Not generally it could make them more aggro towards smaller tankmates however they shouldn't be housed with anything they would mistake for food anyway.
The other thing is unless you quarenteen the minnows for for about 4 weeks to make sure they are safe you shouldn't use them. Breeding and raising your own is another option. A good quality pellet should be the staple diet and then the feeders could be used as a weelky supplement/treat. Do not buy or catch feeders and throw them directly into the tank to be eaten.