The six minute walk back to the car took 30+ minutes while she faffed about stopping, looking at things, dawdling, etc. (I'll not mention the riding off in the other direction thinking it was hilarious.) I asked her about 70 million times to hurry up, explained why we needed to get home, etc
Allow 30 minutes next time, then - toddlers need to dawdle and look at things. It's good for them. Or, if it is a real emergency, grab her and bike, and run - this means planning ahead and leaving two hands free, which not always easy with a baby (sling, rather than pram?). Or leave the bike behind until she understands not to ride off in the opposite direction.
OP - as other posters have said, just tell your toddler we don't put real juice into the doll's mouth, and remove it quietly - show her what to do instead. Shouting and getting cross will just encourage your dc to shout and get cross.
Supernanny is a lot of nonsense - the idea of toddlers being made to sit on steps and make pretend apologies afterwards is ridiculous. Makes good tv though.
For things like getting them dressed and out of the door quickly, I perfected a line in brisk/cheerful/incessant chat about what we were going to do later - no chance for them to interrupt, never mind object
.
Finally, calling a small child naughty is pointless - what do you think it achieves? Is it shaming her into good behaviour? Discipline isn't about shouting, anger and name-calling - it only works (in my experience) if you remain calm, quiet and firm.