, as small induction brushless motors, such as single phase pumps, for example, are practically fixed speed devices. There are practically only two methods to change the rotation speed of AC induction motor: use frequency converter or use motor with sperate winding for different speeds.
Rgards,
IanP
DC brush motors used in AC applications, such as hand drills and small appliances, like your food processor, can be controlled with a triac. Take a look at the picture. This should work for 220VAC.
I do not know what the optocoupler is all about, but I hope this helps.