In the classic article about the Penn. Dept of Agriculture, cecil says that Pennsalvania has the right to interefere with interstate commerce, and no one can stop them.
Doesn’t the Constition of the United States say that the U.S. Government have a clear rule that says the states DO NOT have the right to interefere with interstate commerce, only the US government has the right to do that.
You are correct that states are not allowed to put an undue burden on interestate commerce, or even to regulate it for that matter. For example, Penn. couldn’t keep out all baked goods from other states just to support the local baking industry: Dean Milk v. Madison (340 U.S. 349 (1951)) full text:
http://www.law.umkc.edu/faculty/projects/ftrials/conlaw/deanmilk.html
Also, I think there is a federal preemption issue with the FDA.
But, this is not my area of expertise, so I suspect that I am wrong for some reason or another. But, I would say you definitely pointed out Cecil’s dramatic overstatement.
BTW, Pennsylvania also regulates stuffed toys. There a “Reg. No. PA” on the tags of a lot of them.
Both of you are reading the column incorrectly. Here’s what Cecil actually says:
Pennsylvania does not have to right to “interfere with interstate commerce” but Cecil never says it does. It does have the right to regulate within the state.
Manufacturers outside the state have several choices: they can create special goods and packaging just for Pennsylvania; they can modify their goods and packaging so that they are acceptable in every state including Pennsylvania; or they can refrain from selling their goods in Pennsylvania altogether. This is the “burden” that Cecil mentions, but legally it is not at all the same thing as interference with Interstate commerce. Pennsylvania imposes no legal restrictions outside its state’s borders.
All states have some in-state requirements that are the equivalent of this, from California’s emissions regulations to the amount of deposit required on a returnable bottle.
Now, apologize to the Great Man. 
There’s also the fact that the rest of the states have decided to ride this on Pennsylvania’s dime.
It has always been my understanding that the Pennsylvania Code (for baked goods) is more stringent than the U.S. Code (and may be the most stringent in the nation), which is why companies seek out its stamp of approval. Goods not so stamped are not “inferior” as manufacturers are still required to meet USDA standards. I’m sure there are many products whose quality exceeds that necessary for PA approval, but there is no higher standard to refer to.
Of course, the state calls it regulation. It is not going to be called “Law to burden interstate commerce.” Cecil stopped short of a clear answer, thus no apology is necessary.
Actually, now that I think about it, there is probably a distinction when a state treats intrastate and interstate products equally. Since there is no exemption for goods made inside PA, it does not privledge in state goods over out of state goods, the way the Madison milk law did.
I can’t believe that there isn’t a member of the Teeming Millions who is a big Dormant Commerce Clause fan.